Davidlohr Bueso [Wed, 13 Sep 2017 20:08:21 +0000 (13:08 -0700)]
kvm,x86: Fix apf_task_wake_one() wq serialization
During code inspection, the following potential race was seen:
CPU0 CPU1
kvm_async_pf_task_wait apf_task_wake_one
[L] swait_active(&n->wq)
[S] prepare_to_swait(&n.wq)
[L] if (!hlist_unhahed(&n.link))
schedule() [S] hlist_del_init(&n->link);
Properly serialize swait_active() checks such that a wakeup is
not missed.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Davidlohr Bueso [Wed, 13 Sep 2017 20:08:20 +0000 (13:08 -0700)]
kvm,lapic: Justify use of swait_active()
A comment might serve future readers.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Davidlohr Bueso [Wed, 13 Sep 2017 20:08:19 +0000 (13:08 -0700)]
kvm,async_pf: Use swq_has_sleeper()
... as we've got the new helper now. This caller already
does the right thing, hence no changes in semantics.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Davidlohr Bueso [Wed, 13 Sep 2017 20:08:18 +0000 (13:08 -0700)]
sched/wait: Add swq_has_sleeper()
Which is the equivalent of what we have in regular waitqueues.
I'm not crazy about the name, but this also helps us get both
apis closer -- which iirc comes originally from the -net folks.
We also duplicate the comments for the lockless swait_active(),
from wait.h. Future users will make use of this interface.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Jan H. Schönherr [Thu, 7 Sep 2017 18:02:30 +0000 (19:02 +0100)]
KVM: VMX: Do not BUG() on out-of-bounds guest IRQ
The value of the guest_irq argument to vmx_update_pi_irte() is
ultimately coming from a KVM_IRQFD API call. Do not BUG() in
vmx_update_pi_irte() if the value is out-of bounds. (Especially,
since KVM as a whole seems to hang after that.)
Instead, print a message only once if we find that we don't have a
route for a certain IRQ (which can be out-of-bounds or within the
array).
This fixes CVE-2017-1000252.
Fixes:
efc644048ecde54 ("KVM: x86: Update IRTE for posted-interrupts")
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Jan H. Schönherr [Thu, 7 Sep 2017 18:02:48 +0000 (19:02 +0100)]
KVM: Don't accept obviously wrong gsi values via KVM_IRQFD
We cannot add routes for gsi values >= KVM_MAX_IRQ_ROUTES -- see
kvm_set_irq_routing(). Hence, there is no sense in accepting them
via KVM_IRQFD. Prevent them from entering the system in the first
place.
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Jim Mattson [Tue, 12 Sep 2017 20:02:54 +0000 (13:02 -0700)]
kvm: nVMX: Don't allow L2 to access the hardware CR8
If L1 does not specify the "use TPR shadow" VM-execution control in
vmcs12, then L0 must specify the "CR8-load exiting" and "CR8-store
exiting" VM-execution controls in vmcs02. Failure to do so will give
the L2 VM unrestricted read/write access to the hardware CR8.
This fixes CVE-2017-12154.
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Ladi Prosek [Thu, 14 Sep 2017 09:50:07 +0000 (11:50 +0200)]
KVM: trace events: update list of exit reasons
Adding entries for exit reasons 23 - 27:
KVM_EXIT_EPR
KVM_EXIT_SYSTEM_EVENT
KVM_EXIT_S390_STSI
KVM_EXIT_IOAPIC_EOI
KVM_EXIT_HYPERV
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Wanpeng Li [Thu, 14 Sep 2017 10:54:16 +0000 (03:54 -0700)]
KVM: async_pf: Fix #DF due to inject "Page not Present" and "Page Ready" exceptions simultaneously
qemu-system-x86-8600 [004] d..1 7205.687530: kvm_entry: vcpu 2
qemu-system-x86-8600 [004] .... 7205.687532: kvm_exit: reason EXCEPTION_NMI rip 0xffffffffa921297d info
ffffeb2c0e44e018 80000b0e
qemu-system-x86-8600 [004] .... 7205.687532: kvm_page_fault: address
ffffeb2c0e44e018 error_code 0
qemu-system-x86-8600 [004] .... 7205.687620: kvm_try_async_get_page: gva = 0xffffeb2c0e44e018, gfn = 0x427e4e
qemu-system-x86-8600 [004] .N.. 7205.687628: kvm_async_pf_not_present: token 0x8b002 gva 0xffffeb2c0e44e018
kworker/4:2-7814 [004] .... 7205.687655: kvm_async_pf_completed: gva 0xffffeb2c0e44e018 address 0x7fcc30c4e000
qemu-system-x86-8600 [004] .... 7205.687703: kvm_async_pf_ready: token 0x8b002 gva 0xffffeb2c0e44e018
qemu-system-x86-8600 [004] d..1 7205.687711: kvm_entry: vcpu 2
After running some memory intensive workload in guest, I catch the kworker
which completes the GUP too quickly, and queues an "Page Ready" #PF exception
after the "Page not Present" exception before the next vmentry as the above
trace which will result in #DF injected to guest.
This patch fixes it by clearing the queue for "Page not Present" if "Page Ready"
occurs before the next vmentry since the GUP has already got the required page
and shadow page table has already been fixed by "Page Ready" handler.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Fixes:
7c90705bf2a3 ("KVM: Inject asynchronous page fault into a PV guest if page is swapped out.")
[Changed indentation and added clearing of injected. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Radim Krčmář [Thu, 14 Sep 2017 15:21:10 +0000 (17:21 +0200)]
Merge branch 'kvm-ppc-fixes' of git://git./linux/kernel/git/paulus/powerpc
Bug fixes for stable.
Wanpeng Li [Wed, 13 Sep 2017 11:04:01 +0000 (04:04 -0700)]
KVM: X86: Don't block vCPU if there is pending exception
Don't block vCPU if there is pending exception.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Suravee Suthikulpanit [Tue, 12 Sep 2017 15:42:42 +0000 (10:42 -0500)]
KVM: SVM: Add irqchip_split() checks before enabling AVIC
SVM AVIC hardware accelerates guest write to APIC_EOI register
(for edge-trigger interrupt), which means it does not trap to KVM.
So, only enable SVM AVIC only in split irqchip mode.
(e.g. launching qemu w/ option '-machine kernel_irqchip=split').
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Fixes:
44a95dae1d22 ("KVM: x86: Detect and Initialize AVIC support")
[Removed pr_debug - Radim.]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Suravee Suthikulpanit [Tue, 12 Sep 2017 15:42:41 +0000 (10:42 -0500)]
KVM: Add struct kvm_vcpu pointer parameter to get_enable_apicv()
Modify struct kvm_x86_ops.arch.apicv_active() to take struct kvm_vcpu
pointer as parameter in preparation to subsequent changes.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Suravee Suthikulpanit [Tue, 12 Sep 2017 15:42:40 +0000 (10:42 -0500)]
KVM: SVM: Refactor AVIC vcpu initialization into avic_init_vcpu()
Preparing the base code for subsequent changes. This does not change
existing logic.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Radim Krčmář [Wed, 13 Sep 2017 13:13:46 +0000 (15:13 +0200)]
KVM: x86: fix clang build
Clang resolves __builtin_constant_p() to false even if the expression is
constant in the end. The only purpose of that expression was to
differentiate a case where the following expression couldn't be checked
at compile-time, so we can just remove the check.
Clang handles the following two correctly. Turn it into BUG_ON if there
are any more problems with this.
Fixes:
d6321d493319 ("KVM: x86: generalize guest_cpuid_has_ helpers")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Christian Borntraeger [Wed, 13 Sep 2017 12:17:22 +0000 (14:17 +0200)]
KVM: fix rcu warning on VM_CREATE errors
commit
3898da947bba ("KVM: avoid using rcu_dereference_protected") can
trigger the following lockdep/rcu splat if the VM_CREATE ioctl fails,
for example if kvm_arch_init_vm fails:
WARNING: suspicious RCU usage
4.13.0+ #105 Not tainted
-----------------------------
./include/linux/kvm_host.h:481 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
no locks held by qemu-system-s39/79.
stack backtrace:
CPU: 0 PID: 79 Comm: qemu-system-s39 Not tainted 4.13.0+ #105
Hardware name: IBM 2964 NC9 704 (KVM/Linux)
Call Trace:
([<
00000000001140b2>] show_stack+0xea/0xf0)
[<
00000000008a68a4>] dump_stack+0x94/0xd8
[<
0000000000134c12>] kvm_dev_ioctl+0x372/0x7a0
[<
000000000038f940>] do_vfs_ioctl+0xa8/0x6c8
[<
0000000000390004>] SyS_ioctl+0xa4/0xb8
[<
00000000008c7a8c>] system_call+0xc4/0x27c
no locks held by qemu-system-s39/79.
We have to reset the just created users_count back to 0 to
tell the check to not trigger.
Reported-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Fixes:
3898da947bba ("KVM: avoid using rcu_dereference_protected")
Cc: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Jan H. Schönherr [Wed, 6 Sep 2017 16:34:06 +0000 (18:34 +0200)]
KVM: x86: Fix immediate_exit handling for uninitialized AP
When user space sets kvm_run->immediate_exit, KVM is supposed to
return quickly. However, when a vCPU is in KVM_MP_STATE_UNINITIALIZED,
the value is not considered and the vCPU blocks.
Fix that oversight.
Fixes:
460df4c1fc7c008 ("KVM: race-free exit from KVM_RUN without POSIX signals")
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Jan H. Schönherr [Tue, 5 Sep 2017 22:27:19 +0000 (00:27 +0200)]
KVM: x86: Fix handling of pending signal on uninitialized AP
KVM API says that KVM_RUN will return with -EINTR when a signal is
pending. However, if a vCPU is in KVM_MP_STATE_UNINITIALIZED, then
the return value is unconditionally -EAGAIN.
Copy over some code from vcpu_run(), so that the case of a pending
signal results in the expected return value.
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Jan H. Schönherr [Tue, 5 Sep 2017 21:58:44 +0000 (23:58 +0200)]
KVM: SVM: Add a missing 'break' statement
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Fixes:
f6511935f424 ("KVM: SVM: Add checks for IO instructions")
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Joerg Roedel [Mon, 28 Aug 2017 14:38:35 +0000 (16:38 +0200)]
KVM: x86: Remove .get_pkru() from kvm_x86_ops
The commit
9dd21e104bc ('KVM: x86: simplify handling of PKRU')
removed all users and providers of that call-back, but
didn't remove it. Remove it now.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Paul Mackerras [Tue, 12 Sep 2017 03:47:23 +0000 (13:47 +1000)]
KVM: PPC: Book3S HV: Fix bug causing host SLB to be restored incorrectly
Aneesh Kumar reported seeing host crashes when running recent kernels
on POWER8. The symptom was an oops like this:
Unable to handle kernel paging request for data at address 0xf00000000786c620
Faulting instruction address: 0xc00000000030e1e4
Oops: Kernel access of bad area, sig: 11 [#1]
LE SMP NR_CPUS=2048 NUMA PowerNV
Modules linked in: powernv_op_panel
CPU: 24 PID: 6663 Comm: qemu-system-ppc Tainted: G W 4.13.0-rc7-43932-gfc36c59 #2
task:
c000000fdeadfe80 task.stack:
c000000fdeb68000
NIP:
c00000000030e1e4 LR:
c00000000030de6c CTR:
c000000000103620
REGS:
c000000fdeb6b450 TRAP: 0300 Tainted: G W (4.13.0-rc7-43932-gfc36c59)
MSR:
9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR:
24044428 XER:
20000000
CFAR:
c00000000030e134 DAR:
f00000000786c620 DSISR:
40000000 SOFTE: 0
GPR00:
0000000000000000 c000000fdeb6b6d0 c0000000010bd000 000000000000e1b0
GPR04:
c00000000115e168 c000001fffa6e4b0 c00000000115d000 c000001e1b180386
GPR08:
f000000000000000 c000000f9a8913e0 f00000000786c600 00007fff587d0000
GPR12:
c000000fdeb68000 c00000000fb0f000 0000000000000001 00007fff587cffff
GPR16:
0000000000000000 c000000000000000 00000000003fffff c000000fdebfe1f8
GPR20:
0000000000000004 c000000fdeb6b8a8 0000000000000001 0008000000000040
GPR24:
07000000000000c0 00007fff587cffff c000000fdec20bf8 00007fff587d0000
GPR28:
c000000fdeca9ac0 00007fff587d0000 00007fff587c0000 00007fff587d0000
NIP [
c00000000030e1e4] __get_user_pages_fast+0x434/0x1070
LR [
c00000000030de6c] __get_user_pages_fast+0xbc/0x1070
Call Trace:
[
c000000fdeb6b6d0] [
c00000000139dab8] lock_classes+0x0/0x35fe50 (unreliable)
[
c000000fdeb6b7e0] [
c00000000030ef38] get_user_pages_fast+0xf8/0x120
[
c000000fdeb6b830] [
c000000000112318] kvmppc_book3s_hv_page_fault+0x308/0xf30
[
c000000fdeb6b960] [
c00000000010e10c] kvmppc_vcpu_run_hv+0xfdc/0x1f00
[
c000000fdeb6bb20] [
c0000000000e915c] kvmppc_vcpu_run+0x2c/0x40
[
c000000fdeb6bb40] [
c0000000000e5650] kvm_arch_vcpu_ioctl_run+0x110/0x300
[
c000000fdeb6bbe0] [
c0000000000d6468] kvm_vcpu_ioctl+0x528/0x900
[
c000000fdeb6bd40] [
c0000000003bc04c] do_vfs_ioctl+0xcc/0x950
[
c000000fdeb6bde0] [
c0000000003bc930] SyS_ioctl+0x60/0x100
[
c000000fdeb6be30] [
c00000000000b96c] system_call+0x58/0x6c
Instruction dump:
7ca81a14 2fa50000 41de0010 7cc8182a 68c60002 78c6ffe2 0b060000 3cc2000a
794a3664 390610d8 e9080000 7d485214 <
e90a0020>
7d435378 790507e1 408202f0
---[ end trace
fad4a342d0414aa2 ]---
It turns out that what has happened is that the SLB entry for the
vmmemap region hasn't been reloaded on exit from a guest, and it has
the wrong page size. Then, when the host next accesses the vmemmap
region, it gets a page fault.
Commit
a25bd72badfa ("powerpc/mm/radix: Workaround prefetch issue with
KVM", 2017-07-24) modified the guest exit code so that it now only clears
out the SLB for hash guest. The code tests the radix flag and puts the
result in a non-volatile CR field, CR2, and later branches based on CR2.
Unfortunately, the kvmppc_save_tm function, which gets called between
those two points, modifies all the user-visible registers in the case
where the guest was in transactional or suspended state, except for a
few which it restores (namely r1, r2, r9 and r13). Thus the hash/radix indication in CR2 gets corrupted.
This fixes the problem by re-doing the comparison just before the
result is needed. For good measure, this also adds comments next to
the call sites of kvmppc_save_tm and kvmppc_restore_tm pointing out
that non-volatile register state will be lost.
Cc: stable@vger.kernel.org # v4.13
Fixes:
a25bd72badfa ("powerpc/mm/radix: Workaround prefetch issue with KVM")
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Paul Mackerras [Mon, 11 Sep 2017 06:05:30 +0000 (16:05 +1000)]
KVM: PPC: Book3S HV: Hold kvm->lock around call to kvmppc_update_lpcr
Commit
468808bd35c4 ("KVM: PPC: Book3S HV: Set process table for HPT
guests on POWER9", 2017-01-30) added a call to kvmppc_update_lpcr()
which doesn't hold the kvm->lock mutex around the call, as required.
This adds the lock/unlock pair, and for good measure, includes
the kvmppc_setup_partition_table() call in the locked region, since
it is altering global state of the VM.
This error appears not to have any fatal consequences for the host;
the consequences would be that the VCPUs could end up running with
different LPCR values, or an update to the LPCR value by userspace
using the one_reg interface could get overwritten, or the update
done by kvmhv_configure_mmu() could get overwritten.
Cc: stable@vger.kernel.org # v4.10+
Fixes:
468808bd35c4 ("KVM: PPC: Book3S HV: Set process table for HPT guests on POWER9")
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Benjamin Herrenschmidt [Wed, 6 Sep 2017 05:20:55 +0000 (15:20 +1000)]
KVM: PPC: Book3S HV: Don't access XIVE PIPR register using byte accesses
The XIVE interrupt controller on POWER9 machines doesn't support byte
accesses to any register in the thread management area other than the
CPPR (current processor priority register). In particular, when
reading the PIPR (pending interrupt priority register), we need to
do a 32-bit or 64-bit load.
Cc: stable@vger.kernel.org # v4.13
Fixes:
2c4fb78f78b6 ("KVM: PPC: Book3S HV: Workaround POWER9 DD1.0 bug causing IPB bit loss")
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Linus Torvalds [Fri, 8 Sep 2017 22:18:36 +0000 (15:18 -0700)]
Merge tag 'kvm-4.14-1' of git://git./virt/kvm/kvm
Pull KVM updates from Radim Krčmář:
"First batch of KVM changes for 4.14
Common:
- improve heuristic for boosting preempted spinlocks by ignoring
VCPUs in user mode
ARM:
- fix for decoding external abort types from guests
- added support for migrating the active priority of interrupts when
running a GICv2 guest on a GICv3 host
- minor cleanup
PPC:
- expose storage keys to userspace
- merge kvm-ppc-fixes with a fix that missed 4.13 because of
vacations
- fixes
s390:
- merge of kvm/master to avoid conflicts with additional sthyi fixes
- wire up the no-dat enhancements in KVM
- multiple epoch facility (z14 feature)
- Configuration z/Architecture Mode
- more sthyi fixes
- gdb server range checking fix
- small code cleanups
x86:
- emulate Hyper-V TSC frequency MSRs
- add nested INVPCID
- emulate EPTP switching VMFUNC
- support Virtual GIF
- support 5 level page tables
- speedup nested VM exits by packing byte operations
- speedup MMIO by using hardware provided physical address
- a lot of fixes and cleanups, especially nested"
* tag 'kvm-4.14-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (67 commits)
KVM: arm/arm64: Support uaccess of GICC_APRn
KVM: arm/arm64: Extract GICv3 max APRn index calculation
KVM: arm/arm64: vITS: Drop its_ite->lpi field
KVM: arm/arm64: vgic: constify seq_operations and file_operations
KVM: arm/arm64: Fix guest external abort matching
KVM: PPC: Book3S HV: Fix memory leak in kvm_vm_ioctl_get_htab_fd
KVM: s390: vsie: cleanup mcck reinjection
KVM: s390: use WARN_ON_ONCE only for checking
KVM: s390: guestdbg: fix range check
KVM: PPC: Book3S HV: Report storage key support to userspace
KVM: PPC: Book3S HV: Fix case where HDEC is treated as 32-bit on POWER9
KVM: PPC: Book3S HV: Fix invalid use of register expression
KVM: PPC: Book3S HV: Fix H_REGISTER_VPA VPA size validation
KVM: PPC: Book3S HV: Fix setting of storage key in H_ENTER
KVM: PPC: e500mc: Fix a NULL dereference
KVM: PPC: e500: Fix some NULL dereferences on error
KVM: PPC: Book3S HV: Protect updates to spapr_tce_tables list
KVM: s390: we are always in czam mode
KVM: s390: expose no-DAT to guest and migration support
KVM: s390: sthyi: remove invalid guest write access
...
Linus Torvalds [Fri, 8 Sep 2017 22:11:20 +0000 (15:11 -0700)]
Merge tag 'linux-kselftest-4.14-rc1-update' of git://git./linux/kernel/git/shuah/linux-kselftest
Pull kselftest updates from Shuah Khan:
- TAP13 framework API and converting tests to TAP13 continues. A few
more tests are converted and kselftest common RUN_TESTS in lib.mk is
enhanced to print TAP13 to cover test shell scripts that won't be
able to use kselftest API.
- Several fixes to existing tests to not fail in unsupported cases.
This has been an ongoing work based on the feedback from stable
release kselftest users.
- A new watchdog test and much needed cleanups to the existing tests
from Eugeniu Rosca.
- Changes to kselftest common lib.mk framework to make RUN_TESTS a
function to be called from individual test make files to run stress
and destructive sub-tests.
* tag 'linux-kselftest-4.14-rc1-update' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (41 commits)
selftests: Enhance kselftest_harness.h to print which assert failed
selftests: lib.mk: change RUN_TESTS to print messages in TAP13 format
selftests: change lib.mk RUN_TESTS to take test list as an argument
selftests: lib.mk: suppress "cd" output from run_tests target
selftests: kselftest framework: change skip exit code to 0
selftests/timers: make loop consistent with array size
selftests: timers: remove rtctest_setdate from run_destructive_tests
selftests: timers: Fix run_destructive_tests target to handle skipped tests
kselftests: timers: leap-a-day: Change default arguments to help test runs
selftests: timers: drop support for !KTEST case
rtc: rtctest: Improve support detection
selftests/cpu-hotplug: Skip test when there is only one online cpu
selftests/cpu-hotplug: exit with failure when test occured unexpected behaviors
selftests: futex: convert test to use ksft TAP13 framework
selftests: capabilities: convert error output to TAP13 ksft framework
selftests: memfd: Align STACK_SIZE for ARM AArch64 system
selftests: warn if failure is due to lack of executable bit
selftests: kselftest framework: add error counter
selftests: capabilities: convert the test to use TAP13 ksft framework
selftests: capabilities: fix to run Non-root +ia, sgidroot => i test
...
Linus Torvalds [Fri, 8 Sep 2017 22:08:14 +0000 (15:08 -0700)]
Merge tag 'trace-v4.14' of git://git./linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"Nothing new in development for this release. These are mostly fixes
that were found during development of changes for the next merge
window and fixes that were sent to me late in the last cycle"
* tag 'trace-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Apply trace_clock changes to instance max buffer
tracing: Fix clear of RECORDED_TGID flag when disabling trace event
tracing: Add barrier to trace_printk() buffer nesting modification
ftrace: Fix memleak when unregistering dynamic ops when tracing disabled
ftrace: Fix selftest goto location on error
ftrace: Zero out ftrace hashes when a module is removed
tracing: Only have rmmod clear buffers that its events were active in
ftrace: Fix debug preempt config name in stack_tracer_{en,dis}able
Linus Torvalds [Fri, 8 Sep 2017 21:32:34 +0000 (14:32 -0700)]
genksyms: fix gperf removal conversion
I had stupidly missed one special use of 'is_reserved_word()' when I
converted the code to avoid gperf.
I had changed that function to return the token ID directly rather than
a pointer to the token descriptor structure, but that meant that the
test for "is this a reserved word" changed from checking the return
value against NULL, to checking that it wasn't negative.
And while I had converted the main token parser over, I missed the
special case of the typeof phrase handling. And since our dependency
chain for genksyms does not include the genksyms program itself
changing, my kernel rebuild didn't show the problem.
Fixes:
bb3290d91695 ("Remove gperf usage from toolchain")
Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 8 Sep 2017 17:17:20 +0000 (10:17 -0700)]
RDMA/netlink: clean up message validity array initializer
The fix in the parent made me look at that function, and react to how
illogical and illegible the array initializer was.
Use named array indexes to make it clearer what is going on, and make
the initializer not depend silently on the exact index numbers.
[ The initializer now also shows an odd inconsistency in the naming:
note the IWCM vs IWPM.. - Linus ]
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Doug Ledford <dledford@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Leon Romanovsky [Fri, 8 Sep 2017 10:02:26 +0000 (13:02 +0300)]
RDAM/netlink: Fix out-of-bound access while checking message validity
The netlink message sent with type == 0, which doesn't have any client
behind it, caused to the overflow in max_num_ops array.
Fix it by declaring zero number of ops for the first client.
Fixes:
c9901724a2f1 ("RDMA/netlink: Remove netlink clients infrastructure")
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Radim Krčmář [Fri, 8 Sep 2017 12:40:43 +0000 (14:40 +0200)]
Merge branch 'kvm-ppc-fixes' of git://git./linux/kernel/git/paulus/powerpc
This fix was intended for 4.13, but didn't get in because both
maintainers were on vacation.
Paul Mackerras:
"It adds mutual exclusion between list_add_rcu and list_del_rcu calls
on the kvm->arch.spapr_tce_tables list. Without this, userspace could
potentially trigger corruption of the list and cause a host crash or
worse."
Linus Torvalds [Fri, 8 Sep 2017 04:39:15 +0000 (21:39 -0700)]
Merge branch 'gperf-removal'
Remove our use of 'gperf' for generating perfect hashes from some of our
build tools.
This removal was prompted by Masahiro Yamada sending out a patch that
removes all our pre-generated files, and when I tested it, I noticed
that the gperf version I have (3.1) apparently generates code that no
longer works with out code-base because the function interfaces
generated by gperf have changed.
We really don't care that much, and the gperf people changed their
interfaces in ways that makes it annoying to work with them. Tools that
make it hard to use them should not be used, and the kernel is not at
all interested in some autoconf mess. So remove the gperf dependency
entirely.
It turns out that if you ignore the pre-generated files, the use of
gperf apparently saved us a whopping fifteen lines of code. It
obviously wasn't worth it, considering that the pre-generated files are
about 500 lines.
I sent this out as a patch about three weeks ago, and got absolutely
zero responses. So let's see if anybody notices now that I merge it.
Because there might be serious bugs here, but it WorksForMe(tm).
* gperf-removal:
Remove gperf usage from toolchain
Linus Torvalds [Fri, 8 Sep 2017 04:11:05 +0000 (21:11 -0700)]
Merge tag 'scsi-misc' of git://git./linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This is mostly updates of the usual suspects: lpfc, qla2xxx, hisi_sas,
megaraid_sas, zfcp and a host of minor updates.
The major driver change here is the elimination of the block based
cciss driver in favour of the SCSI based hpsa driver (which now drives
all the legacy cases cciss used to be required for). Plus a reset
handler clean up and the redo of the SAS SMP handler to use bsg lib"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (279 commits)
scsi: scsi-mq: Always unprepare before requeuing a request
scsi: Show .retries and .jiffies_at_alloc in debugfs
scsi: Improve requeuing behavior
scsi: Call scsi_initialize_rq() for filesystem requests
scsi: qla2xxx: Reset the logo flag, after target re-login.
scsi: qla2xxx: Fix slow mem alloc behind lock
scsi: qla2xxx: Clear fc4f_nvme flag
scsi: qla2xxx: add missing includes for qla_isr
scsi: qla2xxx: Fix an integer overflow in sysfs code
scsi: aacraid: report -ENOMEM to upper layer from aac_convert_sgraw2()
scsi: aacraid: get rid of one level of indentation
scsi: aacraid: fix indentation errors
scsi: storvsc: fix memory leak on ring buffer busy
scsi: scsi_transport_sas: switch to bsg-lib for SMP passthrough
scsi: smartpqi: remove the smp_handler stub
scsi: hpsa: remove the smp_handler stub
scsi: bsg-lib: pass the release callback through bsg_setup_queue
scsi: Rework handling of scsi_device.vpd_pg8[03]
scsi: Rework the code for caching Vital Product Data (VPD)
scsi: rcu: Introduce rcu_swap_protected()
...
Linus Torvalds [Fri, 8 Sep 2017 04:00:52 +0000 (21:00 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/pmladek/printk
Pull printk updates from Petr Mladek:
- Do not allow use of freed init data and code even when boot consoles
are forced to stay. Also check for the init memory more precisely.
- Some code clean up by starting contributors.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
printk: Clean up do_syslog() error handling
printk/console: Enhance the check for consoles using init memory
printk/console: Always disable boot consoles that use init memory before it is freed
printk: Modify operators of printed_len and text_len
Linus Torvalds [Fri, 8 Sep 2017 03:48:25 +0000 (20:48 -0700)]
Merge tag 'audit-pr-
20170907' of git://git./linux/kernel/git/pcmoore/audit
Pull audit updates from Paul Moore:
"A small pull request for audit this time, only four patches and only
two with any real code changes.
Those two changes are the removal of a pointless SELinux AVC
initialization audit event and a fix to improve the audit timestamp
overhead.
The other two patches are comment cleanup and administrative updates,
nothing very exciting.
Everything passes our tests"
* tag 'audit-pr-
20170907' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: update the function comments
selinux: remove AVC init audit log message
audit: update the audit info in MAINTAINERS
audit: Reduce overhead using a coarse clock
Linus Torvalds [Fri, 8 Sep 2017 03:35:29 +0000 (20:35 -0700)]
Merge tag 'secureexec-v4.14-rc1' of git://git./linux/kernel/git/kees/linux
Pull secureexec update from Kees Cook:
"This series has the ultimate goal of providing a sane stack rlimit
when running set*id processes.
To do this, the bprm_secureexec LSM hook is collapsed into the
bprm_set_creds hook so the secureexec-ness of an exec can be
determined early enough to make decisions about rlimits and the
resulting memory layouts. Other logic acting on the secureexec-ness of
an exec is similarly consolidated. Capabilities needed some special
handling, but the refactoring removed other special handling, so that
was a wash"
* tag 'secureexec-v4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
exec: Consolidate pdeath_signal clearing
exec: Use sane stack rlimit under secureexec
exec: Consolidate dumpability logic
smack: Remove redundant pdeath_signal clearing
exec: Use secureexec for clearing pdeath_signal
exec: Use secureexec for setting dumpability
LSM: drop bprm_secureexec hook
commoncap: Move cap_elevated calculation into bprm_set_creds
commoncap: Refactor to remove bprm_secureexec hook
smack: Refactor to remove bprm_secureexec hook
selinux: Refactor to remove bprm_secureexec hook
apparmor: Refactor to remove bprm_secureexec hook
binfmt: Introduce secureexec flag
exec: Correct comments about "point of no return"
exec: Rename bprm->cred_prepared to called_set_creds
Linus Torvalds [Fri, 8 Sep 2017 03:30:19 +0000 (20:30 -0700)]
Merge tag 'gcc-plugins-v4.14-rc1' of git://git./linux/kernel/git/kees/linux
Pull gcc plugins update from Kees Cook:
"This finishes the porting work on randstruct, and introduces a new
option to structleak, both noted below:
- For the randstruct plugin, enable automatic randomization of
structures that are entirely function pointers (along with a couple
designated initializer fixes).
- For the structleak plugin, provide an option to perform zeroing
initialization of all otherwise uninitialized stack variables that
are passed by reference (Ard Biesheuvel)"
* tag 'gcc-plugins-v4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
gcc-plugins: structleak: add option to init all vars used as byref args
randstruct: Enable function pointer struct detection
drivers/net/wan/z85230.c: Use designated initializers
drm/amd/powerplay: rv: Use designated initializers
Linus Torvalds [Fri, 8 Sep 2017 02:58:56 +0000 (19:58 -0700)]
Merge tag 'pstore-v4.14-rc1' of git://git./linux/kernel/git/kees/linux
Pull pstore update from Kees Cook:
"Make pstore permissions more versatile by removing CAP_SYSLOG
requirement and defining more restrictive root directory DAC
permissions default (0750, which can be adjust after boot unlike the
CAP_SYSLOG check).
Suggested by Nick Kralevich"
* tag 'pstore-v4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
Revert "pstore: Honor dmesg_restrict sysctl on dmesg dumps"
pstore: Make default pstorefs root dir perms 0750
Linus Torvalds [Thu, 7 Sep 2017 23:06:14 +0000 (16:06 -0700)]
Merge tag '4.14-smb3-xattr-enable' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs update from Steve French:
"Enable xattr support for smb3 and also a bugfix"
* tag '4.14-smb3-xattr-enable' of git://git.samba.org/sfrench/cifs-2.6:
cifs: Check for timeout on Negotiate stage
cifs: Add support for writing attributes on SMB2+
cifs: Add support for reading attributes on SMB2+
Linus Torvalds [Thu, 7 Sep 2017 22:51:11 +0000 (15:51 -0700)]
Merge git://git.kvack.org/~bcrl/aio-next
Pull aio fix from Ben LaHaise:
"Improve aio-nr counting on large SMP systems.
It has been in linux-next for quite some time"
* git://git.kvack.org/~bcrl/aio-next:
fs: aio: fix the increment of aio-nr and counting against aio-max-nr
Linus Torvalds [Thu, 7 Sep 2017 22:19:35 +0000 (15:19 -0700)]
Merge branch 'quota_scaling' of git://git./linux/kernel/git/jack/linux-fs
Pull quota scaling updates from Jan Kara:
"This contains changes to make the quota subsystem more scalable.
Reportedly it improves number of files created per second on ext4
filesystem on fast storage by about a factor of 2x"
* 'quota_scaling' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (28 commits)
quota: Add lock annotations to struct members
quota: Reduce contention on dq_data_lock
fs: Provide __inode_get_bytes()
quota: Inline dquot_[re]claim_reserved_space() into callsite
quota: Inline inode_{incr,decr}_space() into callsites
quota: Inline functions into their callsites
ext4: Disable dirty list tracking of dquots when journalling quotas
quota: Allow disabling tracking of dirty dquots in a list
quota: Remove dq_wait_unused from dquot
quota: Move locking into clear_dquot_dirty()
quota: Do not dirty bad dquots
quota: Fix possible corruption of dqi_flags
quota: Propagate ->quota_read errors from v2_read_file_info()
quota: Fix error codes in v2_read_file_info()
quota: Push dqio_sem down to ->read_file_info()
quota: Push dqio_sem down to ->write_file_info()
quota: Push dqio_sem down to ->get_next_id()
quota: Push dqio_sem down to ->release_dqblk()
quota: Remove locking for writing to the old quota format
quota: Do not acquire dqio_sem for dquot overwrites in v2 format
...
Linus Torvalds [Thu, 7 Sep 2017 21:53:17 +0000 (14:53 -0700)]
Merge branch 'for_linus' of git://git./linux/kernel/git/jack/linux-fs
Pull UDF, reiserfs, quota, fsnotify cleanups from Jan Kara:
"Several UDF, reiserfs, quota and fsnotify cleanups.
Note that there is also a patch updating MAINTAINERS entry for
notification subsystem to point to me as a maintainer since current
entries are stale"
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
fsnotify: make dnotify_fsnotify_ops const
isofs: Delete an unnecessary variable initialisation in isofs_read_inode()
isofs: Adjust four checks for null pointers
isofs: Delete an error message for a failed memory allocation in isofs_read_inode()
quota_v2: Delete an error message for a failed memory allocation in v2_read_file_info()
fs-udf: Delete an error message for a failed memory allocation in two functions
fs-udf: Improve six size determinations
fs-udf: Adjust two checks for null pointers
reiserfs: fix spelling mistake: "tranasction" -> "transaction"
MAINTAINERS: Update entries for notification subsystem
uapi/linux/quota.h: Do not include linux/errno.h
Linus Torvalds [Thu, 7 Sep 2017 21:43:33 +0000 (14:43 -0700)]
Merge tag 'devicetree-for-4.14' of git://git./linux/kernel/git/robh/linux
Pull DeviceTree updates from Rob Herring:
"There's a few orphans in the conversion to %pOF printf specifiers
included here that no one else picked up.
Summary:
- Convert more DT code to use of_property_read_* API.
- Improve DT overlay support when adding multiple overlays
- Convert printk's to %pOF format specifiers. Most went via subsystem
trees, but picked up the remaining orphans
- Correct unittests to use preferred "okay" for "status" property
value
- Add a KASLR seed property
- Vendor prefixes for Mellanox, Theobroma System, Adaptrum, Moxa
- Fix modalias buffer handling
- Clean-up of include paths for building dtbs
- Add bindings for amc6821, isl1208, tsl2x7x, srf02, and srf10
devices
- Add nvmem bindings for MediaTek MT7623 and MT7622 SoC
- Add compatible string for Allwinner H5 Mali-450 GPU
- Fix links to old OpenFirmware docs with new mirror on
devicetree.org
- Remove status property from binding doc examples"
* tag 'devicetree-for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (45 commits)
devicetree: Adjust status "ok" -> "okay" under drivers/of/
dt-bindings: Remove "status" from examples
dt-bindings: pinctrl: sh-pfc: Use generic node name
dt-bindings: Add vendor Mellanox
dt-binding: net/phy: fix interrupts description
virt: Convert to using %pOF instead of full_name
macintosh: Convert to using %pOF instead of full_name
ide: pmac: Convert to using %pOF instead of full_name
microblaze: Convert to using %pOF instead of full_name
dt-bindings: usb: musb: Grammar s/the/to/, s/is/are/
of: Use PLATFORM_DEVID_NONE definition
of/device: Fix of_device_get_modalias() buffer handling
of/device: Prevent buffer overflow in of_device_modalias()
dt-bindings: add amc6821, isl1208 trivial bindings
dt-bindings: add vendor prefix for Theobroma Systems
of: search scripts/dtc/include-prefixes path for both CPP and DTC
of: remove arch/$(SRCARCH)/boot/dts from include search path for CPP
of: remove drivers/of/testcase-data from include search path for CPP
of: return of_get_cpu_node from of_cpu_device_node_get if CPUs are not registered
iio: srf08: add device tree binding for srf02 and srf10
...
Linus Torvalds [Thu, 7 Sep 2017 21:37:25 +0000 (14:37 -0700)]
Merge tag 'drm-intel-next-fixes-2017-09-07' of git://anongit.freedesktop.org/git/drm-intel
Pull i916 drm fixes from Rodrigo Vivi:
"Since Dave is on paternity leave we are sending drm/i915 fixes for
v4.14-rc1 directly to you as he had asked us to do.
The most critical ones are the GPU reset fix for gen2-4 and GVT fix
for a regression that is blocking gvt init to work on your tree.
The rest is general fixes for patches coming from drm-next"
Acked-by: Dave Airlie <airlied@redhat.com>
* tag 'drm-intel-next-fixes-2017-09-07' of git://anongit.freedesktop.org/git/drm-intel:
drm/i915: Re-enable GTT following a device reset
drm/i915: Annotate user relocs with __user
drm/i915: Silence sparse by using gfp_t
drm/i915: Add __rcu to radix tree slot pointer
drm/i915: Fix the missing PPAT cache attributes on CNL
drm/i915/gvt: Remove one duplicated MMIO
drm/i915: Fix enum pipe vs. enum transcoder for the PCH transcoder
drm/i915: Make i2c lock ops static
drm/i915: Make i9xx_load_ycbcr_conversion_matrix() static
drm/i915/edp: Increase T12 panel delay to 900 ms to fix DP AUX CH timeouts
drm/i915: Ignore duplicate VMA stored within the per-object handle LUT
drm/i915: Skip fence alignemnt check for the CCS plane
drm/i915: Treat fb->offsets[] as a raw byte offset instead of a linear offset
drm/i915: Always wake the device to flush the GTT
drm/i915: Recreate vmapping even when the object is pinned
drm/i915: Quietly cancel FBC activation if CRTC is turned off before worker
Linus Torvalds [Thu, 7 Sep 2017 21:33:13 +0000 (14:33 -0700)]
Merge tag 'leds_for_4.14' of git://git./linux/kernel/git/j.anaszewski/linux-leds
Pull LED updates from Jacek Anaszewski:
"LED class drivers improvements:
leds-pca955x:
- add Device Tree support and bindings
- use devm_led_classdev_register()
- add GPIO support
- prevent crippled LED class device name
- check for I2C errors
leds-gpio:
- add optional retain-state-shutdown DT property
- allow LED to retain state at shutdown
leds-tlc591xx:
- merge conditional tests
- add missing of_node_put
leds-powernv:
- delete an error message for a failed memory allocation in
powernv_led_create()
leds-is31fl32xx.c
- convert to using custom %pOF printf format specifier
Constify attribute_group structures in:
- leds-blinkm
- leds-lm3533
Make several arrays static const in:
- leds-aat1290
- leds-lp5521
- leds-lp5562
- leds-lp8501"
* tag 'leds_for_4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
leds: pca955x: check for I2C errors
leds: gpio: Allow LED to retain state at shutdown
dt-bindings: leds: gpio: Add optional retain-state-shutdown property
leds: powernv: Delete an error message for a failed memory allocation in powernv_led_create()
leds: lp8501: make several arrays static const
leds: lp5562: make several arrays static const
leds: lp5521: make several arrays static const
leds: aat1290: make array max_mm_current_percent static const
leds: pca955x: Prevent crippled LED device name
leds: lm3533: constify attribute_group structure
dt-bindings: leds: add pca955x
leds: pca955x: add GPIO support
leds: pca955x: use devm_led_classdev_register
leds: pca955x: add device tree support
leds: Convert to using %pOF instead of full_name
leds: blinkm: constify attribute_group structures.
leds: tlc591xx: add missing of_node_put
leds: tlc591xx: merge conditional tests
Linus Torvalds [Thu, 7 Sep 2017 21:03:05 +0000 (14:03 -0700)]
Merge tag 'dmaengine-4.14-rc1' of git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine updates from Vinod Koul:
"This one features the usual updates to the drivers and one good part
of removing DA_SG from core as it has no users.
Summary:
- Remove DMA_SG support as we have no users for this feature
- New driver for Altera / Intel mSGDMA IP core
- Support for memset in dmatest and qcom_hidma driver
- Update for non cyclic mode in k3dma, bunch of update in bam_dma,
bcm sba-raid
- Constify device ids across drivers"
* tag 'dmaengine-4.14-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (52 commits)
dmaengine: sun6i: support V3s SoC variant
dmaengine: sun6i: make gate bit in sun8i's DMA engines a common quirk
dmaengine: rcar-dmac: document R8A77970 bindings
dmaengine: xilinx_dma: Fix error code format specifier
dmaengine: altera: Use macros instead of structs to describe the registers
dmaengine: ti-dma-crossbar: Fix dra7 reserve function
dmaengine: pl330: constify amba_id
dmaengine: pl08x: constify amba_id
dmaengine: bcm-sba-raid: Remove redundant SBA_REQUEST_STATE_COMPLETED
dmaengine: bcm-sba-raid: Explicitly ACK mailbox message after sending
dmaengine: bcm-sba-raid: Add debugfs support
dmaengine: bcm-sba-raid: Remove redundant SBA_REQUEST_STATE_RECEIVED
dmaengine: bcm-sba-raid: Re-factor sba_process_deferred_requests()
dmaengine: bcm-sba-raid: Pre-ack async tx descriptor
dmaengine: bcm-sba-raid: Peek mbox when we have no free requests
dmaengine: bcm-sba-raid: Alloc resources before registering DMA device
dmaengine: bcm-sba-raid: Improve sba_issue_pending() run duration
dmaengine: bcm-sba-raid: Increase number of free sba_request
dmaengine: bcm-sba-raid: Allow arbitrary number free sba_request
dmaengine: bcm-sba-raid: Remove reqs_free_count from sba_device
...
Linus Torvalds [Thu, 7 Sep 2017 20:55:16 +0000 (13:55 -0700)]
Merge tag 'backlight-next-4.14' of git://git./linux/kernel/git/lee/backlight
Pull backlight updates from Lee Jones:
"Fix-ups:
- Constification; pwm_bl
- Use new GPIO API; gpio_backlight
- Remove unused functionality; gpio_backlight
Bug Fixes:
- Fix artificial MAXREG limit; lm3630a_bl"
* tag 'backlight-next-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
backlight: gpio_backlight: Delete pdata inversion
backlight: gpio_backlight: Convert to use GPIO descriptor
backlight: pwm_bl: Make of_device_ids const
backlight: lm3630a: Bump REG_MAX value to 0x50 instead of 0x1F
Linus Torvalds [Thu, 7 Sep 2017 20:51:13 +0000 (13:51 -0700)]
Merge tag 'mfd-next-4.14' of git://git./linux/kernel/git/lee/mfd
Pull MFD updates from Lee Jones:
"New Drivers
- RK805 Power Management IC (PMIC)
- ROHM BD9571MWV-M MFD Power Management IC (PMIC)
- Texas Instruments TPS68470 Power Management IC (PMIC) & LEDs
New Device Support:
- Add support for HiSilicon Hi6421v530 to hi6421-pmic-core
- Add support for X-Powers AXP806 to axp20x
- Add support for X-Powers AXP813 to axp20x
- Add support for Intel Sunrise Point LPSS to intel-lpss-pci
New Functionality:
- Amend API to provide register layout; atmel-smc
Fix-ups:
- DT re-work; omap, nokia
- Header file location change {I2C => MFD}; dm355evm_msp, tps65010
- Fix chip ID formatting issue(s); rk808
- Optionally register touchscreen devices; da9052-core
- Documentation improvements; twl-core
- Constification; rtsx_pcr, ab8500-core, da9055-i2c, da9052-spi
- Drop unnecessary static declaration; max8925-i2c
- Kconfig changes (missing deps and remove module support)
- Slim down oversized licence statement; hi6421-pmic-core
- Use managed resources (devm_*); lp87565
- Supply proper error checking/handling; t7l66xb
Bug Fixes:
- Fix counter duplication issue; da9052-core
- Fix potential NULL deference issue; max8998
- Leave SPI-NOR write-protection bit alone; lpc_ich
- Ensure device is put into reset during suspend; intel-lpss
- Correct register offset variable size; omap-usb-tll"
* tag 'mfd-next-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (61 commits)
mfd: intel_soc_pmic: Differentiate between Bay and Cherry Trail CRC variants
mfd: intel_soc_pmic: Export separate mfd-cell configs for BYT and CHT
dt-bindings: mfd: Add bindings for ZII RAVE devices
mfd: omap-usb-tll: Fix register offsets
mfd: da9052: Constify spi_device_id
mfd: intel-lpss: Put I2C and SPI controllers into reset state on suspend
mfd: da9055: Constify i2c_device_id
mfd: intel-lpss: Add missing PCI ID for Intel Sunrise Point LPSS devices
mfd: t7l66xb: Handle return value of clk_prepare_enable
mfd: Add ROHM BD9571MWV-M PMIC DT bindings
mfd: intel_soc_pmic_chtwc: Turn Kconfig option into a bool
mfd: lp87565: Convert to use devm_mfd_add_devices()
mfd: Add support for TPS68470 device
mfd: lpc_ich: Do not touch SPI-NOR write protection bit on Haswell/Broadwell
mfd: syscon: atmel-smc: Add helper to retrieve register layout
mfd: axp20x: Use correct platform device ID for many PEK
dt-bindings: mfd: axp20x: Introduce bindings for AXP813
mfd: axp20x: Add support for AXP813 PMIC
dt-bindings: mfd: axp20x: Add AXP806 to supported list of chips
mfd: Add ROHM BD9571MWV-M MFD PMIC driver
...
Linus Torvalds [Thu, 7 Sep 2017 20:39:21 +0000 (13:39 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/dtor/input
Pull input updates from Dmitry Torokhov:
- a new GPIO bit-banging driver implementing PS/2 protocol
- a new power key driver for Rockchip RK805 PMIC
- bunch of patches constifying various device ID structures
- Elan I2C touchpad driver now supports devices with 2 buttons
- other assorted fixes
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (76 commits)
Input: byd - make array seq static, reduces object code size
Input: xilinx_ps2 - fix multiline comment style
Input: pxa27x_keypad - handle return value of clk_prepare_enable
Input: tegra-kbc - handle return value of clk_prepare_enable
Input: PS/2 gpio bit banging driver for serio bus
Input: xen-kbdfront - enable auto repeat for xen keyboard frontend driver
Input: ambakmi - constify amba_id
Input: atmel_mxt_ts - add support for reset line
Input: atmel_mxt_ts - use more managed resources
Input: wacom_w8001 - constify serio_device_id
Input: tsc40 - constify serio_device_id
Input: touchwin - constify serio_device_id
Input: touchright - constify serio_device_id
Input: touchit213 - constify serio_device_id
Input: penmount - constify serio_device_id
Input: mtouch - constify serio_device_id
Input: inexio - constify serio_device_id
Input: hampshire - constify serio_device_id
Input: gunze - constify serio_device_id
Input: fujitsu_ts - constify serio_device_id
...
Linus Torvalds [Thu, 7 Sep 2017 20:23:37 +0000 (13:23 -0700)]
Merge tag 'mailbox-v4.14' of git://git.linaro.org/landing-teams/working/fujitsu/integration
Pull mailbox updates from Jassi Brar:
"Just behavorial changes to a controller driver: the Broadcom's Flexrm
mailbox driver has been modifified to support debugfs and TX-Done
mechanism by ACK.
Nothing for the core mailbox stack"
* tag 'mailbox-v4.14' of git://git.linaro.org/landing-teams/working/fujitsu/integration:
mailbox: bcm-flexrm-mailbox: Use txdone_ack instead of txdone_poll
mailbox: bcm-flexrm-mailbox: Use bitmap instead of IDA
mailbox: bcm-flexrm-mailbox: Fix mask used in CMPL_START_ADDR_VALUE()
mailbox: bcm-flexrm-mailbox: Add debugfs support
mailbox: bcm-flexrm-mailbox: Set IRQ affinity hint for FlexRM ring IRQs
Linus Torvalds [Thu, 7 Sep 2017 19:53:14 +0000 (12:53 -0700)]
Merge tag 'media/v4.14-1' of git://git./linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab:
"Brazil's Independence Day pull request :-)
This is one of the biggest media pull requests, with 625 patches
affecting almost all parts of media (RC, DVB, V4L2, CEC, docs).
This contains:
- A lot of new drivers:
* DVB frontends: mxl5xx, stv0910, stv6111;
* camera flash: as3645a led driver;
* HDMI receiver: adv748X;
* camera sensor: Omnivision 6650 5M driver (ov6650);
* HDMI CEC: ao-cec meson driver;
* V4L2: Qualcom camss driver;
* Remote controller: gpio-ir-tx, pwm-ir-tx and zx-irdec drivers.
- The DDbridge DVB driver got a massive update, with makes it in sync
with modern hardware from that vendor;
- There's an important milestone on this series: the DVB
documentation was written in 2003, but only started to be updated
in 2007. It also used to contain several gaps from the time it was
kept out of tree, mentioning error codes and device nodes that
never existed upstream. On this series, it received a massive
update: all non-deprecated digital TV APIs are now in sync with the
current implementation;
- Some DVB APIs that aren't used by any upstream driver got removed;
- Other parts of the media documentation algo got updated, fixing
some bugs on its PDF output and making it compatible with Sphinx
version 1.6.
As the number of hacks required to build PDF output reduced, I hope
we'll have less troubles as newer versions of our documentation
toolchain are released (famous last words);
- As usual, lots of driver cleanups and improvements"
* tag 'media/v4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (624 commits)
media: leds: as3645a: add V4L2_FLASH_LED_CLASS dependency
media: get rid of removed DMX_GET_CAPS and DMX_SET_SOURCE leftovers
media: Revert "[media] v4l: async: make v4l2 coexist with devicetree nodes in a dt overlay"
media: staging: atomisp: sh_css_calloc shall return a pointer to the allocated space
media: Revert "[media] lirc_dev: remove superfluous get/put_device() calls"
media: add qcom_camss.rst to v4l-drivers rst file
media: dvb headers: make checkpatch happier
media: dvb uapi: move frontend legacy API to another part of the book
media: pixfmt-srggb12p.rst: better format the table for PDF output
media: docs-rst: media: Don't use \small for V4L2_PIX_FMT_SRGGB10 documentation
media: index.rst: don't write "Contents:" on PDF output
media: pixfmt*.rst: replace a two dots by a comma
media: vidioc-g-fmt.rst: adjust table format
media: vivid.rst: add a blank line to correct ReST format
media: v4l2 uapi book: get rid of driver programming's chapter
media: format.rst: use the right markup for important notes
media: docs-rst: cardlists: change their format to flat-tables
media: em28xx-cardlist.rst: update to reflect last changes
media: v4l2-event.rst: adjust table to fit on PDF output
media: docs: don't show ToC for each part on PDF output
...
Linus Torvalds [Thu, 7 Sep 2017 19:44:53 +0000 (12:44 -0700)]
Merge tag 'sound-4.14-rc1' of git://git./linux/kernel/git/tiwai/sound
Pull sound updates from Takashi Iwai:
"We have touched quite a lot of files but with fewer changes at this
cycle; as you can see, most of changes are trivial fixes, especially
constification patches.
Among the massive attacks by constification gangs, we had a few core
changes (mostly for ASoC core), as well the fixes and the updates by
major vendors.
Some highlights:
ALSA core:
- Fix possible races in control API user-TLV codes
- Small cleanup of PCM core
ASoC:
- Continued work for componentization; still half-baked, but we're
certainly progressing
- Use of devres for jack detection GPIOs, rather as a cleanup
- Jack detection support for Qualcomm MSM8916
- Support for Allwinner H3, Cirrus Logic CS43130, Intel Kabylake
systems with RT5663, Realtek RT274, TI TLV320AIC32x6 and Wolfson
WM8523"
* tag 'sound-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (512 commits)
ALSA: hda/ca0132 - Fix memory leak at error path
ALSA: hda: Fix forget to free resource in error handling code path in hda_codec_driver_probe
ASoC: cs43130: Fix unused compiler warnings for PM runtime
ASoC: cs43130: Fix possible Oops with invalid dev_id
ASoC: cs43130: fix spelling mistake: "irq_occurrance" -> "irq_occurrence"
ALSA: atmel: Remove leftovers of AVR32 removal
ALSA: atmel: convert AC97c driver to GPIO descriptor API
ALSA: hda/realtek - Enable jack detection function for Intel ALC700
ALSA: hda: Fix regression of hdmi eld control created based on invalid pcm
ASoC: Intel: Skylake: Add IPC to configure the copier secondary pins
ASoC: add missing compile rule for max98371
ASoC: add missing compile rule for sirf-audio-codec
ASoC: add missing compile rule for max98371
ASoC: cs43130: Add devicetree bindings for CS43130
ASoC: cs43130: Add support for CS43130 codec
ASoC: make clock direction configurable in asoc-simple
ALSA: ctxfi: Remove null check before kfree
ASoC: max98927: Changed device property read function
ASoC: max98927: Modified DAPM widget and map to enable/disable VI sense path
ASoC: max98927: Added PM suspend and resume function
...
Linus Torvalds [Thu, 7 Sep 2017 19:41:48 +0000 (12:41 -0700)]
Merge tag 'md/4.14-rc1' of git://git./linux/kernel/git/shli/md
Pull MD updates from Shaohua Li:
"This update mainly fixes bugs:
- Make raid5 ppl support several ppl from Pawel
- Several raid5-cache bug fixes from Song
- Bitmap fixes from Neil and Me
- One raid1/10 regression fix since 4.12 from Me
- Other small fixes and cleanup"
* tag 'md/4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
md/bitmap: disable bitmap_resize for file-backed bitmaps.
raid5-ppl: Recovery support for multiple partial parity logs
md: Runtime support for multiple ppls
md/raid0: attach correct cgroup info in bio
lib/raid6: align AVX512 constants to 512 bits, not bytes
raid5: remove raid5_build_block
md/r5cache: call mddev_lock/unlock() in r5c_journal_mode_show
md: replace seq_release_private with seq_release
md: notify about new spare disk in the container
md/raid1/10: reset bio allocated from mempool
md/raid5: release/flush io in raid5_do_work()
md/bitmap: copy correct data for bitmap super
Linus Torvalds [Thu, 7 Sep 2017 19:24:50 +0000 (12:24 -0700)]
Merge tag 'mmc-v4.14' of git://git./linux/kernel/git/ulfh/mmc
Pull MMC updates from Ulf Hansson:
"MMC core:
- Continue to refactor the mmc block code to prepare for blkmq
- Move mmc block debugfs into block module
- Next step for eMMC CMDQ by adding a new mmc host interface for it
- Move Kconfig option MMC_DEBUG from core to host
- Some additional minor improvements
MMC host:
- Declare structs as const when applicable
- Explicitly request exclusive reset control when applicable
- Improve some error paths and other various cleanups
- sdhci: Preparations to support SDHCI OMAP
- sdhci: Improve some PM related code
- sdhci: Re-factoring and modernizations
- sdhci-xenon: Add runtime PM and system sleep support
- sdhci-xenon: Add support for eMMC HS400 Enhanced Strobe
- sdhci-cadence: Add system sleep support
- sdhci-of-at91: Improve system sleep support
- dw_mmc: Add support for Hisilicon hi3660
- sunxi: Add support for A83T eMMC
- sunxi: Add support for DDR52 mode
- meson-gx: Add support for UHS-I SD-cards
- meson-gx: Cleanups and improvements
- tmio: Fix CMD12 (STOP) handling
- tmio: Cleanups and improvements
- renesas_sdhi: Add r8a7743/5 support
- renesas-sdhi: Add support for R-Car Gen3 SDHI DMAC
- renesas_sdhi: Cleanups and improvements"
* tag 'mmc-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: (145 commits)
mmc: renesas_sdhi: Add r8a7743/5 support
mmc: meson-gx: fix __ffsdi2 undefined on arm32
mmc: sdhci-xenon: add runtime pm support and reimplement standby
mmc: core: Move mmc_start_areq() declaration
mmc: mmci: stop building qcom dml as module
mmc: sunxi: Reset the device at probe time
clk: sunxi-ng: Provide a default reset hook
mmc: meson-gx: rework tuning function
mmc: meson-gx: change default tx phase
mmc: meson-gx: implement voltage switch callback
mmc: meson-gx: use CCF to handle the clock phases
mmc: meson-gx: implement card_busy callback
mmc: meson-gx: simplify interrupt handler
mmc: meson-gx: work around clk-stop issue
mmc: meson-gx: fix dual data rate mode frequencies
mmc: meson-gx: rework clock init function
mmc: meson-gx: rework clk_set function
mmc: meson-gx: rework set_ios function
mmc: meson-gx: cfg init overwrite values
mmc: meson-gx: initialize sane clk default before clock register
...
James Bottomley [Thu, 7 Sep 2017 19:12:43 +0000 (12:12 -0700)]
Merge branch 'fixes' into misc
Linus Torvalds [Thu, 7 Sep 2017 18:59:42 +0000 (11:59 -0700)]
Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:
"This is the first pull request for 4.14, containing most of the code
changes. It's a quiet series this round, which I think we needed after
the churn of the last few series. This contains:
- Fix for a registration race in loop, from Anton Volkov.
- Overflow complaint fix from Arnd for DAC960.
- Series of drbd changes from the usual suspects.
- Conversion of the stec/skd driver to blk-mq. From Bart.
- A few BFQ improvements/fixes from Paolo.
- CFQ improvement from Ritesh, allowing idling for group idle.
- A few fixes found by Dan's smatch, courtesy of Dan.
- A warning fixup for a race between changing the IO scheduler and
device remova. From David Jeffery.
- A few nbd fixes from Josef.
- Support for cgroup info in blktrace, from Shaohua.
- Also from Shaohua, new features in the null_blk driver to allow it
to actually hold data, among other things.
- Various corner cases and error handling fixes from Weiping Zhang.
- Improvements to the IO stats tracking for blk-mq from me. Can
drastically improve performance for fast devices and/or big
machines.
- Series from Christoph removing bi_bdev as being needed for IO
submission, in preparation for nvme multipathing code.
- Series from Bart, including various cleanups and fixes for switch
fall through case complaints"
* 'for-4.14/block' of git://git.kernel.dk/linux-block: (162 commits)
kernfs: checking for IS_ERR() instead of NULL
drbd: remove BIOSET_NEED_RESCUER flag from drbd_{md_,}io_bio_set
drbd: Fix allyesconfig build, fix recent commit
drbd: switch from kmalloc() to kmalloc_array()
drbd: abort drbd_start_resync if there is no connection
drbd: move global variables to drbd namespace and make some static
drbd: rename "usermode_helper" to "drbd_usermode_helper"
drbd: fix race between handshake and admin disconnect/down
drbd: fix potential deadlock when trying to detach during handshake
drbd: A single dot should be put into a sequence.
drbd: fix rmmod cleanup, remove _all_ debugfs entries
drbd: Use setup_timer() instead of init_timer() to simplify the code.
drbd: fix potential get_ldev/put_ldev refcount imbalance during attach
drbd: new disk-option disable-write-same
drbd: Fix resource role for newly created resources in events2
drbd: mark symbols static where possible
drbd: Send P_NEG_ACK upon write error in protocol != C
drbd: add explicit plugging when submitting batches
drbd: change list_for_each_safe to while(list_first_entry_or_null)
drbd: introduce drbd_recv_header_maybe_unplug
...
Linus Torvalds [Thu, 7 Sep 2017 17:24:21 +0000 (10:24 -0700)]
Merge tag 'for-linus-4.14b-rc1-tag' of git://git./linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross:
- the new pvcalls backend for routing socket calls from a guest to dom0
- some cleanups of Xen code
- a fix for wrong usage of {get,put}_cpu()
* tag 'for-linus-4.14b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (27 commits)
xen/mmu: set MMU_NORMAL_PT_UPDATE in remap_area_mfn_pte_fn
xen: Don't try to call xen_alloc_p2m_entry() on autotranslating guests
xen/events: events_fifo: Don't use {get,put}_cpu() in xen_evtchn_fifo_init()
xen/pvcalls: use WARN_ON(1) instead of __WARN()
xen: remove not used trace functions
xen: remove unused function xen_set_domain_pte()
xen: remove tests for pvh mode in pure pv paths
xen-platform: constify pci_device_id.
xen: cleanup xen.h
xen: introduce a Kconfig option to enable the pvcalls backend
xen/pvcalls: implement write
xen/pvcalls: implement read
xen/pvcalls: implement the ioworker functions
xen/pvcalls: disconnect and module_exit
xen/pvcalls: implement release command
xen/pvcalls: implement poll command
xen/pvcalls: implement accept command
xen/pvcalls: implement listen command
xen/pvcalls: implement bind command
xen/pvcalls: implement connect command
...
Linus Torvalds [Thu, 7 Sep 2017 17:15:40 +0000 (10:15 -0700)]
Merge tag 'powerpc-4.14-1' of git://git./linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Nothing really major this release, despite quite a lot of activity.
Just lots of things all over the place.
Some things of note include:
- Access via perf to a new type of PMU (IMC) on Power9, which can
count both core events as well as nest unit events (Memory
controller etc).
- Optimisations to the radix MMU TLB flushing, mostly to avoid
unnecessary Page Walk Cache (PWC) flushes when the structure of the
tree is not changing.
- Reworks/cleanups of do_page_fault() to modernise it and bring it
closer to other architectures where possible.
- Rework of our page table walking so that THP updates only need to
send IPIs to CPUs where the affected mm has run, rather than all
CPUs.
- The size of our vmalloc area is increased to 56T on 64-bit hash MMU
systems. This avoids problems with the percpu allocator on systems
with very sparse NUMA layouts.
- STRICT_KERNEL_RWX support on PPC32.
- A new sched domain topology for Power9, to capture the fact that
pairs of cores may share an L2 cache.
- Power9 support for VAS, which is a new mechanism for accessing
coprocessors, and initial support for using it with the NX
compression accelerator.
- Major work on the instruction emulation support, adding support for
many new instructions, and reworking it so it can be used to
implement the emulation needed to fixup alignment faults.
- Support for guests under PowerVM to use the Power9 XIVE interrupt
controller.
And probably that many things again that are almost as interesting,
but I had to keep the list short. Plus the usual fixes and cleanups as
always.
Thanks to: Alexey Kardashevskiy, Alistair Popple, Andreas Schwab,
Aneesh Kumar K.V, Anju T Sudhakar, Arvind Yadav, Balbir Singh,
Benjamin Herrenschmidt, Bhumika Goyal, Breno Leitao, Bryant G. Ly,
Christophe Leroy, Cédric Le Goater, Dan Carpenter, Dou Liyang,
Frederic Barrat, Gautham R. Shenoy, Geliang Tang, Geoff Levand, Hannes
Reinecke, Haren Myneni, Ivan Mikhaylov, John Allen, Julia Lawall,
LABBE Corentin, Laurentiu Tudor, Madhavan Srinivasan, Markus Elfring,
Masahiro Yamada, Matt Brown, Michael Neuling, Murilo Opsfelder Araujo,
Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran,
Paul Mackerras, Rashmica Gupta, Rob Herring, Rui Teng, Sam Bobroff,
Santosh Sivaraj, Scott Wood, Shilpasri G Bhat, Sukadev Bhattiprolu,
Suraj Jitindar Singh, Tobin C. Harding, Victor Aoqui"
* tag 'powerpc-4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (321 commits)
powerpc/xive: Fix section __init warning
powerpc: Fix kernel crash in emulation of vector loads and stores
powerpc/xive: improve debugging macros
powerpc/xive: add XIVE Exploitation Mode to CAS
powerpc/xive: introduce H_INT_ESB hcall
powerpc/xive: add the HW IRQ number under xive_irq_data
powerpc/xive: introduce xive_esb_write()
powerpc/xive: rename xive_poke_esb() in xive_esb_read()
powerpc/xive: guest exploitation of the XIVE interrupt controller
powerpc/xive: introduce a common routine xive_queue_page_alloc()
powerpc/sstep: Avoid used uninitialized error
axonram: Return directly after a failed kzalloc() in axon_ram_probe()
axonram: Improve a size determination in axon_ram_probe()
axonram: Delete an error message for a failed memory allocation in axon_ram_probe()
powerpc/powernv/npu: Move tlb flush before launching ATSD
powerpc/macintosh: constify wf_sensor_ops structures
powerpc/iommu: Use permission-specific DEVICE_ATTR variants
powerpc/eeh: Delete an error out of memory message at init time
powerpc/mm: Use seq_putc() in two functions
macintosh: Convert to using %pOF instead of full_name
...
Linus Torvalds [Thu, 7 Sep 2017 16:42:35 +0000 (09:42 -0700)]
Merge branch 'efi-core-for-linus' of git://git./linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
"The main changes in this cycle were:
- Transparently fall back to other poweroff method(s) if EFI poweroff
fails (and returns)
- Use separate PE/COFF section headers for the RX and RW parts of the
ARM stub loader so that the firmware can use strict mapping
permissions
- Add support for requesting the firmware to wipe RAM at warm reboot
- Increase the size of the random seed obtained from UEFI so CRNG
fast init can complete earlier
- Update the EFI framebuffer address if it points to a BAR that gets
moved by the PCI resource allocation code
- Enable "reset attack mitigation" of TPM environments: this is
enabled if the kernel is configured with
CONFIG_RESET_ATTACK_MITIGATION=y.
- Clang related fixes
- Misc cleanups, constification, refactoring, etc"
* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi/bgrt: Use efi_mem_type()
efi: Move efi_mem_type() to common code
efi/reboot: Make function pointer orig_pm_power_off static
efi/random: Increase size of firmware supplied randomness
efi/libstub: Enable reset attack mitigation
firmware/efi/esrt: Constify attribute_group structures
firmware/efi: Constify attribute_group structures
firmware/dcdbas: Constify attribute_group structures
arm/efi: Split zImage code and data into separate PE/COFF sections
arm/efi: Replace open coded constants with symbolic ones
arm/efi: Remove pointless dummy .reloc section
arm/efi: Remove forbidden values from the PE/COFF header
drivers/fbdev/efifb: Allow BAR to be moved instead of claiming it
efi/reboot: Fall back to original power-off method if EFI_RESET_SHUTDOWN returns
efi/arm/arm64: Add missing assignment of efi.config_table
efi/libstub/arm64: Set -fpie when building the EFI stub
efi/libstub/arm64: Force 'hidden' visibility for section markers
efi/libstub/arm64: Use hidden attribute for struct screen_info reference
efi/arm: Don't mark ACPI reclaim memory as MEMBLOCK_NOMAP
Radim Krčmář [Thu, 7 Sep 2017 16:29:01 +0000 (18:29 +0200)]
Merge branch 'kvm-ppc-next' of git://git./linux/kernel/git/paulus/powerpc
KVM/PPC update for 4.14
There are various minor fixes and cleanups. The only new feature is
that we now export information about storage key support to userspace,
so it can advertise it to the guest.
I have pulled in Michael Ellerman's topic/ppc-kvm branch from the
powerpc tree to get a couple of fixes that touch both KVM PPC code and
other PPC code. That's why there is some arch/powerpc stuff in the
diffstat that isn't arch/powerpc/kvm.
Mauricio Faria de Oliveira [Wed, 5 Jul 2017 13:53:16 +0000 (10:53 -0300)]
fs: aio: fix the increment of aio-nr and counting against aio-max-nr
Currently, aio-nr is incremented in steps of 'num_possible_cpus() * 8'
for io_setup(nr_events, ..) with 'nr_events < num_possible_cpus() * 4':
ioctx_alloc()
...
nr_events = max(nr_events, num_possible_cpus() * 4);
nr_events *= 2;
...
ctx->max_reqs = nr_events;
...
aio_nr += ctx->max_reqs;
....
This limits the number of aio contexts actually available to much less
than aio-max-nr, and is increasingly worse with greater number of CPUs.
For example, with 64 CPUs, only 256 aio contexts are actually available
(with aio-max-nr = 65536) because the increment is 512 in that scenario.
Note: 65536 [max aio contexts] / (64*4*2) [increment per aio context]
is 128, but make it 256 (double) as counting against 'aio-max-nr * 2':
ioctx_alloc()
...
if (aio_nr + nr_events > (aio_max_nr * 2UL) ||
...
goto err_ctx;
...
This patch uses the original value of nr_events (from userspace) to
increment aio-nr and count against aio-max-nr, which resolves those.
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Reported-by: Lekshmi C. Pillai <lekshmi.cpillai@in.ibm.com>
Tested-by: Lekshmi C. Pillai <lekshmi.cpillai@in.ibm.com>
Tested-by: Paul Nguyen <nguyenp@us.ibm.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Linus Torvalds [Thu, 7 Sep 2017 16:25:15 +0000 (09:25 -0700)]
Merge branch 'x86-platform-for-linus' of git://git./linux/kernel/git/tip/tip
Pull x86 platform updates from Ingo Molnar:
"The main changes include various Hyper-V optimizations such as faster
hypercalls and faster/better TLB flushes - and there's also some
Intel-MID cleanups"
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tracing/hyper-v: Trace hyperv_mmu_flush_tlb_others()
x86/hyper-v: Support extended CPU ranges for TLB flush hypercalls
x86/platform/intel-mid: Make several arrays static, to make code smaller
MAINTAINERS: Add missed file for Hyper-V
x86/hyper-v: Use hypercall for remote TLB flush
hyper-v: Globalize vp_index
x86/hyper-v: Implement rep hypercalls
hyper-v: Use fast hypercall for HVCALL_SIGNAL_EVENT
x86/hyper-v: Introduce fast hypercall implementation
x86/hyper-v: Make hv_do_hypercall() inline
x86/hyper-v: Include hyperv/ only when CONFIG_HYPERV is set
x86/platform/intel-mid: Make 'bt_sfi_data' const
x86/platform/intel-mid: Make IRQ allocation a bit more flexible
x86/platform/intel-mid: Group timers callbacks together
Radim Krčmář [Thu, 7 Sep 2017 16:22:04 +0000 (18:22 +0200)]
Merge tag 'kvm-arm-for-v4.14' of git://git./linux/kernel/git/kvmarm/kvmarm
KVM/ARM Changes for v4.14
Two minor cleanups and improvements, a fix for decoding external abort
types from guests, and added support for migrating the active priority
of interrupts when running a GICv2 guest on a GICv3 host.
Radim Krčmář [Thu, 7 Sep 2017 14:46:46 +0000 (16:46 +0200)]
Merge tag 'kvm-s390-next-4.14-2' of git://git./linux/kernel/git/kvms390/linux
KVM: s390: Fixes and features for 4.14
- merge of topic branch tlb-flushing from the s390 tree to get the
no-dat base features
- merge of kvm/master to avoid conflicts with additional sthyi fixes
- wire up the no-dat enhancements in KVM
- multiple epoch facility (z14 feature)
- Configuration z/Architecture Mode
- more sthyi fixes
- gdb server range checking fix
- small code cleanups
Linus Torvalds [Thu, 7 Sep 2017 05:41:21 +0000 (22:41 -0700)]
Merge branch 'for-4.14' of git://git./linux/kernel/git/tj/libata
Pull libata updates from Tejun Heo:
"Except for the ahci fix that fixes a boot issue, nothing major in this
pull request. Some new platform controller support and device specific
changes"
* 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
libata: zpodd: make arrays cdb static, reduces object code size
ahci: don't use MSI for devices with the silly Intel NVMe remapping scheme
dt-bindings: ata: add DT bindings for MediaTek SATA controller
ata: mediatek: add support for MediaTek SATA controller
pata_octeon_cf: use of_property_read_{bool|u32}()
cs5536: add support for IDE controller variant
ata: sata_gemini: Introduce explicit IDE pin control
ata: sata_gemini: Retire custom pin control
ata: ahci_platform: Add shutdown handler
ata: sata_gemini: explicitly request exclusive reset control
ata: Drop unnecessary static
ata: Convert to using %pOF instead of full_name
Linus Torvalds [Thu, 7 Sep 2017 05:25:25 +0000 (22:25 -0700)]
Merge branch 'for-4.14' of git://git./linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
"Several notable changes this cycle:
- Thread mode was merged. This will be used for cgroup2 support for
CPU and possibly other controllers. Unfortunately, CPU controller
cgroup2 support didn't make this pull request but most contentions
have been resolved and the support is likely to be merged before
the next merge window.
- cgroup.stat now shows the number of descendant cgroups.
- cpuset now can enable the easier-to-configure v2 behavior on v1
hierarchy"
* 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (21 commits)
cpuset: Allow v2 behavior in v1 cgroup
cgroup: Add mount flag to enable cpuset to use v2 behavior in v1 cgroup
cgroup: remove unneeded checks
cgroup: misc changes
cgroup: short-circuit cset_cgroup_from_root() on the default hierarchy
cgroup: re-use the parent pointer in cgroup_destroy_locked()
cgroup: add cgroup.stat interface with basic hierarchy stats
cgroup: implement hierarchy limits
cgroup: keep track of number of descent cgroups
cgroup: add comment to cgroup_enable_threaded()
cgroup: remove unnecessary empty check when enabling threaded mode
cgroup: update debug controller to print out thread mode information
cgroup: implement cgroup v2 thread support
cgroup: implement CSS_TASK_ITER_THREADED
cgroup: introduce cgroup->dom_cgrp and threaded css_set handling
cgroup: add @flags to css_task_iter_start() and implement CSS_TASK_ITER_PROCS
cgroup: reorganize cgroup.procs / task write path
cgroup: replace css_set walking populated test with testing cgrp->nr_populated_csets
cgroup: distinguish local and children populated states
cgroup: remove now unused list_head @pending in cgroup_apply_cftypes()
...
Linus Torvalds [Thu, 7 Sep 2017 04:59:31 +0000 (21:59 -0700)]
Merge branch 'for-4.14' of git://git./linux/kernel/git/tj/wq
Pull workqueue updates from Tejun Heo:
"Nothing major. I introduced a flag collsion bug during v4.13 cycle
which is fixed in this pull request. Fortunately, the flag is for
debugging / verification and the bug isn't critical"
* 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: Fix flag collision
workqueue: Use TASK_IDLE
workqueue: fix path to documentation
workqueue: doc change for ST behavior on NUMA systems
Linus Torvalds [Thu, 7 Sep 2017 04:33:12 +0000 (21:33 -0700)]
Merge branch 'for-4.14' of git://git./linux/kernel/git/tj/percpu
Pull percpu updates from Tejun Heo:
"A lot of changes for percpu this time around. percpu inherited the
same area allocator from the original pre-virtual-address-mapped
implementation. This was from the time when percpu allocator wasn't
used all that much and the implementation was focused on simplicity,
with the unfortunate computational complexity of O(number of areas
allocated from the chunk) per alloc / free.
With the increase in percpu usage, we're hitting cases where the lack
of scalability is hurting. The most prominent one right now is bpf
perpcu map creation / destruction which may allocate and free a lot of
entries consecutively and it's likely that the problem will become
more prominent in the future.
To address the issue, Dennis replaced the area allocator with hinted
bitmap allocator which is more consistent. While the new allocator
does perform a bit worse in some cases, it outperforms the old
allocator way more than an order of magnitude in other more common
scenarios while staying mostly flat in CPU overhead and completely
flat in memory consumption"
* 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (27 commits)
percpu: update header to contain bitmap allocator explanation.
percpu: update pcpu_find_block_fit to use an iterator
percpu: use metadata blocks to update the chunk contig hint
percpu: update free path to take advantage of contig hints
percpu: update alloc path to only scan if contig hints are broken
percpu: keep track of the best offset for contig hints
percpu: skip chunks if the alloc does not fit in the contig hint
percpu: add first_bit to keep track of the first free in the bitmap
percpu: introduce bitmap metadata blocks
percpu: replace area map allocator with bitmap
percpu: generalize bitmap (un)populated iterators
percpu: increase minimum percpu allocation size and align first regions
percpu: introduce nr_empty_pop_pages to help empty page accounting
percpu: change the number of pages marked in the first_chunk pop bitmap
percpu: combine percpu address checks
percpu: modify base_addr to be region specific
percpu: setup_first_chunk rename schunk/dchunk to chunk
percpu: end chunk area maps page aligned for the populated bitmap
percpu: unify allocation of schunk and dchunk
percpu: setup_first_chunk remove dyn_size and consolidate logic
...
Linus Torvalds [Thu, 7 Sep 2017 03:49:49 +0000 (20:49 -0700)]
Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:
- various misc bits
- DAX updates
- OCFS2
- most of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (119 commits)
mm,fork: introduce MADV_WIPEONFORK
x86,mpx: make mpx depend on x86-64 to free up VMA flag
mm: add /proc/pid/smaps_rollup
mm: hugetlb: clear target sub-page last when clearing huge page
mm: oom: let oom_reap_task and exit_mmap run concurrently
swap: choose swap device according to numa node
mm: replace TIF_MEMDIE checks by tsk_is_oom_victim
mm, oom: do not rely on TIF_MEMDIE for memory reserves access
z3fold: use per-cpu unbuddied lists
mm, swap: don't use VMA based swap readahead if HDD is used as swap
mm, swap: add sysfs interface for VMA based swap readahead
mm, swap: VMA based swap readahead
mm, swap: fix swap readahead marking
mm, swap: add swap readahead hit statistics
mm/vmalloc.c: don't reinvent the wheel but use existing llist API
mm/vmstat.c: fix wrong comment
selftests/memfd: add memfd_create hugetlbfs selftest
mm/shmem: add hugetlbfs support to memfd_create()
mm, devm_memremap_pages: use multi-order radix for ZONE_DEVICE lookups
mm/vmalloc.c: halve the number of comparisons performed in pcpu_get_vm_areas()
...
Andy Lutomirski [Thu, 7 Sep 2017 02:54:54 +0000 (19:54 -0700)]
x86/mm: Document how CR4.PCIDE restore works
While debugging a problem, I thought that using
cr4_set_bits_and_update_boot() to restore CR4.PCIDE would be
helpful. It turns out to be counterproductive.
Add a comment documenting how this works.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andy Lutomirski [Thu, 7 Sep 2017 02:54:53 +0000 (19:54 -0700)]
x86/mm: Reinitialize TLB state on hotplug and resume
When Linux brings a CPU down and back up, it switches to init_mm and then
loads swapper_pg_dir into CR3. With PCID enabled, this has the side effect
of masking off the ASID bits in CR3.
This can result in some confusion in the TLB handling code. If we
bring a CPU down and back up with any ASID other than 0, we end up
with the wrong ASID active on the CPU after resume. This could
cause our internal state to become corrupt, although major
corruption is unlikely because init_mm doesn't have any user pages.
More obviously, if CONFIG_DEBUG_VM=y, we'll trip over an assertion
in the next context switch. The result of *that* is a failure to
resume from suspend with probability 1 - 1/6^(cpus-1).
Fix it by reinitializing cpu_tlbstate on resume and CPU bringup.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Jiri Kosina <jikos@kernel.org>
Fixes:
10af6235e0d3 ("x86/mm: Implement PCID based optimization: try to preserve old TLB entries using PCID")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Baohong Liu [Tue, 5 Sep 2017 21:57:19 +0000 (16:57 -0500)]
tracing: Apply trace_clock changes to instance max buffer
Currently trace_clock timestamps are applied to both regular and max
buffers only for global trace. For instance trace, trace_clock
timestamps are applied only to regular buffer. But, regular and max
buffers can be swapped, for example, following a snapshot. So, for
instance trace, bad timestamps can be seen following a snapshot.
Let's apply trace_clock timestamps to instance max buffer as well.
Link: http://lkml.kernel.org/r/ebdb168d0be042dcdf51f81e696b17fabe3609c1.1504642143.git.tom.zanussi@linux.intel.com
Cc: stable@vger.kernel.org
Fixes:
277ba0446 ("tracing: Add interface to allow multiple trace buffers")
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Rik van Riel [Wed, 6 Sep 2017 23:25:15 +0000 (16:25 -0700)]
mm,fork: introduce MADV_WIPEONFORK
Introduce MADV_WIPEONFORK semantics, which result in a VMA being empty
in the child process after fork. This differs from MADV_DONTFORK in one
important way.
If a child process accesses memory that was MADV_WIPEONFORK, it will get
zeroes. The address ranges are still valid, they are just empty.
If a child process accesses memory that was MADV_DONTFORK, it will get a
segmentation fault, since those address ranges are no longer valid in
the child after fork.
Since MADV_DONTFORK also seems to be used to allow very large programs
to fork in systems with strict memory overcommit restrictions, changing
the semantics of MADV_DONTFORK might break existing programs.
MADV_WIPEONFORK only works on private, anonymous VMAs.
The use case is libraries that store or cache information, and want to
know that they need to regenerate it in the child process after fork.
Examples of this would be:
- systemd/pulseaudio API checks (fail after fork) (replacing a getpid
check, which is too slow without a PID cache)
- PKCS#11 API reinitialization check (mandated by specification)
- glibc's upcoming PRNG (reseed after fork)
- OpenSSL PRNG (reseed after fork)
The security benefits of a forking server having a re-inialized PRNG in
every child process are pretty obvious. However, due to libraries
having all kinds of internal state, and programs getting compiled with
many different versions of each library, it is unreasonable to expect
calling programs to re-initialize everything manually after fork.
A further complication is the proliferation of clone flags, programs
bypassing glibc's functions to call clone directly, and programs calling
unshare, causing the glibc pthread_atfork hook to not get called.
It would be better to have the kernel take care of this automatically.
The patch also adds MADV_KEEPONFORK, to undo the effects of a prior
MADV_WIPEONFORK.
This is similar to the OpenBSD minherit syscall with MAP_INHERIT_ZERO:
https://man.openbsd.org/minherit.2
[akpm@linux-foundation.org: numerically order arch/parisc/include/uapi/asm/mman.h #defines]
Link: http://lkml.kernel.org/r/20170811212829.29186-3-riel@redhat.com
Signed-off-by: Rik van Riel <riel@redhat.com>
Reported-by: Florian Weimer <fweimer@redhat.com>
Reported-by: Colm MacCártaigh <colm@allcosts.net>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Cc: <linux-api@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rik van Riel [Wed, 6 Sep 2017 23:25:11 +0000 (16:25 -0700)]
x86,mpx: make mpx depend on x86-64 to free up VMA flag
Patch series "mm,fork,security: introduce MADV_WIPEONFORK", v4.
If a child process accesses memory that was MADV_WIPEONFORK, it will get
zeroes. The address ranges are still valid, they are just empty.
If a child process accesses memory that was MADV_DONTFORK, it will get a
segmentation fault, since those address ranges are no longer valid in
the child after fork.
Since MADV_DONTFORK also seems to be used to allow very large programs
to fork in systems with strict memory overcommit restrictions, changing
the semantics of MADV_DONTFORK might break existing programs.
The use case is libraries that store or cache information, and want to
know that they need to regenerate it in the child process after fork.
Examples of this would be:
- systemd/pulseaudio API checks (fail after fork) (replacing a getpid
check, which is too slow without a PID cache)
- PKCS#11 API reinitialization check (mandated by specification)
- glibc's upcoming PRNG (reseed after fork)
- OpenSSL PRNG (reseed after fork)
The security benefits of a forking server having a re-inialized PRNG in
every child process are pretty obvious. However, due to libraries
having all kinds of internal state, and programs getting compiled with
many different versions of each library, it is unreasonable to expect
calling programs to re-initialize everything manually after fork.
A further complication is the proliferation of clone flags, programs
bypassing glibc's functions to call clone directly, and programs calling
unshare, causing the glibc pthread_atfork hook to not get called.
It would be better to have the kernel take care of this automatically.
The patchset also adds MADV_KEEPONFORK, to undo the effects of a prior
MADV_WIPEONFORK.
This is similar to the OpenBSD minherit syscall with MAP_INHERIT_ZERO:
https://man.openbsd.org/minherit.2
This patch (of 2):
MPX only seems to be available on 64 bit CPUs, starting with Skylake and
Goldmont. Move VM_MPX into the 64 bit only portion of vma->vm_flags, in
order to free up a VMA flag.
Link: http://lkml.kernel.org/r/20170811212829.29186-2-riel@redhat.com
Signed-off-by: Rik van Riel <riel@redhat.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Colm MacCártaigh <colm@allcosts.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Daniel Colascione [Wed, 6 Sep 2017 23:25:08 +0000 (16:25 -0700)]
mm: add /proc/pid/smaps_rollup
/proc/pid/smaps_rollup is a new proc file that improves the performance
of user programs that determine aggregate memory statistics (e.g., total
PSS) of a process.
Android regularly "samples" the memory usage of various processes in
order to balance its memory pool sizes. This sampling process involves
opening /proc/pid/smaps and summing certain fields. For very large
processes, sampling memory use this way can take several hundred
milliseconds, due mostly to the overhead of the seq_printf calls in
task_mmu.c.
smaps_rollup improves the situation. It contains most of the fields of
/proc/pid/smaps, but instead of a set of fields for each VMA,
smaps_rollup instead contains one synthetic smaps-format entry
representing the whole process. In the single smaps_rollup synthetic
entry, each field is the summation of the corresponding field in all of
the real-smaps VMAs. Using a common format for smaps_rollup and smaps
allows userspace parsers to repurpose parsers meant for use with
non-rollup smaps for smaps_rollup, and it allows userspace to switch
between smaps_rollup and smaps at runtime (say, based on the
availability of smaps_rollup in a given kernel) with minimal fuss.
By using smaps_rollup instead of smaps, a caller can avoid the
significant overhead of formatting, reading, and parsing each of a large
process's potentially very numerous memory mappings. For sampling
system_server's PSS in Android, we measured a 12x speedup, representing
a savings of several hundred milliseconds.
One alternative to a new per-process proc file would have been including
PSS information in /proc/pid/status. We considered this option but
thought that PSS would be too expensive (by a few orders of magnitude)
to collect relative to what's already emitted as part of
/proc/pid/status, and slowing every user of /proc/pid/status for the
sake of readers that happen to want PSS feels wrong.
The code itself works by reusing the existing VMA-walking framework we
use for regular smaps generation and keeping the mem_size_stats
structure around between VMA walks instead of using a fresh one for each
VMA. In this way, summation happens automatically. We let seq_file
walk over the VMAs just as it does for regular smaps and just emit
nothing to the seq_file until we hit the last VMA.
Benchmarks:
using smaps:
iterations:1000 pid:1163 pss:
220023808
0m29.46s real 0m08.28s user 0m20.98s system
using smaps_rollup:
iterations:1000 pid:1163 pss:
220702720
0m04.39s real 0m00.03s user 0m04.31s system
We're using the PSS samples we collect asynchronously for
system-management tasks like fine-tuning oom_adj_score, memory use
tracking for debugging, application-level memory-use attribution, and
deciding whether we want to kill large processes during system idle
maintenance windows. Android has been using PSS for these purposes for
a long time; as the average process VMA count has increased and and
devices become more efficiency-conscious, PSS-collection inefficiency
has started to matter more. IMHO, it'd be a lot safer to optimize the
existing PSS-collection model, which has been fine-tuned over the years,
instead of changing the memory tracking approach entirely to work around
smaps-generation inefficiency.
Tim said:
: There are two main reasons why Android gathers PSS information:
:
: 1. Android devices can show the user the amount of memory used per
: application via the settings app. This is a less important use case.
:
: 2. We log PSS to help identify leaks in applications. We have found
: an enormous number of bugs (in the Android platform, in Google's own
: apps, and in third-party applications) using this data.
:
: To do this, system_server (the main process in Android userspace) will
: sample the PSS of a process three seconds after it changes state (for
: example, app is launched and becomes the foreground application) and about
: every ten minutes after that. The net result is that PSS collection is
: regularly running on at least one process in the system (usually a few
: times a minute while the screen is on, less when screen is off due to
: suspend). PSS of a process is an incredibly useful stat to track, and we
: aren't going to get rid of it. We've looked at some very hacky approaches
: using RSS ("take the RSS of the target process, subtract the RSS of the
: zygote process that is the parent of all Android apps") to reduce the
: accounting time, but it regularly overestimated the memory used by 20+
: percent. Accordingly, I don't think that there's a good alternative to
: using PSS.
:
: We started looking into PSS collection performance after we noticed random
: frequency spikes while a phone's screen was off; occasionally, one of the
: CPU clusters would ramp to a high frequency because there was 200-300ms of
: constant CPU work from a single thread in the main Android userspace
: process. The work causing the spike (which is reasonable governor
: behavior given the amount of CPU time needed) was always PSS collection.
: As a result, Android is burning more power than we should be on PSS
: collection.
:
: The other issue (and why I'm less sure about improving smaps as a
: long-term solution) is that the number of VMAs per process has increased
: significantly from release to release. After trying to figure out why we
: were seeing these 200-300ms PSS collection times on Android O but had not
: noticed it in previous versions, we found that the number of VMAs in the
: main system process increased by 50% from Android N to Android O (from
: ~1800 to ~2700) and varying increases in every userspace process. Android
: M to N also had an increase in the number of VMAs, although not as much.
: I'm not sure why this is increasing so much over time, but thinking about
: ASLR and ways to make ASLR better, I expect that this will continue to
: increase going forward. I would not be surprised if we hit 5000 VMAs on
: the main Android process (system_server) by 2020.
:
: If we assume that the number of VMAs is going to increase over time, then
: doing anything we can do to reduce the overhead of each VMA during PSS
: collection seems like the right way to go, and that means outputting an
: aggregate statistic (to avoid whatever overhead there is per line in
: writing smaps and in reading each line from userspace).
Link: http://lkml.kernel.org/r/20170812022148.178293-1-dancol@google.com
Signed-off-by: Daniel Colascione <dancol@google.com>
Cc: Tim Murray <timmurray@google.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Sonny Rao <sonnyrao@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Huang Ying [Wed, 6 Sep 2017 23:25:04 +0000 (16:25 -0700)]
mm: hugetlb: clear target sub-page last when clearing huge page
Huge page helps to reduce TLB miss rate, but it has higher cache
footprint, sometimes this may cause some issue. For example, when
clearing huge page on x86_64 platform, the cache footprint is 2M. But
on a Xeon E5 v3 2699 CPU, there are 18 cores, 36 threads, and only 45M
LLC (last level cache). That is, in average, there are 2.5M LLC for
each core and 1.25M LLC for each thread.
If the cache pressure is heavy when clearing the huge page, and we clear
the huge page from the begin to the end, it is possible that the begin
of huge page is evicted from the cache after we finishing clearing the
end of the huge page. And it is possible for the application to access
the begin of the huge page after clearing the huge page.
To help the above situation, in this patch, when we clear a huge page,
the order to clear sub-pages is changed. In quite some situation, we
can get the address that the application will access after we clear the
huge page, for example, in a page fault handler. Instead of clearing
the huge page from begin to end, we will clear the sub-pages farthest
from the the sub-page to access firstly, and clear the sub-page to
access last. This will make the sub-page to access most cache-hot and
sub-pages around it more cache-hot too. If we cannot know the address
the application will access, the begin of the huge page is assumed to be
the the address the application will access.
With this patch, the throughput increases ~28.3% in vm-scalability
anon-w-seq test case with 72 processes on a 2 socket Xeon E5 v3 2699
system (36 cores, 72 threads). The test case creates 72 processes, each
process mmap a big anonymous memory area and writes to it from the begin
to the end. For each process, other processes could be seen as other
workload which generates heavy cache pressure. At the same time, the
cache miss rate reduced from ~33.4% to ~31.7%, the IPC (instruction per
cycle) increased from 0.56 to 0.74, and the time spent in user space is
reduced ~7.9%
Christopher Lameter suggests to clear bytes inside a sub-page from end
to begin too. But tests show no visible performance difference in the
tests. May because the size of page is small compared with the cache
size.
Thanks Andi Kleen to propose to use address to access to determine the
order of sub-pages to clear.
The hugetlbfs access address could be improved, will do that in another
patch.
[ying.huang@intel.com: improve readability of clear_huge_page()]
Link: http://lkml.kernel.org/r/20170830051842.1397-1-ying.huang@intel.com
Link: http://lkml.kernel.org/r/20170815014618.15842-1-ying.huang@intel.com
Suggested-by: Andi Kleen <andi.kleen@intel.com>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Acked-by: Jan Kara <jack@suse.cz>
Reviewed-by: Michal Hocko <mhocko@suse.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Nadia Yvette Chambers <nyc@holomorphy.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Shaohua Li <shli@fb.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrea Arcangeli [Wed, 6 Sep 2017 23:25:00 +0000 (16:25 -0700)]
mm: oom: let oom_reap_task and exit_mmap run concurrently
This is purely required because exit_aio() may block and exit_mmap() may
never start, if the oom_reap_task cannot start running on a mm with
mm_users == 0.
At the same time if the OOM reaper doesn't wait at all for the memory of
the current OOM candidate to be freed by exit_mmap->unmap_vmas, it would
generate a spurious OOM kill.
If it wasn't because of the exit_aio or similar blocking functions in
the last mmput, it would be enough to change the oom_reap_task() in the
case it finds mm_users == 0, to wait for a timeout or to wait for
__mmput to set MMF_OOM_SKIP itself, but it's not just exit_mmap the
problem here so the concurrency of exit_mmap and oom_reap_task is
apparently warranted.
It's a non standard runtime, exit_mmap() runs without mmap_sem, and
oom_reap_task runs with the mmap_sem for reading as usual (kind of
MADV_DONTNEED).
The race between the two is solved with a combination of
tsk_is_oom_victim() (serialized by task_lock) and MMF_OOM_SKIP
(serialized by a dummy down_write/up_write cycle on the same lines of
the ksm_exit method).
If the oom_reap_task() may be running concurrently during exit_mmap,
exit_mmap will wait it to finish in down_write (before taking down mm
structures that would make the oom_reap_task fail with use after free).
If exit_mmap comes first, oom_reap_task() will skip the mm if
MMF_OOM_SKIP is already set and in turn all memory is already freed and
furthermore the mm data structures may already have been taken down by
free_pgtables.
[aarcange@redhat.com: incremental one liner]
Link: http://lkml.kernel.org/r/20170726164319.GC29716@redhat.com
[rientjes@google.com: remove unused mmput_async]
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1708141733130.50317@chino.kir.corp.google.com
[aarcange@redhat.com: microoptimization]
Link: http://lkml.kernel.org/r/20170817171240.GB5066@redhat.com
Link: http://lkml.kernel.org/r/20170726162912.GA29716@redhat.com
Fixes:
26db62f179d1 ("oom: keep mm of the killed task available")
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: David Rientjes <rientjes@google.com>
Tested-by: David Rientjes <rientjes@google.com>
Reviewed-by: Michal Hocko <mhocko@suse.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Aaron Lu [Wed, 6 Sep 2017 23:24:57 +0000 (16:24 -0700)]
swap: choose swap device according to numa node
If the system has more than one swap device and swap device has the node
information, we can make use of this information to decide which swap
device to use in get_swap_pages() to get better performance.
The current code uses a priority based list, swap_avail_list, to decide
which swap device to use and if multiple swap devices share the same
priority, they are used round robin. This patch changes the previous
single global swap_avail_list into a per-numa-node list, i.e. for each
numa node, it sees its own priority based list of available swap
devices. Swap device's priority can be promoted on its matching node's
swap_avail_list.
The current swap device's priority is set as: user can set a >=0 value,
or the system will pick one starting from -1 then downwards. The
priority value in the swap_avail_list is the negated value of the swap
device's due to plist being sorted from low to high. The new policy
doesn't change the semantics for priority >=0 cases, the previous
starting from -1 then downwards now becomes starting from -2 then
downwards and -1 is reserved as the promoted value.
Take 4-node EX machine as an example, suppose 4 swap devices are
available, each sit on a different node:
swapA on node 0
swapB on node 1
swapC on node 2
swapD on node 3
After they are all swapped on in the sequence of ABCD.
Current behaviour:
their priorities will be:
swapA: -1
swapB: -2
swapC: -3
swapD: -4
And their position in the global swap_avail_list will be:
swapA -> swapB -> swapC -> swapD
prio:1 prio:2 prio:3 prio:4
New behaviour:
their priorities will be(note that -1 is skipped):
swapA: -2
swapB: -3
swapC: -4
swapD: -5
And their positions in the 4 swap_avail_lists[nid] will be:
swap_avail_lists[0]: /* node 0's available swap device list */
swapA -> swapB -> swapC -> swapD
prio:1 prio:3 prio:4 prio:5
swap_avali_lists[1]: /* node 1's available swap device list */
swapB -> swapA -> swapC -> swapD
prio:1 prio:2 prio:4 prio:5
swap_avail_lists[2]: /* node 2's available swap device list */
swapC -> swapA -> swapB -> swapD
prio:1 prio:2 prio:3 prio:5
swap_avail_lists[3]: /* node 3's available swap device list */
swapD -> swapA -> swapB -> swapC
prio:1 prio:2 prio:3 prio:4
To see the effect of the patch, a test that starts N process, each mmap
a region of anonymous memory and then continually write to it at random
position to trigger both swap in and out is used.
On a 2 node Skylake EP machine with 64GiB memory, two 170GB SSD drives
are used as swap devices with each attached to a different node, the
result is:
runtime=30m/processes=32/total test size=128G/each process mmap region=4G
kernel throughput
vanilla 13306
auto-binding 15169 +14%
runtime=30m/processes=64/total test size=128G/each process mmap region=2G
kernel throughput
vanilla 11885
auto-binding 14879 +25%
[aaron.lu@intel.com: v2]
Link: http://lkml.kernel.org/r/20170814053130.GD2369@aaronlu.sh.intel.com
Link: http://lkml.kernel.org/r/20170816024439.GA10925@aaronlu.sh.intel.com
[akpm@linux-foundation.org: use kmalloc_array()]
Link: http://lkml.kernel.org/r/20170814053130.GD2369@aaronlu.sh.intel.com
Link: http://lkml.kernel.org/r/20170816024439.GA10925@aaronlu.sh.intel.com
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Cc: "Chen, Tim C" <tim.c.chen@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Wed, 6 Sep 2017 23:24:53 +0000 (16:24 -0700)]
mm: replace TIF_MEMDIE checks by tsk_is_oom_victim
TIF_MEMDIE is set only to the tasks whick were either directly selected
by the OOM killer or passed through mark_oom_victim from the allocator
path. tsk_is_oom_victim is more generic and allows to identify all
tasks (threads) which share the mm with the oom victim.
Please note that the freezer still needs to check TIF_MEMDIE because we
cannot thaw tasks which do not participage in oom_victims counting
otherwise a !TIF_MEMDIE task could interfere after oom_disbale returns.
Link: http://lkml.kernel.org/r/20170810075019.28998-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Wed, 6 Sep 2017 23:24:50 +0000 (16:24 -0700)]
mm, oom: do not rely on TIF_MEMDIE for memory reserves access
For ages we have been relying on TIF_MEMDIE thread flag to mark OOM
victims and then, among other things, to give these threads full access
to memory reserves. There are few shortcomings of this implementation,
though.
First of all and the most serious one is that the full access to memory
reserves is quite dangerous because we leave no safety room for the
system to operate and potentially do last emergency steps to move on.
Secondly this flag is per task_struct while the OOM killer operates on
mm_struct granularity so all processes sharing the given mm are killed.
Giving the full access to all these task_structs could lead to a quick
memory reserves depletion. We have tried to reduce this risk by giving
TIF_MEMDIE only to the main thread and the currently allocating task but
that doesn't really solve this problem while it surely opens up a room
for corner cases - e.g. GFP_NO{FS,IO} requests might loop inside the
allocator without access to memory reserves because a particular thread
was not the group leader.
Now that we have the oom reaper and that all oom victims are reapable
after
1b51e65eab64 ("oom, oom_reaper: allow to reap mm shared by the
kthreads") we can be more conservative and grant only partial access to
memory reserves because there are reasonable chances of the parallel
memory freeing. We still want some access to reserves because we do not
want other consumers to eat up the victim's freed memory. oom victims
will still contend with __GFP_HIGH users but those shouldn't be so
aggressive to starve oom victims completely.
Introduce ALLOC_OOM flag and give all tsk_is_oom_victim tasks access to
the half of the reserves. This makes the access to reserves independent
on which task has passed through mark_oom_victim. Also drop any usage
of TIF_MEMDIE from the page allocator proper and replace it by
tsk_is_oom_victim as well which will make page_alloc.c completely
TIF_MEMDIE free finally.
CONFIG_MMU=n doesn't have oom reaper so let's stick to the original
ALLOC_NO_WATERMARKS approach.
There is a demand to make the oom killer memcg aware which will imply
many tasks killed at once. This change will allow such a usecase
without worrying about complete memory reserves depletion.
Link: http://lkml.kernel.org/r/20170810075019.28998-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vitaly Wool [Wed, 6 Sep 2017 23:24:47 +0000 (16:24 -0700)]
z3fold: use per-cpu unbuddied lists
It's been noted that z3fold doesn't scale well when it's run in a large
number of threads on many cores, which can be easily reproduced with fio
'randrw' test with --numjobs=32. E.g. the result for 1 cluster (4 cores)
is:
Run status group 0 (all jobs):
READ: io=244785MB, aggrb=496883KB/s, minb=15527KB/s, ...
WRITE: io=246735MB, aggrb=500841KB/s, minb=15651KB/s, ...
While for 8 cores (2 clusters) the result is:
Run status group 0 (all jobs):
READ: io=244785MB, aggrb=265942KB/s, minb=8310KB/s, ...
WRITE: io=246735MB, aggrb=268060KB/s, minb=8376KB/s, ...
The bottleneck here is the pool lock which many threads become waiting
upon. To reduce that spin lock contention, z3fold can operate only on
the lists local to the current CPU whenever possible. Due to the nature
of z3fold unbuddied list handling (it only takes the first entry off the
list on a hot path), if the z3fold pool is big enough and balanced well
enough, limiting search to only local unbuddied list doesn't lead to a
significant compression ratio degrade (2.57x vs 2.65x in our
measurements).
This patch also introduces two worker threads: one for async in-page
object layout optimization and one for releasing freed pages. This is
done to speed up z3fold_free() which is often on a hot path.
The fio results for 8-core case are now the following:
Run status group 0 (all jobs):
READ: io=244785MB, aggrb=1568.3MB/s, minb=50182KB/s, ...
WRITE: io=246735MB, aggrb=1580.8MB/s, minb=50582KB/s, ...
So we're in for almost 6x performance increase.
Link: http://lkml.kernel.org/r/20170806181443.f9b65018f8bde25ef990f9e8@gmail.com
Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Huang Ying [Wed, 6 Sep 2017 23:24:43 +0000 (16:24 -0700)]
mm, swap: don't use VMA based swap readahead if HDD is used as swap
VMA based swap readahead will readahead the virtual pages that is
continuous in the virtual address space. While the original swap
readahead will readahead the swap slots that is continuous in the swap
device. Although VMA based swap readahead is more correct for the swap
slots to be readahead, it will trigger more small random readings, which
may cause the performance of HDD (hard disk) to degrade heavily, and may
finally exceed the benefit.
To avoid the issue, in this patch, if the HDD is used as swap, the VMA
based swap readahead will be disabled, and the original swap readahead
will be used instead.
Link: http://lkml.kernel.org/r/20170807054038.1843-6-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Tim Chen <tim.c.chen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Huang Ying [Wed, 6 Sep 2017 23:24:40 +0000 (16:24 -0700)]
mm, swap: add sysfs interface for VMA based swap readahead
The sysfs interface to control the VMA based swap readahead is added as
follow,
/sys/kernel/mm/swap/vma_ra_enabled
Enable the VMA based swap readahead algorithm, or use the original
global swap readahead algorithm.
/sys/kernel/mm/swap/vma_ra_max_order
Set the max order of the readahead window size for the VMA based swap
readahead algorithm.
The corresponding ABI documentation is added too.
Link: http://lkml.kernel.org/r/20170807054038.1843-5-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Tim Chen <tim.c.chen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Huang Ying [Wed, 6 Sep 2017 23:24:36 +0000 (16:24 -0700)]
mm, swap: VMA based swap readahead
The swap readahead is an important mechanism to reduce the swap in
latency. Although pure sequential memory access pattern isn't very
popular for anonymous memory, the space locality is still considered
valid.
In the original swap readahead implementation, the consecutive blocks in
swap device are readahead based on the global space locality estimation.
But the consecutive blocks in swap device just reflect the order of page
reclaiming, don't necessarily reflect the access pattern in virtual
memory. And the different tasks in the system may have different access
patterns, which makes the global space locality estimation incorrect.
In this patch, when page fault occurs, the virtual pages near the fault
address will be readahead instead of the swap slots near the fault swap
slot in swap device. This avoid to readahead the unrelated swap slots.
At the same time, the swap readahead is changed to work on per-VMA from
globally. So that the different access patterns of the different VMAs
could be distinguished, and the different readahead policy could be
applied accordingly. The original core readahead detection and scaling
algorithm is reused, because it is an effect algorithm to detect the
space locality.
The test and result is as follow,
Common test condition
=====================
Test Machine: Xeon E5 v3 (2 sockets, 72 threads, 32G RAM) Swap device:
NVMe disk
Micro-benchmark with combined access pattern
============================================
vm-scalability, sequential swap test case, 4 processes to eat 50G
virtual memory space, repeat the sequential memory writing until 300
seconds. The first round writing will trigger swap out, the following
rounds will trigger sequential swap in and out.
At the same time, run vm-scalability random swap test case in
background, 8 processes to eat 30G virtual memory space, repeat the
random memory write until 300 seconds. This will trigger random swap-in
in the background.
This is a combined workload with sequential and random memory accessing
at the same time. The result (for sequential workload) is as follow,
Base Optimized
---- ---------
throughput 345413 KB/s 414029 KB/s (+19.9%)
latency.average 97.14 us 61.06 us (-37.1%)
latency.50th 2 us 1 us
latency.60th 2 us 1 us
latency.70th 98 us 2 us
latency.80th 160 us 2 us
latency.90th 260 us 217 us
latency.95th 346 us 369 us
latency.99th 1.34 ms 1.09 ms
ra_hit% 52.69% 99.98%
The original swap readahead algorithm is confused by the background
random access workload, so readahead hit rate is lower. The VMA-base
readahead algorithm works much better.
Linpack
=======
The test memory size is bigger than RAM to trigger swapping.
Base Optimized
---- ---------
elapsed_time 393.49 s 329.88 s (-16.2%)
ra_hit% 86.21% 98.82%
The score of base and optimized kernel hasn't visible changes. But the
elapsed time reduced and readahead hit rate improved, so the optimized
kernel runs better for startup and tear down stages. And the absolute
value of readahead hit rate is high, shows that the space locality is
still valid in some practical workloads.
Link: http://lkml.kernel.org/r/20170807054038.1843-4-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Tim Chen <tim.c.chen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Huang Ying [Wed, 6 Sep 2017 23:24:33 +0000 (16:24 -0700)]
mm, swap: fix swap readahead marking
In the original implementation, it is possible that the existing pages
in the swap cache (not newly readahead) could be marked as the readahead
pages. This will cause the statistics of swap readahead be wrong and
influence the swap readahead algorithm too.
This is fixed via marking a page as the readahead page only if it is
newly allocated and read from the disk.
When testing with linpack, after the fixing the swap readahead hit rate
increased from ~66% to ~86%.
Link: http://lkml.kernel.org/r/20170807054038.1843-3-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Tim Chen <tim.c.chen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Huang Ying [Wed, 6 Sep 2017 23:24:29 +0000 (16:24 -0700)]
mm, swap: add swap readahead hit statistics
Patch series "mm, swap: VMA based swap readahead", v4.
The swap readahead is an important mechanism to reduce the swap in
latency. Although pure sequential memory access pattern isn't very
popular for anonymous memory, the space locality is still considered
valid.
In the original swap readahead implementation, the consecutive blocks in
swap device are readahead based on the global space locality estimation.
But the consecutive blocks in swap device just reflect the order of page
reclaiming, don't necessarily reflect the access pattern in virtual
memory space. And the different tasks in the system may have different
access patterns, which makes the global space locality estimation
incorrect.
In this patchset, when page fault occurs, the virtual pages near the
fault address will be readahead instead of the swap slots near the fault
swap slot in swap device. This avoid to readahead the unrelated swap
slots. At the same time, the swap readahead is changed to work on
per-VMA from globally. So that the different access patterns of the
different VMAs could be distinguished, and the different readahead
policy could be applied accordingly. The original core readahead
detection and scaling algorithm is reused, because it is an effect
algorithm to detect the space locality.
In addition to the swap readahead changes, some new sysfs interface is
added to show the efficiency of the readahead algorithm and some other
swap statistics.
This new implementation will incur more small random read, on SSD, the
improved correctness of estimation and readahead target should beat the
potential increased overhead, this is also illustrated in the test
results below. But on HDD, the overhead may beat the benefit, so the
original implementation will be used by default.
The test and result is as follow,
Common test condition
=====================
Test Machine: Xeon E5 v3 (2 sockets, 72 threads, 32G RAM)
Swap device: NVMe disk
Micro-benchmark with combined access pattern
============================================
vm-scalability, sequential swap test case, 4 processes to eat 50G
virtual memory space, repeat the sequential memory writing until 300
seconds. The first round writing will trigger swap out, the following
rounds will trigger sequential swap in and out.
At the same time, run vm-scalability random swap test case in
background, 8 processes to eat 30G virtual memory space, repeat the
random memory write until 300 seconds. This will trigger random swap-in
in the background.
This is a combined workload with sequential and random memory accessing
at the same time. The result (for sequential workload) is as follow,
Base Optimized
---- ---------
throughput 345413 KB/s 414029 KB/s (+19.9%)
latency.average 97.14 us 61.06 us (-37.1%)
latency.50th 2 us 1 us
latency.60th 2 us 1 us
latency.70th 98 us 2 us
latency.80th 160 us 2 us
latency.90th 260 us 217 us
latency.95th 346 us 369 us
latency.99th 1.34 ms 1.09 ms
ra_hit% 52.69% 99.98%
The original swap readahead algorithm is confused by the background
random access workload, so readahead hit rate is lower. The VMA-base
readahead algorithm works much better.
Linpack
=======
The test memory size is bigger than RAM to trigger swapping.
Base Optimized
---- ---------
elapsed_time 393.49 s 329.88 s (-16.2%)
ra_hit% 86.21% 98.82%
The score of base and optimized kernel hasn't visible changes. But the
elapsed time reduced and readahead hit rate improved, so the optimized
kernel runs better for startup and tear down stages. And the absolute
value of readahead hit rate is high, shows that the space locality is
still valid in some practical workloads.
This patch (of 5):
The statistics for total readahead pages and total readahead hits are
recorded and exported via the following sysfs interface.
/sys/kernel/mm/swap/ra_hits
/sys/kernel/mm/swap/ra_total
With them, the efficiency of the swap readahead could be measured, so
that the swap readahead algorithm and parameters could be tuned
accordingly.
[akpm@linux-foundation.org: don't display swap stats if CONFIG_SWAP=n]
Link: http://lkml.kernel.org/r/20170807054038.1843-2-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Tim Chen <tim.c.chen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Byungchul Park [Wed, 6 Sep 2017 23:24:26 +0000 (16:24 -0700)]
mm/vmalloc.c: don't reinvent the wheel but use existing llist API
Although llist provides proper APIs, they are not used. Make them used.
Link: http://lkml.kernel.org/r/1502095374-16112-1-git-send-email-byungchul.park@lge.com
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Cc: zijun_hu <zijun_hu@htc.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SeongJae Park [Wed, 6 Sep 2017 23:24:23 +0000 (16:24 -0700)]
mm/vmstat.c: fix wrong comment
Comment for pagetypeinfo_showblockcount() is mistakenly duplicated from
pagetypeinfo_show_free()'s comment. This commit fixes it.
Link: http://lkml.kernel.org/r/20170809185816.11244-1-sj38.park@gmail.com
Fixes:
467c996c1e19 ("Print out statistics in relation to fragmentation avoidance to /proc/pagetypeinfo")
Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mike Kravetz [Wed, 6 Sep 2017 23:24:19 +0000 (16:24 -0700)]
selftests/memfd: add memfd_create hugetlbfs selftest
With the addition of hugetlbfs support in memfd_create, the memfd
selftests should verify correct functionality with hugetlbfs.
Instead of writing a separate memfd hugetlbfs test, modify the
memfd_test program to take an optional argument 'hugetlbfs'. If the
hugetlbfs argument is specified, basic memfd_create functionality will
be exercised on hugetlbfs. If hugetlbfs is not specified, the current
functionality of the test is unchanged.
Note that many of the tests in memfd_test test file sealing operations.
hugetlbfs does not support file sealing, therefore for hugetlbfs all
sealing related tests are skipped.
In order to test on hugetlbfs, there needs to be preallocated huge
pages. A new script (run_tests) is added. This script will first run
the existing memfd_create tests. It will then, attempt to allocate the
required number of huge pages before running the hugetlbfs test. At the
end of testing, it will release any huge pages allocated for testing
purposes.
Link: http://lkml.kernel.org/r/1502495772-24736-3-git-send-email-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mike Kravetz [Wed, 6 Sep 2017 23:24:16 +0000 (16:24 -0700)]
mm/shmem: add hugetlbfs support to memfd_create()
This patch came out of discussions in this e-mail thread:
http://lkml.kernel.org/r/
1499357846-7481-1-git-send-email-mike.kravetz%40oracle.com
The Oracle JVM team is developing a new garbage collection model. This
new model requires multiple mappings of the same anonymous memory. One
straight forward way to accomplish this is with memfd_create. They can
use the returned fd to create multiple mappings of the same memory.
The JVM today has an option to use (static hugetlb) huge pages. If this
option is specified, they would like to use the same garbage collection
model requiring multiple mappings to the same memory. Using hugetlbfs,
it is possible to explicitly mount a filesystem and specify file paths
in order to get an fd that can be used for multiple mappings. However,
this introduces additional system admin work and coordination.
Ideally they would like to get a hugetlbfs fd without requiring explicit
mounting of a filesystem. Today, mmap and shmget can make use of
hugetlbfs without explicitly mounting a filesystem. The patch adds this
functionality to memfd_create.
Add a new flag MFD_HUGETLB to memfd_create() that will specify the file
to be created resides in the hugetlbfs filesystem. This is the generic
hugetlbfs filesystem not associated with any specific mount point. As
with other system calls that request hugetlbfs backed pages, there is
the ability to encode huge page size in the flag arguments.
hugetlbfs does not support sealing operations, therefore specifying
MFD_ALLOW_SEALING with MFD_HUGETLB will result in EINVAL.
Of course, the memfd_man page would need updating if this type of
functionality moves forward.
Link: http://lkml.kernel.org/r/1502149672-7759-2-git-send-email-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dan Williams [Wed, 6 Sep 2017 23:24:13 +0000 (16:24 -0700)]
mm, devm_memremap_pages: use multi-order radix for ZONE_DEVICE lookups
devm_memremap_pages() records mapped ranges in pgmap_radix with an entry
per section's worth of memory (128MB). The key for each of those
entries is a section number.
This leads to false positives when devm_memremap_pages() is passed a
section-unaligned range as lookups in the misalignment fail to return
NULL. We can close this hole by using the pfn as the key for entries in
the tree. The number of entries required to describe a remapped range
is reduced by leveraging multi-order entries.
In practice this approach usually yields just one entry in the tree if
the size and starting address are of the same power-of-2 alignment.
Previously we always needed nr_entries = mapping_size / 128MB.
Link: https://lists.01.org/pipermail/linux-nvdimm/2016-August/006666.html
Link: http://lkml.kernel.org/r/150215410565.39310.13767886055248249438.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wei Yang [Wed, 6 Sep 2017 23:24:09 +0000 (16:24 -0700)]
mm/vmalloc.c: halve the number of comparisons performed in pcpu_get_vm_areas()
In pcpu_get_vm_areas(), it checks each range is not overlapped. To make
sure it is, only (N^2)/2 comparison is necessary, while current code
does N^2 times. By starting from the next range, it achieves the goal
and the continue could be removed.
Also,
- the overlap check of two ranges could be done with one clause
- one typo in comment is fixed.
Link: http://lkml.kernel.org/r/20170803063822.48702-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wen Yang [Wed, 6 Sep 2017 23:24:06 +0000 (16:24 -0700)]
mm/vmstat: fix divide error at __fragmentation_index
When order is -1 or too big, *1UL << order* will be 0, which will cause
a divide error. Although it seems that all callers of
__fragmentation_index() will only do so with a valid order, the patch
can make it more robust.
Should prevent reoccurrences of
https://bugzilla.kernel.org/show_bug.cgi?id=196555
Link: http://lkml.kernel.org/r/1501751520-2598-1-git-send-email-wen.yang99@zte.com.cn
Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Wed, 6 Sep 2017 23:24:03 +0000 (16:24 -0700)]
mm, hugetlb: do not allocate non-migrateable gigantic pages from movable zones
alloc_gigantic_page doesn't consider movability of the gigantic hugetlb
when scanning eligible ranges for the allocation. As 1GB hugetlb pages
are not movable currently this can break the movable zone assumption
that all allocations are migrateable and as such break memory hotplug.
Reorganize the code and use the standard zonelist allocations scheme
that we use for standard hugetbl pages. htlb_alloc_mask will ensure
that only migratable hugetlb pages will ever see a movable zone.
Link: http://lkml.kernel.org/r/20170803083549.21407-1-mhocko@kernel.org
Fixes:
944d9fec8d7a ("hugetlb: add support for gigantic page allocation at runtime")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrea Arcangeli [Wed, 6 Sep 2017 23:23:59 +0000 (16:23 -0700)]
userfaultfd: provide pid in userfault msg - add feat union
No ABI change, but this will make it more explicit to software that ptid
is only available if requested by passing UFFD_FEATURE_THREAD_ID to
UFFDIO_API. The fact it's a union will also self document it shouldn't
be taken for granted there's a tpid there.
Link: http://lkml.kernel.org/r/20170802165145.22628-7-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Alexey Perevalov <a.perevalov@samsung.com>
Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexey Perevalov [Wed, 6 Sep 2017 23:23:56 +0000 (16:23 -0700)]
userfaultfd: provide pid in userfault msg
It could be useful for calculating downtime during postcopy live
migration per vCPU. Side observer or application itself will be
informed about proper task's sleep during userfaultfd processing.
Process's thread id is being provided when user requeste it by setting
UFFD_FEATURE_THREAD_ID bit into uffdio_api.features.
Link: http://lkml.kernel.org/r/20170802165145.22628-6-aarcange@redhat.com
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrea Arcangeli [Wed, 6 Sep 2017 23:23:53 +0000 (16:23 -0700)]
userfaultfd: call userfaultfd_unmap_prep only if __split_vma succeeds
A __split_vma is not a worthy event to report, and it's definitely not a
unmap so it would be incorrect to report unmap for the whole region to
the userfaultfd manager if a __split_vma fails.
So only call userfaultfd_unmap_prep after the __vma_splitting is over
and do_munmap cannot fail anymore.
Also add unlikely because it's better to optimize for the vast majority
of apps that aren't using userfaultfd in a non cooperative way. Ideally
we should also find a way to eliminate the branch entirely if
CONFIG_USERFAULTFD=n, but it would complicate things so stick to
unlikely for now.
Link: http://lkml.kernel.org/r/20170802165145.22628-5-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Alexey Perevalov <a.perevalov@samsung.com>
Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrea Arcangeli [Wed, 6 Sep 2017 23:23:49 +0000 (16:23 -0700)]
userfaultfd: selftest: explicit failure if the SIGBUS test failed
Showing zero in the output isn't very self explanatory as a successful
result. Show a more explicit error output if the test fails.
Link: http://lkml.kernel.org/r/20170802165145.22628-4-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Alexey Perevalov <a.perevalov@samsung.com>
Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrea Arcangeli [Wed, 6 Sep 2017 23:23:46 +0000 (16:23 -0700)]
userfaultfd: selftest: exercise UFFDIO_COPY/ZEROPAGE -EEXIST
This will retry the UFFDIO_COPY/ZEROPAGE to verify it returns -EEXIST at
the first invocation and then later every 10 seconds.
In the filebacked MAP_SHARED case this also verifies the -EEXIST
triggered in the filesystem pagecache insertion, if the offset in the
file was not a hole.
shmem MAP_SHARED tries to index the newly allocated pagecache in the
radix tree before checking the pagetable so it doesn't need any
assistance to exercise that case.
hugetlbfs checks the pmd to be not none before trying to index the
hugetlbfs page in the radix tree, so it requires to run UFFDIO_COPY into
an alias mapping (the alternative would be to use MADV_DONTNEED to only
zap the pagetables, but that doesn't work on hugetlbfs).
[akpm@linux-foundation.org: fix uffdio_zeropage(), per Mike Kravetz]
Link: http://lkml.kernel.org/r/20170802165145.22628-3-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Alexey Perevalov <a.perevalov@samsung.com>
Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Prakash Sangappa [Wed, 6 Sep 2017 23:23:43 +0000 (16:23 -0700)]
userfaultfd: selftest: add tests for UFFD_FEATURE_SIGBUS feature
Add tests for UFFD_FEATURE_SIGBUS feature. The tests will verify signal
delivery instead of userfault events. Also, test use of UFFDIO_COPY to
allocate memory and retry accessing monitored area after signal
delivery.
Also fix a bug in uffd_poll_thread() where 'uffd' is leaked.
Link: http://lkml.kernel.org/r/1501552446-748335-3-git-send-email-prakash.sangappa@oracle.com
Signed-off-by: Prakash Sangappa <prakash.sangappa@oracle.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Prakash Sangappa [Wed, 6 Sep 2017 23:23:39 +0000 (16:23 -0700)]
mm: userfaultfd: add feature to request for a signal delivery
In some cases, userfaultfd mechanism should just deliver a SIGBUS signal
to the faulting process, instead of the page-fault event. Dealing with
page-fault event using a monitor thread can be an overhead in these
cases. For example applications like the database could use the
signaling mechanism for robustness purpose.
Database uses hugetlbfs for performance reason. Files on hugetlbfs
filesystem are created and huge pages allocated using fallocate() API.
Pages are deallocated/freed using fallocate() hole punching support.
These files are mmapped and accessed by many processes as shared memory.
The database keeps track of which offsets in the hugetlbfs file have
pages allocated.
Any access to mapped address over holes in the file, which can occur due
to bugs in the application, is considered invalid and expect the process
to simply receive a SIGBUS. However, currently when a hole in the file
is accessed via the mapped address, kernel/mm attempts to automatically
allocate a page at page fault time, resulting in implicitly filling the
hole in the file. This may not be the desired behavior for applications
like the database that want to explicitly manage page allocations of
hugetlbfs files.
Using userfaultfd mechanism with this support to get a signal, database
application can prevent pages from being allocated implicitly when
processes access mapped address over holes in the file.
This patch adds UFFD_FEATURE_SIGBUS feature to userfaultfd mechnism to
request for a SIGBUS signal.
See following for previous discussion about the database requirement
leading to this proposal as suggested by Andrea.
http://www.spinics.net/lists/linux-mm/msg129224.html
Link: http://lkml.kernel.org/r/1501552446-748335-2-git-send-email-prakash.sangappa@oracle.com
Signed-off-by: Prakash Sangappa <prakash.sangappa@oracle.com>
Reviewed-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>