KVM: nSVM: Track whether changes in L0 require MSR bitmap for L2 to be rebuilt

Similar to nVMX commit ed2a4800ae9d ("KVM: nVMX: Track whether changes in
L0 require MSR bitmap for L2 to be rebuilt"), introduce a flag to keep
track of whether MSR bitmap for L2 needs to be rebuilt due to changes in
MSR bitmap for L1 or switching to a different L2.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20220202095100.129834-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Add an option to disable MANUAL_PROTECT_ENABLE and INITIALLY_SET

Add an option to dirty_log_perf_test.c to disable
KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE and KVM_DIRTY_LOG_INITIALLY_SET so
the legacy dirty logging code path can be tested.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-19-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Add tracepoint for splitting huge pages

Add a tracepoint that records whenever KVM eagerly splits a huge page
and the error status of the split to indicate if it succeeded or failed
and why.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-18-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Split huge pages mapped by the TDP MMU during KVM_CLEAR_DIRTY_LOG

When using KVM_DIRTY_LOG_INITIALLY_SET, huge pages are not
write-protected when dirty logging is enabled on the memslot. Instead
they are write-protected once userspace invokes KVM_CLEAR_DIRTY_LOG for
the first time and only for the specific sub-region being cleared.

Enhance KVM_CLEAR_DIRTY_LOG to also try to split huge pages prior to
write-protecting to avoid causing write-protection faults on vCPU
threads. This also allows userspace to smear the cost of huge page
splitting across multiple ioctls, rather than splitting the entire
memslot as is the case when initially-all-set is not used.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-17-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Split huge pages mapped by the TDP MMU when dirty logging is enabled

When dirty logging is enabled without initially-all-set, try to split
all huge pages in the memslot down to 4KB pages so that vCPUs do not
have to take expensive write-protection faults to split huge pages.

Eager page splitting is best-effort only. This commit only adds the
support for the TDP MMU, and even there splitting may fail due to out
of memory conditions. Failures to split a huge page is fine from a
correctness standpoint because KVM will always follow up splitting by
write-protecting any remaining huge pages.

Eager page splitting moves the cost of splitting huge pages off of the
vCPU threads and onto the thread enabling dirty logging on the memslot.
This is useful because:

 1. Splitting on the vCPU thread interrupts vCPUs execution and is
    disruptive to customers whereas splitting on VM ioctl threads can
    run in parallel with vCPU execution.

 2. Splitting all huge pages at once is more efficient because it does
    not require performing VM-exit handling or walking the page table for
    every 4KiB page in the memslot, and greatly reduces the amount of
    contention on the mmu_lock.

For example, when running dirty_log_perf_test with 96 virtual CPUs, 1GiB
per vCPU, and 1GiB HugeTLB memory, the time it takes vCPUs to write to
all of their memory after dirty logging is enabled decreased by 95% from
2.94s to 0.14s.

Eager Page Splitting is over 100x more efficient than the current
implementation of splitting on fault under the read lock. For example,
taking the same workload as above, Eager Page Splitting reduced the CPU
required to split all huge pages from ~270 CPU-seconds ((2.94s - 0.14s)
* 96 vCPU threads) to only 1.55 CPU-seconds.

Eager page splitting does increase the amount of time it takes to enable
dirty logging since it has split all huge pages. For example, the time
it took to enable dirty logging in the 96GiB region of the
aforementioned test increased from 0.001s to 1.55s.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-16-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Separate TDP MMU shadow page allocation and initialization

Separate the allocation of shadow pages from their initialization.  This
is in preparation for splitting huge pages outside of the vCPU fault
context, which requires a different allocation mechanism.

No functional changed intended.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-15-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Derive page role for TDP MMU shadow pages from parent

Derive the page role from the parent shadow page, since the only thing
that changes is the level. This is in preparation for splitting huge
pages during VM-ioctls which do not have access to the vCPU MMU context.

No functional change intended.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-14-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Remove redundant role overrides for TDP MMU shadow pages

The vCPU's mmu_role already has the correct values for direct,
has_4_byte_gpte, access, and ad_disabled. Remove the code that was
redundantly overwriting these fields with the same values.

No functional change intended.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-13-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Refactor TDP MMU iterators to take kvm_mmu_page root

Instead of passing a pointer to the root page table and the root level
separately, pass in a pointer to the root kvm_mmu_page struct.  This
reduces the number of arguments by 1, cutting down on line lengths.

No functional change intended.

Reviewed-by: Ben Gardon <bgardon@google.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-12-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Move restore_acc_track_spte() to spte.h

restore_acc_track_spte() is pure SPTE bit manipulation, making it a good
fit for spte.h. And now that the WARN_ON_ONCE() calls have been removed,
there isn't any good reason to not inline it.

This move also prepares for a follow-up commit that will need to call
restore_acc_track_spte() from spte.c

No functional change intended.

Reviewed-by: Ben Gardon <bgardon@google.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-11-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Drop new_spte local variable from restore_acc_track_spte()

The new_spte local variable is unnecessary. Deleting it can save a line
of code and simplify the remaining lines a bit.

No functional change intended.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-10-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Remove unnecessary warnings from restore_acc_track_spte()

The warnings in restore_acc_track_spte() can be removed because the only
caller checks is_access_track_spte(), and is_access_track_spte() checks
!spte_ad_enabled(). In other words, the warning can never be triggered.

No functional change intended.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-9-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Consolidate logic to atomically install a new TDP MMU page table

Consolidate the logic to atomically replace an SPTE with an SPTE that
points to a new page table into a single helper function. This will be
used in a follow-up commit to split huge pages, which involves replacing
each huge page SPTE with an SPTE that points to a page table.

Opportunistically drop the call to trace_kvm_mmu_get_page() in
kvm_tdp_mmu_map() since it is redundant with the identical tracepoint in
tdp_mmu_alloc_sp().

No functional change intended.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-8-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Rename handle_removed_tdp_mmu_page() to handle_removed_pt()

First remove tdp_mmu_ from the name since it is redundant given that it
is a static function in tdp_mmu.c. There is a pattern of using tdp_mmu_
as a prefix in the names of static TDP MMU functions, but all of the
other handle_*() variants do not include such a prefix. So drop it
entirely.

Then change "page" to "pt" to convey that this is operating on a page
table rather than an struct page. Purposely use "pt" instead of "sp"
since this function takes the raw RCU-protected page table pointer as an
argument rather than  a pointer to the struct kvm_mmu_page.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-7-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Rename TDP MMU functions that handle shadow pages

Rename 3 functions in tdp_mmu.c that handle shadow pages:

  alloc_tdp_mmu_page()  -> tdp_mmu_alloc_sp()
  tdp_mmu_link_page()   -> tdp_mmu_link_sp()
  tdp_mmu_unlink_page() -> tdp_mmu_unlink_sp()

These changed make tdp_mmu a consistent prefix before the verb in the
function name, and make it more clear that these functions deal with
kvm_mmu_page structs rather than struct pages.

One could argue that "shadow page" is the wrong term for a page table in
the TDP MMU since it never actually shadows a guest page table.
However, "shadow page" (or "sp" for short) has evolved to become the
standard term in KVM when referring to a kvm_mmu_page struct, and its
associated page table and other metadata, regardless of whether the page
table shadows a guest page table. So this commit just makes the TDP MMU
more consistent with the rest of KVM.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-6-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Change tdp_mmu_{set,zap}_spte_atomic() to return 0/-EBUSY

tdp_mmu_set_spte_atomic() and tdp_mmu_zap_spte_atomic() return a bool
with true indicating the SPTE modification was successful and false
indicating failure. Change these functions to return an int instead
since that is the common practice.

Opportunistically fix up the kernel-doc style for the Return section
above tdp_mmu_set_spte_atomic().

No functional change intended.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-5-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Automatically update iter->old_spte if cmpxchg fails

Consolidate a bunch of code that was manually re-reading the spte if the
cmpxchg failed. There is no extra cost of doing this because we already
have the spte value as a result of the cmpxchg (and in fact this
eliminates re-reading the spte), and none of the call sites depend on
iter->old_spte retaining the stale spte value.

Reviewed-by: Ben Gardon <bgardon@google.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-4-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Rename __rmap_write_protect() to rmap_write_protect()

The function formerly known as rmap_write_protect() has been renamed to
kvm_vcpu_write_protect_gfn(), so we can get rid of the double
underscores in front of __rmap_write_protect().

No functional change intended.

Reviewed-by: Ben Gardon <bgardon@google.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-3-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Rename rmap_write_protect() to kvm_vcpu_write_protect_gfn()

rmap_write_protect() is a poor name because it also write-protects SPTEs
in the TDP MMU, not just SPTEs in the rmap. It is also confusing that
rmap_write_protect() is not a simple wrapper around
__rmap_write_protect(), since that is the common pattern for functions
with double-underscore names.

Rename rmap_write_protect() to kvm_vcpu_write_protect_gfn() to convey
that KVM is write-protecting a specific gfn in the context of a vCPU.

No functional change intended.

Reviewed-by: Ben Gardon <bgardon@google.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220119230739.2234394-2-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Add checks for reserved-to-zero Hyper-V hypercall fields

Add checks for the three fields in Hyper-V's hypercall params that must
be zero.  Per the TLFS, HV_STATUS_INVALID_HYPERCALL_INPUT is returned if
"A reserved bit in the specified hypercall input value is non-zero."

Note, some versions of the TLFS have an off-by-one bug for the last
reserved field, and define it as being bits 64:60.  See
https://github.com/MicrosoftDocs/Virtualization-Documentation/pull/1682.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211207220926.718794-9-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Reject fixeds-size Hyper-V hypercalls with non-zero "var_cnt"

Reject Hyper-V hypercalls if the guest specifies a non-zero variable size
header (var_cnt in KVM) for a hypercall that has a fixed header size.
Per the TLFS:

  It is illegal to specify a non-zero variable header size for a
  hypercall that is not explicitly documented as accepting variable sized
  input headers. In such a case the hypercall will result in a return
  code of HV_STATUS_INVALID_HYPERCALL_INPUT.

Note, at least some of the various DEBUG commands likely aren't allowed
to use variable size headers, but the TLFS documentation doesn't clearly
state what is/isn't allowed.  Omit them for now to avoid unnecessary
breakage.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211207220926.718794-8-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Shove vp_bitmap handling down into sparse_set_to_vcpu_mask()

Move the vp_bitmap "allocation" that's needed to handle mismatched vp_index
values down into sparse_set_to_vcpu_mask() and drop __always_inline from
said helper.  The need for an intermediate vp_bitmap is a detail that's
specific to the sparse translation with mismatched VP<=>vCPU indexes and
does not need to be exposed to the caller.

Regarding the __always_inline, prior to commit f21dd494506a ("KVM: x86:
hyperv: optimize sparse VP set processing") the helper, then named
hv_vcpu_in_sparse_set(), was a tiny bit of code that effectively boiled
down to a handful of bit ops.  The __always_inline was understandable, if
not justifiable.  Since the aforementioned change, sparse_set_to_vcpu_mask()
is a chunky 350-450+ bytes of code without KASAN=y, and balloons to 1100+
with KASAN=y.  In other words, it has no business being forcefully inlined.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211207220926.718794-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Don't bother reading sparse banks that end up being ignored

When handling "sparse" VP_SET requests, don't read sparse banks that
can't possibly contain a legal VP index instead of ignoring such banks
later on in sparse_set_to_vcpu_mask().  This allows KVM to cap the size
of its sparse_banks arrays for VP_SET at KVM_HV_MAX_SPARSE_VCPU_SET_BITS.
Add a compile time assert that KVM_HV_MAX_SPARSE_VCPU_SET_BITS<=64, i.e.
that KVM_MAX_VCPUS<=4096, as the TLFS allows for at most 64 sparse banks,
and KVM will need to do _something_ to play nice with Hyper-V.

Reducing the size of sparse_banks fudges around a compilation warning
(that becomes error with KVM_WERROR=y) when CONFIG_KASAN_STACK=y, which
is selected (and can't be unselected) by CONFIG_KASAN=y when using gcc
(clang/LLVM is a stack hog in some cases so it's opt-in for clang).
KASAN_STACK adds a redzone around every stack variable, which pushes the
Hyper-V functions over the default limit of 1024.

Ideally, KVM would flat out reject such impossibilities, but the TLFS
explicitly allows providing empty banks, even if a bank can't possibly
contain a valid VP index due to its position exceeding KVM's max.

  Furthermore, for a bit 1 in ValidBankMask, it is valid state for the
  corresponding element in BanksContents can be all 0s, meaning no
  processors are specified in this bank.

Arguably KVM should reject and not ignore the "extra" banks, but that can
be done independently and without bloating sparse_banks, e.g. by reading
each "extra" 8-byte chunk individually.

Reported-by: Ajay Garg <ajaygargnsit@gmail.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211207220926.718794-6-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Add a helper to get the sparse VP_SET for IPIs and TLB flushes

Add a helper, kvm_get_sparse_vp_set(), to handle sanity checks related to
the VARHEAD field and reading the sparse banks of a VP_SET.  A future
commit to reduce the memory footprint of sparse_banks will introduce more
common code to the sparse bank retrieval.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211207220926.718794-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Refactor kvm_hv_flush_tlb() to reduce indentation

Refactor the "extended" path of kvm_hv_flush_tlb() to reduce the nesting
depth for the non-fast sparse path, and to make the code more similar to
the extended path in kvm_hv_send_ipi().

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211207220926.718794-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Get the number of Hyper-V sparse banks from the VARHEAD field

Get the number of sparse banks from the VARHEAD field, which the guest is
required to provide as "The size of a variable header, in QWORDS.", where
the variable header is:

  Variable Header Bytes = {Total Header Bytes - sizeof(Fixed Header)}
                          rounded up to nearest multiple of 8
  Variable HeaderSize = Variable Header Bytes / 8

In other words, the VARHEAD should match the number of sparse banks.
Keep the manual count as a sanity check, but otherwise rely on the field
so as to more closely align with the logic defined in the TLFS and to
allow for future cleanups.

Tweak the tracepoint output to use "rep_cnt" instead of simply "cnt" now
that there is also "var_cnt".

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211207220926.718794-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Consolidate comments about {Host,MMU}-writable

Consolidate the large comment above DEFAULT_SPTE_HOST_WRITABLE with the
large comment above is_writable_pte() into one comment. This comment
explains the different reasons why an SPTE may be non-writable and KVM
keeps track of that with the {Host,MMU}-writable bits.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220125230723.1701061-1-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Rename DEFAULT_SPTE_MMU_WRITEABLE to DEFAULT_SPTE_MMU_WRITABLE

Both "writeable" and "writable" are valid, but we should be consistent
about which we use. DEFAULT_SPTE_MMU_WRITEABLE was the odd one out in
the SPTE code, so rename it to DEFAULT_SPTE_MMU_WRITABLE.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220125230713.1700406-1-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Move is_writable_pte() to spte.h

Move is_writable_pte() close to the other functions that check
writability information about SPTEs. While here opportunistically
replace the open-coded bit arithmetic in
check_spte_writable_invariants() with a call to is_writable_pte().

No functional change intended.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220125230518.1697048-4-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Check SPTE writable invariants when setting leaf SPTEs

Check SPTE writable invariants when setting SPTEs rather than in
spte_can_locklessly_be_made_writable(). By the time KVM checks
spte_can_locklessly_be_made_writable(), the SPTE has long been since
corrupted.

Note that these invariants only apply to shadow-present leaf SPTEs (i.e.
not to MMIO SPTEs, non-leaf SPTEs, etc.). Add a comment explaining the
restriction and only instrument the code paths that set shadow-present
leaf SPTEs.

To account for access tracking, also check the SPTE writable invariants
when marking an SPTE as an access track SPTE. This also lets us remove
a redundant WARN from mark_spte_for_access_track().

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220125230518.1697048-3-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Move SPTE writable invariant checks to a helper function

Move the WARNs in spte_can_locklessly_be_made_writable() to a separate
helper function. This is in preparation for moving these checks to the
places where SPTEs are set.

Opportunistically add warning error messages that include the SPTE to
make future debugging of these warnings easier.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220125230518.1697048-2-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: LAPIC: Enable timer posted-interrupt only when mwait/hlt is advertised

As commit 0c5f81dad46 ("KVM: LAPIC: Inject timer interrupt via posted
interrupt") mentioned that the host admin should well tune the guest
setup, so that vCPUs are placed on isolated pCPUs, and with several pCPUs
surplus for *busy* housekeeping.  In this setup, it is preferrable to
disable mwait/hlt/pause vmexits to keep the vCPUs in non-root mode.

However, if only some guests isolated and others not, they would not
have any benefit from posted timer interrupts, and at the same time lose
VMX preemption timer fast paths because kvm_can_post_timer_interrupt()
returns true and therefore forces kvm_can_use_hv_timer() to false.

By guaranteeing that posted-interrupt timer is only used if MWAIT or
HLT are done without vmexit, KVM can make a better choice and use the
VMX preemption timer and the corresponding fast paths.

Reported-by: Aili Yao <yaoaili@kingsoft.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Cc: Aili Yao <yaoaili@kingsoft.com>
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1643112538-36743-1-git-send-email-wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: VMX: Dont' send posted IRQ if vCPU == this vCPU and vCPU is IN_GUEST_MODE

When delivering a virtual interrupt, don't actually send a posted interrupt
if the target vCPU is also the currently running vCPU and is IN_GUEST_MODE,
in which case the interrupt is being sent from a VM-Exit fastpath and the
core run loop in vcpu_enter_guest() will manually move the interrupt from
the PIR to vmcs.GUEST_RVI.  IRQs are disabled while IN_GUEST_MODE, thus
there's no possibility of the virtual interrupt being sent from anything
other than KVM, i.e. KVM won't suppress a wake event from an IRQ handler
(see commit fdba608f15e2, "KVM: VMX: Wake vCPU when delivering posted IRQ
even if vCPU == this vCPU").

Eliding the posted interrupt restores the performance provided by the
combination of commits 379a3c8ee444 ("KVM: VMX: Optimize posted-interrupt
delivery for timer fastpath") and 26efe2fd92e5 ("KVM: VMX: Handle
preemption timer fastpath").

Thanks Sean for better comments.

Suggested-by: Chao Gao <chao.gao@intel.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1643111979-36447-1-git-send-email-wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: SVM: Rename hook implementations to conform to kvm_x86_ops' names

Massage SVM's implementation names that still diverge from kvm_x86_ops to
allow for wiring up all SVM-defined functions via kvm-x86-ops.h.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-22-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: SVM: Rename SEV implemenations to conform to kvm_x86_ops hooks

Rename svm_vm_copy_asid_from() and svm_vm_migrate_from() to conform to
the names used by kvm_x86_ops, and opportunistically use "sev" instead of
"svm" to more precisely identify the role of the hooks.

svm_vm_copy_asid_from() in particular was poorly named as the function
does much more than simply copy the ASID.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-21-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Use more verbose names for mem encrypt kvm_x86_ops hooks

Use slightly more verbose names for the so called "memory encrypt",
a.k.a. "mem enc", kvm_x86_ops hooks to bridge the gap between the current
super short kvm_x86_ops names and SVM's more verbose, but non-conforming
names.  This is a step toward using kvm-x86-ops.h with KVM_X86_CVM_OP()
to fill svm_x86_ops.

Opportunistically rename mem_enc_op() to mem_enc_ioctl() to better
reflect its true nature, as it really is a full fledged ioctl() of its
own.  Ideally, the hook would be named confidential_vm_ioctl() or so, as
the ioctl() is a gateway to more than just memory encryption, and because
its underlying purpose to support Confidential VMs, which can be provided
without memory encryption, e.g. if the TCB of the guest includes the host
kernel but not host userspace, or by isolation in hardware without
encrypting memory.  But, diverging from KVM_MEMORY_ENCRYPT_OP even
further is undeseriable, and short of creating alises for all related
ioctl()s, which introduces a different flavor of divergence, KVM is stuck
with the nomenclature.

Defer renaming SVM's functions to a future commit as there are additional
changes needed to make SVM fully conforming and to match reality (looking
at you, svm_vm_copy_asid_from()).

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-20-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: SVM: Remove unused MAX_INST_SIZE #define

Remove SVM's MAX_INST_SIZE, which has long since been obsoleted by the
common MAX_INSN_SIZE.  Note, the latter's "insn" is also the generally
preferred abbreviation of instruction.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-18-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: SVM: Rename svm_flush_tlb() to svm_flush_tlb_current()

Rename svm_flush_tlb() to svm_flush_tlb_current() so that at least one of
the flushing operations in svm_x86_ops can be filled via kvm-x86-ops.h,
and to document the scope of the flush (specifically that it doesn't
flush "all").

Opportunistically make svm_tlb_flush_current(), was svm_flush_tlb(),
static.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-17-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Move get_cs_db_l_bits() helper to SVM

Move kvm_get_cs_db_l_bits() to SVM and rename it appropriately so that
its svm_x86_ops entry can be filled via kvm-x86-ops, and to eliminate a
superfluous export from KVM x86.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-16-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: VMX: Rename VMX functions to conform to kvm_x86_ops names

Massage VMX's implementation names for kvm_x86_ops to maximize use of
kvm-x86-ops.h.  Leave cpu_has_vmx_wbinvd_exit() as-is to preserve the
cpu_has_vmx_*() pattern used for querying VMCS capabilities.  Keep
pi_has_pending_interrupt() as vmx_dy_apicv_has_pending_interrupt() does
a poor job of describing exactly what is being checked in VMX land.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-14-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Use static_call() for copy/move encryption context ioctls()

Define and use static_call()s for .vm_{copy,move}_enc_context_from(),
mostly so that the op is defined in kvm-x86-ops.h.  This will allow using
KVM_X86_OP in vendor code to wire up the implementation.  Any performance
gains eeked out by using static_call() is a happy bonus and not the
primary motiviation.

Opportunistically refactor the code to reduce indentation and keep line
lengths reasonable, and to be consistent when wrapping versus running
a bit over the 80 char soft limit.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-12-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Unexport kvm_x86_ops

Drop the export of kvm_x86_ops now it is no longer referenced by SVM or
VMX.  Disallowing access to kvm_x86_ops is very desirable as it prevents
vendor code from incorrectly modifying hooks after they have been set by
kvm_arch_hardware_setup(), and more importantly after each function's
associated static_call key has been updated.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-11-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Uninline and export hv_track_root_tdp()

Uninline and export Hyper-V's hv_track_root_tdp(), which is (somewhat
indirectly) the last remaining reference to kvm_x86_ops from vendor
modules, i.e. will allow unexporting kvm_x86_ops.  Reloading the TDP PGD
isn't the fastest of paths, hv_track_root_tdp() isn't exactly tiny, and
disallowing vendor code from accessing kvm_x86_ops provides nice-to-have
encapsulation of common x86 code (and of Hyper-V code for that matter).

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-10-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: nVMX: Refactor PMU refresh to avoid referencing kvm_x86_ops.pmu_ops

Refactor the nested VMX PMU refresh helper to pass it a flag stating
whether or not the vCPU has PERF_GLOBAL_CTRL instead of having the nVMX
helper query the information by bouncing through kvm_x86_ops.pmu_ops.
This will allow a future patch to use static_call() for the PMU ops
without having to export any static call definitions from common x86, and
it is also a step toward unexported kvm_x86_ops.

Alternatively, nVMX could call kvm_pmu_is_valid_msr() to indirectly use
kvm_x86_ops.pmu_ops, but that would incur an extra layer of indirection
and would require exporting kvm_pmu_is_valid_msr().

Opportunistically rename the helper to keep line lengths somewhat
reasonable, and to better capture its high-level role.

No functional change intended.

Cc: Like Xu <like.xu.linux@gmail.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-9-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: xen: Use static_call() for invoking kvm_x86_ops hooks

Use static_call() for invoking kvm_x86_ops function that already have a
defined static call, mostly as a step toward having _all_ calls to
kvm_x86_ops route through a static_call() in order to simplify auditing,
e.g. via grep, that all functions have an entry in kvm-x86-ops.h, but
also because there's no reason not to use a static_call().

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-8-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Use static_call() for .vcpu_deliver_sipi_vector()

Define and use a static_call() for kvm_x86_ops.vcpu_deliver_sipi_vector(),
mostly so that the op is defined in kvm-x86-ops.h.  This will allow using
KVM_X86_OP in vendor code to wire up the implementation.  Any performance
gains eeked out by using static_call() is a happy bonus and not the
primary motiviation.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-6-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: VMX: Call vmx_get_cpl() directly in handle_dr()

Use vmx_get_cpl() instead of bouncing through kvm_x86_ops.get_cpl() when
performing a CPL check on MOV DR accesses.  This avoids a RETPOLINE (when
enabled), and more importantly removes a vendor reference to kvm_x86_ops
and helps pave the way for unexporting kvm_x86_ops.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Rename kvm_x86_ops pointers to align w/ preferred vendor names

Rename a variety of kvm_x86_op function pointers so that preferred name
for vendor implementations follows the pattern <vendor>_<function>, e.g.
rename .run() to .vcpu_run() to match {svm,vmx}_vcpu_run().  This will
allow vendor implementations to be wired up via the KVM_X86_OP macro.

In many cases, VMX and SVM "disagree" on the preferred name, though in
reality it's VMX and x86 that disagree as SVM blindly prepended _svm to
the kvm_x86_ops name.  Justification for using the VMX nomenclature:

  - set_{irq,nmi} => inject_{irq,nmi} because the helper is injecting an
    event that has already been "set" in e.g. the vIRR.  SVM's relevant
    VMCB field is even named event_inj, and KVM's stat is irq_injections.

  - prepare_guest_switch => prepare_switch_to_guest because the former is
    ambiguous, e.g. it could mean switching between multiple guests,
    switching from the guest to host, etc...

  - update_pi_irte => pi_update_irte to allow for matching match the rest
    of VMX's posted interrupt naming scheme, which is vmx_pi_<blah>().

  - start_assignment => pi_start_assignment to again follow VMX's posted
    interrupt naming scheme, and to provide context for what bit of code
    might care about an otherwise undescribed "assignment".

The "tlb_flush" => "flush_tlb" creates an inconsistency with respect to
Hyper-V's "tlb_remote_flush" hooks, but Hyper-V really is the one that's
wrong.  x86, VMX, and SVM all use flush_tlb, and even common KVM is on a
variant of the bandwagon with "kvm_flush_remote_tlbs", e.g. a more
appropriate name for the Hyper-V hooks would be flush_remote_tlbs.  Leave
that change for another time as the Hyper-V hooks always start as NULL,
i.e. the name doesn't matter for using kvm-x86-ops.h, and changing all
names requires an astounding amount of churn.

VMX and SVM function names are intentionally left as is to minimize the
diff.  Both VMX and SVM will need to rename even more functions in order
to fully utilize KVM_X86_OPS, i.e. an additional patch for each is
inevitable.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Drop export for .tlb_flush_current() static_call key

Remove the export of kvm_x86_tlb_flush_current() as there are no longer
any users outside of common x86 code.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: skip host CPUID call for hypervisor leaves

Hypervisor leaves are always synthesized by __do_cpuid_func; just return
zeroes and do not ask the host.  Even on nested virtualization, a value
from another hypervisor would be bogus, because all hypercalls and MSRs
are processed by KVM.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Remove unused "flags" of kvm_pv_kick_cpu_op()

The "unsigned long flags" parameter of  kvm_pv_kick_cpu_op() is not used,
so remove it. No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-20-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: Remove unused "kvm" of kvm_make_vcpu_request()

The "struct kvm *kvm" parameter of kvm_make_vcpu_request() is not used,
so remove it. No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-19-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Remove unused "vcpu" of kvm_scale_tsc()

The "struct kvm_vcpu *vcpu" parameter of kvm_scale_tsc() is not used,
so remove it. No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-18-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/emulate: Remove unused "tss_selector" of task_switch_{16, 32}()

The "u16 tss_selector" parameter of task_switch_{16, 32}()
is not used, so remove it. No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-16-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/emulate: Remove unused "ctxt" of setup_syscalls_segments()

The "struct x86_emulate_ctxt *ctxt" parameter of setup_syscalls_segments()
is not used, so remove it. No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-15-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/ioapic: Remove unused "addr" and "length" of ioapic_read_indirect()

The "unsigned long addr" and "unsigned long length" parameter of
ioapic_read_indirect() is not used, so remove it.

No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-14-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/i8259: Remove unused "addr" of elcr_ioport_{read,write}()

The "u32 addr" parameter of elcr_ioport_write() and elcr_ioport_read()
is not used, so remove it. No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-13-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: SVM: improve split between svm_prepare_guest_switch and sev_es_prepare_guest_switch

KVM performs the VMSAVE to the host save area for both regular and SEV-ES
guests, so hoist it up to svm_prepare_guest_switch.  And because
sev_es_prepare_guest_switch does not really need to know the details
of struct svm_cpu_data *, just pass it the pointer to the host save area
inside the HSAVE page.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/svm: Remove unused "vcpu" of svm_check_exit_valid()

The "struct kvm_vcpu *vcpu" parameter of svm_check_exit_valid()
is not used, so remove it. No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-7-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu_audit: Remove unused "level" of audit_spte_after_sync()

The "int level" parameter of audit_spte_after_sync() is not used,
so remove it. No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-6-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/tdp_mmu: Remove unused "kvm" of kvm_tdp_mmu_get_root()

The "struct kvm *kvm" parameter of kvm_tdp_mmu_get_root() is not used,
so remove it. No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-5-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Remove unused "vcpu" of reset_{tdp,ept}_shadow_zero_bits_mask()

The "struct kvm_vcpu *vcpu" parameter of reset_ept_shadow_zero_bits_mask()
and reset_tdp_shadow_zero_bits_mask() is not used, so remove it.

No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-4-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Remove unused "kvm" of __rmap_write_protect()

The "struct kvm *kvm" parameter of __rmap_write_protect()
is not used, so remove it. No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-3-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Remove unused "kvm" of kvm_mmu_unlink_parents()

The "struct kvm *kvm" parameter of kvm_mmu_unlink_parents()
is not used, so remove it. No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-2-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Skip APICv update if APICv is disable at the module level

Bail from the APICv update paths _before_ taking apicv_update_lock if
APICv is disabled at the module level.  kvm_request_apicv_update() in
particular is invoked from multiple paths that can be reached without
APICv being enabled, e.g. svm_enable_irq_window(), and taking the
rw_sem for write when APICv is disabled may introduce unnecessary
contention and stalls.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211208015236.1616697-25-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Drop NULL check on kvm_x86_ops.check_apicv_inhibit_reasons

Drop the useless NULL check on kvm_x86_ops.check_apicv_inhibit_reasons
when handling an APICv update, both VMX and SVM unconditionally implement
the helper and leave it non-NULL even if APICv is disabled at the module
level.  The latter is a moot point now that __kvm_request_apicv_update()
is called if and only if enable_apicv is true.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211208015236.1616697-26-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Unexport __kvm_request_apicv_update()

Unexport __kvm_request_apicv_update(), it's not used by vendor code and
should never be used by vendor code.  The only reason it's exposed at all
is because Hyper-V's SynIC needs to track how many auto-EOIs are in use,
and it's convenient to use apicv_update_lock to guard that tracking.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211208015236.1616697-27-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Zap _all_ roots when unmapping gfn range in TDP MMU

Zap both valid and invalid roots when zapping/unmapping a gfn range, as
KVM must ensure it holds no references to the freed page after returning
from the unmap operation.  Most notably, the TDP MMU doesn't zap invalid
roots in mmu_notifier callbacks.  This leads to use-after-free and other
issues if the mmu_notifier runs to completion while an invalid root
zapper yields as KVM fails to honor the requirement that there must be
_no_ references to the page after the mmu_notifier returns.

The bug is most easily reproduced by hacking KVM to cause a collision
between set_nx_huge_pages() and kvm_mmu_notifier_release(), but the bug
exists between kvm_mmu_notifier_invalidate_range_start() and memslot
updates as well.  Invalidating a root ensures pages aren't accessible by
the guest, and KVM won't read or write page data itself, but KVM will
trigger e.g. kvm_set_pfn_dirty() when zapping SPTEs, and thus completing
a zap of an invalid root _after_ the mmu_notifier returns is fatal.

  WARNING: CPU: 24 PID: 1496 at arch/x86/kvm/../../../virt/kvm/kvm_main.c:173 [kvm]
  RIP: 0010:kvm_is_zone_device_pfn+0x96/0xa0 [kvm]
  Call Trace:
   <TASK>
   kvm_set_pfn_dirty+0xa8/0xe0 [kvm]
   __handle_changed_spte+0x2ab/0x5e0 [kvm]
   __handle_changed_spte+0x2ab/0x5e0 [kvm]
   __handle_changed_spte+0x2ab/0x5e0 [kvm]
   zap_gfn_range+0x1f3/0x310 [kvm]
   kvm_tdp_mmu_zap_invalidated_roots+0x50/0x90 [kvm]
   kvm_mmu_zap_all_fast+0x177/0x1a0 [kvm]
   set_nx_huge_pages+0xb4/0x190 [kvm]
   param_attr_store+0x70/0x100
   module_attr_store+0x19/0x30
   kernfs_fop_write_iter+0x119/0x1b0
   new_sync_write+0x11c/0x1b0
   vfs_write+0x1cc/0x270
   ksys_write+0x5f/0xe0
   do_syscall_64+0x38/0xc0
   entry_SYSCALL_64_after_hwframe+0x44/0xae
   </TASK>

Fixes: b7cccd397f31 ("KVM: x86/mmu: Fast invalidation for TDP MMU")
Cc: stable@vger.kernel.org
Cc: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211215011557.399940-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Move "invalid" check out of kvm_tdp_mmu_get_root()

Move the check for an invalid root out of kvm_tdp_mmu_get_root() and into
the one place it actually matters, tdp_mmu_next_root(), as the other user
already has an implicit validity check.  A future bug fix will need to
get references to invalid roots to honor mmu_notifier requests; there's
no point in forcing what will be a common path to open code getting a
reference to a root.

No functional change intended.

Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211215011557.399940-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Use common TDP MMU zap helper for MMU notifier unmap hook

Use the common TDP MMU zap helper when handling an MMU notifier unmap
event, the two flows are semantically identical.  Consolidate the code in
preparation for a future bug fix, as both kvm_tdp_mmu_unmap_gfn_range()
and __kvm_tdp_mmu_zap_gfn_range() are guilty of not zapping SPTEs in
invalid roots.

No functional change intended.

Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211215011557.399940-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/xen: Fix runstate updates to be atomic when preempting vCPU

There are circumstances whem kvm_xen_update_runstate_guest() should not
sleep because it ends up being called from __schedule() when the vCPU
is preempted:

[  222.830825]  kvm_xen_update_runstate_guest+0x24/0x100
[  222.830878]  kvm_arch_vcpu_put+0x14c/0x200
[  222.830920]  kvm_sched_out+0x30/0x40
[  222.830960]  __schedule+0x55c/0x9f0

To handle this, make it use the same trick as __kvm_xen_has_interrupt(),
of using the hva from the gfn_to_hva_cache directly. Then it can use
pagefault_disable() around the accesses and just bail out if the page
is absent (which is unlikely).

I almost switched to using a gfn_to_pfn_cache here and bailing out if
kvm_map_gfn() fails, like kvm_steal_time_set_preempted() does — but on
closer inspection it looks like kvm_map_gfn() will *always* fail in
atomic context for a page in IOMEM, which means it will silently fail
to make the update every single time for such guests, AFAICT. So I
didn't do it that way after all. And will probably fix that one too.

Cc: stable@vger.kernel.org
Fixes: 30b5c851af79 ("KVM: x86/xen: Add support for vCPU runstate information")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <b17a93e5ff4561e57b1238e3e7ccd0b613eb827e.camel@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: SVM: move avic definitions from AMD's spec to svm.h

asm/svm.h is the correct place for all values that are defined in
the SVM spec, and that includes AVIC.

Also add some values from the spec that were not defined before
and will be soon useful.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220207155447.840194-10-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: lapic: don't touch irr_pending in kvm_apic_update_apicv when inhibiting it

kvm_apic_update_apicv is called when AVIC is still active, thus IRR bits
can be set by the CPU after it is called, and don't cause the irr_pending
to be set to true.

Also logic in avic_kick_target_vcpu doesn't expect a race with this
function so to make it simple, just keep irr_pending set to true and
let the next interrupt injection to the guest clear it.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220207155447.840194-9-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: nSVM: deal with L1 hypervisor that intercepts interrupts but lets L2 control them

Fix a corner case in which the L1 hypervisor intercepts
interrupts (INTERCEPT_INTR) and either doesn't set
virtual interrupt masking (V_INTR_MASKING) or enters a
nested guest with EFLAGS.IF disabled prior to the entry.

In this case, despite the fact that L1 intercepts the interrupts,
KVM still needs to set up an interrupt window to wait before
injecting the INTR vmexit.

Currently the KVM instead enters an endless loop of 'req_immediate_exit'.

Exactly the same issue also happens for SMIs and NMI.
Fix this as well.

Note that on VMX, this case is impossible as there is only
'vmexit on external interrupts' execution control which either set,
in which case both host and guest's EFLAGS.IF
are ignored, or not set, in which case no VMexits are delivered.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220207155447.840194-8-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: nSVM: expose clean bit support to the guest

KVM already honours few clean bits thus it makes sense
to let the nested guest know about it.

Note that KVM also doesn't check if the hardware supports
clean bits, and therefore nested KVM was
already setting clean bits and L0 KVM
was already honouring them.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220207155447.840194-6-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: nSVM/nVMX: set nested_run_pending on VM entry which is a result of RSM

While RSM induced VM entries are not full VM entries,
they still need to be followed by actual VM entry to complete it,
unlike setting the nested state.

This patch fixes boot of hyperv and SMM enabled
windows VM running nested on KVM, which fail due
to this issue combined with lack of dirty bit setting.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Cc: stable@vger.kernel.org
Message-Id: <20220207155447.840194-5-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: nSVM: mark vmcb01 as dirty when restoring SMM saved state

While usually, restoring the smm state makes the KVM enter
the nested guest thus a different vmcb (vmcb02 vs vmcb01),
KVM should still mark it as dirty, since hardware
can in theory cache multiple vmcbs.

Failure to do so, combined with lack of setting the
nested_run_pending (which is fixed in the next patch),
might make KVM re-enter vmcb01, which was just exited from,
with completely different set of guest state registers
(SMM vs non SMM) and without proper dirty bits set,
which results in the CPU reusing stale IDTR pointer
which leads to a guest shutdown on any interrupt.

On the real hardware this usually doesn't happen,
but when running nested, L0's KVM does check and
honour few dirty bits, causing this issue to happen.

This patch fixes boot of hyperv and SMM enabled
windows VM running nested on KVM.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Cc: stable@vger.kernel.org
Message-Id: <20220207155447.840194-4-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: nSVM: fix potential NULL derefernce on nested migration

Turns out that due to review feedback and/or rebases
I accidentally moved the call to nested_svm_load_cr3 to be too early,
before the NPT is enabled, which is very wrong to do.

KVM can't even access guest memory at that point as nested NPT
is needed for that, and of course it won't initialize the walk_mmu,
which is main issue the patch was addressing.

Fix this for real.

Fixes: 232f75d3b4b5 ("KVM: nSVM: call nested_svm_load_cr3 on nested state load")
Cc: stable@vger.kernel.org
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220207155447.840194-3-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: SVM: don't passthrough SMAP/SMEP/PKE bits in !NPT && !gCR0.PG case

When the guest doesn't enable paging, and NPT/EPT is disabled, we
use guest't paging CR3's as KVM's shadow paging pointer and
we are technically in direct mode as if we were to use NPT/EPT.

In direct mode we create SPTEs with user mode permissions
because usually in the direct mode the NPT/EPT doesn't
need to restrict access based on guest CPL
(there are MBE/GMET extenstions for that but KVM doesn't use them).

In this special "use guest paging as direct" mode however,
and if CR4.SMAP/CR4.SMEP are enabled, that will make the CPU
fault on each access and KVM will enter endless loop of page faults.

Since page protection doesn't have any meaning in !PG case,
just don't passthrough these bits.

The fix is the same as was done for VMX in commit:
commit 656ec4a4928a ("KVM: VMX: fix SMEP and SMAP without EPT")

This fixes the boot of windows 10 without NPT for good.
(Without this patch, BSP boots, but APs were stuck in endless
loop of page faults, causing the VM boot with 1 CPU)

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Cc: stable@vger.kernel.org
Message-Id: <20220207155447.840194-2-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Revert "svm: Add warning message for AVIC IPI invalid target"

Remove a WARN on an "AVIC IPI invalid target" exit, the WARN is trivial
to trigger from guest as it will fail on any destination APIC ID that
doesn't exist from the guest's perspective.

Don't bother recording anything in the kernel log, the common tracepoint
for kvm_avic_incomplete_ipi() is sufficient for debugging.

This reverts commit 37ef0c4414c9743ba7f1af4392f0a27a99649f2a.

Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220204214205.3306634-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Linux 5.17-rc3

Merge tag 'ext4_for_linus_stable' of git://git./linux/kernel/git/tytso/ext4

Pull ext4 fixes from Ted Ts'o:
 "Various bug fixes for ext4 fast commit and inline data handling.

  Also fix regression introduced as part of moving to the new mount API"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  fs/ext4: fix comments mentioning i_mutex
  ext4: fix incorrect type issue during replay_del_range
  jbd2: fix kernel-doc descriptions for jbd2_journal_shrink_{scan,count}()
  ext4: fix potential NULL pointer dereference in ext4_fill_super()
  jbd2: refactor wait logic for transaction updates into a common function
  jbd2: cleanup unused functions declarations from jbd2.h
  ext4: fix error handling in ext4_fc_record_modified_inode()
  ext4: remove redundant max inline_size check in ext4_da_write_inline_data_begin()
  ext4: fix error handling in ext4_restore_inline_data()
  ext4: fast commit may miss file actions
  ext4: fast commit may not fallback for ineligible commit
  ext4: modify the logic of ext4_mb_new_blocks_simple
  ext4: prevent used blocks from being allocated during fast commit replay

Merge tag 'perf-tools-fixes-for-v5.17-2022-02-06' of git://git./linux/kernel/git/acme/linux

Pull perf tools fixes from Arnaldo Carvalho de Melo:

 - Fix display of grouped aliased events in 'perf stat'.

 - Add missing branch_sample_type to perf_event_attr__fprintf().

 - Apply correct label to user/kernel symbols in branch mode.

 - Fix 'perf ftrace' system_wide tracing, it has to be set before
   creating the maps.

 - Return error if procfs isn't mounted for PID namespaces when
   synthesizing records for pre-existing processes.

 - Set error stream of objdump process for 'perf annotate' TUI, to avoid
   garbling the screen.

 - Add missing arm64 support to perf_mmap__read_self(), the kernel part
   got into 5.17.

 - Check for NULL pointer before dereference writing debug info about a
   sample.

 - Update UAPI copies for asound, perf_event, prctl and kvm headers.

 - Fix a typo in bpf_counter_cgroup.c.

* tag 'perf-tools-fixes-for-v5.17-2022-02-06' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
  perf ftrace: system_wide collection is not effective by default
  libperf: Add arm64 support to perf_mmap__read_self()
  tools include UAPI: Sync sound/asound.h copy with the kernel sources
  perf stat: Fix display of grouped aliased events
  perf tools: Apply correct label to user/kernel symbols in branch mode
  perf bpf: Fix a typo in bpf_counter_cgroup.c
  perf synthetic-events: Return error if procfs isn't mounted for PID namespaces
  perf session: Check for NULL pointer before dereference
  perf annotate: Set error stream of objdump process for TUI
  perf tools: Add missing branch_sample_type to perf_event_attr__fprintf()
  tools headers UAPI: Sync linux/kvm.h with the kernel sources
  tools headers UAPI: Sync linux/prctl.h with the kernel sources
  perf beauty: Make the prctl arg regexp more strict to cope with PR_SET_VMA
  tools headers cpufeatures: Sync with the kernel sources
  tools headers UAPI: Sync linux/perf_event.h with the kernel sources
  tools include UAPI: Sync sound/asound.h copy with the kernel sources

Merge tag 'perf_urgent_for_v5.17_rc3' of git://git./linux/kernel/git/tip/tip

Pull perf fixes from Borislav Petkov:

 - Intel/PT: filters could crash the kernel

 - Intel: default disable the PMU for SMM, some new-ish EFI firmware has
   started using CPL3 and the PMU CPL filters don't discriminate against
   SMM, meaning that CPL3 (userspace only) events now also count EFI/SMM
   cycles.

 - Fixup for perf_event_attr::sig_data

* tag 'perf_urgent_for_v5.17_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/pt: Fix crash with stop filters in single-range mode
  perf: uapi: Document perf_event_attr::sig_data truncation on 32 bit architectures
  selftests/perf_events: Test modification of perf_event_attr::sig_data
  perf: Copy perf_event_attr::sig_data on modification
  x86/perf: Default set FREEZE_ON_SMI for all

Merge tag 'objtool_urgent_for_v5.17_rc3' of git://git./linux/kernel/git/tip/tip

Pull objtool fix from Borislav Petkov:
 "Fix a potential truncated string warning triggered by gcc12"

* tag 'objtool_urgent_for_v5.17_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Fix truncated string warning

Merge tag 'irq_urgent_for_v5.17_rc3' of git://git./linux/kernel/git/tip/tip

Pull irq fix from Borislav Petkov:
 "Remove a bogus warning introduced by the recent PCI MSI irq affinity
  overhaul"

* tag 'irq_urgent_for_v5.17_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  PCI/MSI: Remove bogus warning in pci_irq_get_affinity()

Merge tag 'edac_urgent_for_v5.17_rc3' of git://git./linux/kernel/git/ras/ras

Pull EDAC fixes from Borislav Petkov:
 "Fix altera and xgene EDAC drivers to propagate the correct error code
  from platform_get_irq() so that deferred probing still works"

* tag 'edac_urgent_for_v5.17_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
  EDAC/xgene: Fix deferred probing
  EDAC/altera: Fix deferred probing

perf ftrace: system_wide collection is not effective by default

The ftrace.target.system_wide must be set before invoking
evlist__create_maps(), otherwise it has no effect.

Fixes: 53be50282269b46c ("perf ftrace: Add 'latency' subcommand")
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Acked-by: Namhyung Kim <namhyung@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220127132010.4836-1-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

libperf: Add arm64 support to perf_mmap__read_self()

Add the arm64 variants for read_perf_counter() and read_timestamp().
Unfortunately the counter number is encoded into the instruction, so the
code is a bit verbose to enumerate all possible counters.

Tested-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: https://lore.kernel.org/r/20220201214056.702854-1-robh@kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-perf-users@vger.kernel.org

tools include UAPI: Sync sound/asound.h copy with the kernel sources

Picking the changes from:

  06feec6005c9d950 ("ASoC: hdmi-codec: Fix OOB memory accesses")

Which entails no changes in the tooling side as it doesn't introduce new
SNDRV_PCM_IOCTL_ ioctls.

To silence this perf tools build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/sound/asound.h' differs from latest version at 'include/uapi/sound/asound.h'
  diff -u tools/include/uapi/sound/asound.h include/uapi/sound/asound.h

Cc: Dmitry Osipenko <digetx@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/lkml/Yf+6OT+2eMrYDEeX@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf stat: Fix display of grouped aliased events

An event may have a number of uncore aliases that when added to the
evlist are consecutive.

If there are multiple uncore events in a group then
parse_events__set_leader_for_uncore_aliase will reorder the evlist so
that events on the same PMU are adjacent.

The collect_all_aliases function assumes that aliases are in blocks so
that only the first counter is printed and all others are marked merged.

The reordering for groups breaks the assumption and so all counts are
printed.

This change removes the assumption from collect_all_aliases
that the events are in blocks and instead processes the entire evlist.

Before:

  ```
  $ perf stat -e '{UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE,UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE},duration_time' -a -A -- sleep 1

   Performance counter stats for 'system wide':

  CPU0                  256,866      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 494,413      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                      967      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,738      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  285,161      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 429,920      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                      955      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,443      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  310,753      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 416,657      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,231      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,573      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  416,067      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 405,966      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,481      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,447      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  312,911      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 408,154      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,086      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,380      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  333,994      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 370,349      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,287      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,335      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  188,107      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 302,423      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                      701      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,070      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  307,221      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 383,642      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,036      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,158      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  318,479      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 821,545      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,028      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   2,550      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  227,618      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 372,272      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                      903      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,456      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  376,783      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 419,827      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,406      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,453      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  286,583      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 429,956      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                      999      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,436      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  313,867      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 370,159      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,114      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,291      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  342,083      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 409,111      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,399      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,684      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  365,828      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 376,037      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,378      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,411      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  382,456      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 621,743      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,232      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,955      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  342,316      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 385,067      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,176      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,268      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  373,588      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 386,163      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,394      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,464      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  381,206      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 546,891      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,266      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,712      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  221,176      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 392,069      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                      831      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,456      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  355,401      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 705,595      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,235      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   2,216      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  371,436      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 428,103      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,306      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,442      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  384,352      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 504,200      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,468      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,860      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  228,856      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 287,976      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                      832      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,060      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  215,121      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 334,162      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                      681      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,026      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  296,179      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 436,083      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,084      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,525      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  262,296      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 416,573      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                      986      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,533      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  285,852      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 359,842      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,073      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,326      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  303,379      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 367,222      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,008      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,156      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  273,487      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 425,449      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                      932      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,367      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  297,596      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 414,793      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,140      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,601      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  342,365      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 360,422      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,291      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,342      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  327,196      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 580,858      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,122      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   2,014      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  296,564      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 452,817      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,087      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,694      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  375,002      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 389,393      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,478      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   1,540      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0                  365,213      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36                 594,685      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                    1,401      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                   2,222      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0            1,000,749,060 ns   duration_time

         1.000749060 seconds time elapsed
  ```

After:

  ```
   Performance counter stats for 'system wide':

  CPU0               20,547,434      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU36              45,202,862      UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE
  CPU0                   82,001      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU36                 159,688      UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE
  CPU0            1,000,464,828 ns   duration_time

         1.000464828 seconds time elapsed
  ```

Fixes: 3cdc5c2cb924acb4 ("perf parse-events: Handle uncore event aliases in small groups properly")
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: Asaf Yaffe <asaf.yaffe@intel.com>
Cc: Caleb Biggers <caleb.biggers@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kshipra Bopardikar <kshipra.bopardikar@intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Perry Taylor <perry.taylor@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vineet Singh <vineet.singh@intel.com>
Cc: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Link: https://lore.kernel.org/r/20220205010941.1065469-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Apply correct label to user/kernel symbols in branch mode

In branch mode, the branch symbols were being displayed with incorrect
cpumode labels. So fix this.

For example, before:
  # perf record -b -a -- sleep 1
  # perf report -b

  Overhead  Command  Source Shared Object  Source Symbol               Target Symbol
     0.08%  swapper  [kernel.kallsyms]     [k] rcu_idle_enter          [k] cpuidle_enter_state
 ==> 0.08%  cmd0     [kernel.kallsyms]     [.] psi_group_change        [.] psi_group_change
     0.08%  cmd1     [kernel.kallsyms]     [k] psi_group_change        [k] psi_group_change

After:
  # perf report -b

  Overhead  Command  Source Shared Object  Source Symbol               Target Symbol
     0.08%  swapper  [kernel.kallsyms]     [k] rcu_idle_enter          [k] cpuidle_enter_state
     0.08%  cmd0     [kernel.kallsyms]     [k] psi_group_change        [k] pei_group_change
     0.08%  cmd1     [kernel.kallsyms]     [k] psi_group_change        [k] psi_group_change

Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: German Gomez <german.gomez@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20220126105927.3411216-1-german.gomez@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf: Fix a typo in bpf_counter_cgroup.c

This patch fixes a spelling typo in error message.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20211225005558.503935-1-standby24x7@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf synthetic-events: Return error if procfs isn't mounted for PID namespaces

For perf recording, it retrieves process info by iterating nodes in proc
fs.  If we run perf in a non-root PID namespace with command:

  # unshare --fork --pid perf record -e cycles -a -- test_program

... in this case, unshare command creates a child PID namespace and
launches perf tool in it, but the issue is the proc fs is not mounted
for the non-root PID namespace, this leads to the perf tool gathering
process info from its parent PID namespace.

We can use below command to observe the process nodes under proc fs:

  # unshare --pid --fork ls /proc
1    137   1968  2128  3    342  48  62   78      crypto   kcore        net       uptime
10   138   2  2142  30   35  49  63   8      devices   keys        pagetypeinfo   version
11   139   20  2143  304  36  50  64   82      device-tree  key-users    partitions     vmallocinfo
12   14    2011  22    305  37  51  65   83      diskstats   kmsg        self       vmstat
128  140   2038  23    307  39  52  656  84      driver   kpagecgroup  slabinfo       zoneinfo
129  15    2074  24    309  4  53  67   9      execdomains  kpagecount   softirqs
13   16    2094  241   31   40  54  68   asound     fb   kpageflags   stat
130  164   2096  242   310  41  55  69   buddyinfo  filesystems  loadavg      swaps
131  17    2098  25    317  42  56  70   bus      fs   locks        sys
132  175   21  26    32   43  57  71   cgroups    interrupts   meminfo      sysrq-trigger
133  179   2102  263   329  44  58  75   cmdline    iomem   misc        sysvipc
134  1875  2103  27    330  45  59  76   config.gz  ioports   modules      thread-self
135  19    2117  29    333  46  6   77   consoles   irq   mounts       timer_list
136  1941  2121  298   34   47  60  773  cpuinfo    kallsyms   mtd        tty

So it shows many existed tasks, since unshared command has not mounted
the proc fs for the new created PID namespace, it still accesses the
proc fs of the root PID namespace.  This leads to two prominent issues:

- Firstly, PID values are mismatched between thread info and samples.
  The gathered thread info are coming from the proc fs of the root PID
  namespace, but samples record its PID from the child PID namespace.

- The second issue is profiled program 'test_program' returns its forked
  PID number from the child PID namespace, perf tool wrongly uses this
  PID number to retrieve the process info via the proc fs of the root
  PID namespace.

To avoid issues, we need to mount proc fs for the child PID namespace
with the option '--mount-proc' when use unshare command:

  # unshare --fork --pid --mount-proc perf record -e cycles -a -- test_program

Conversely, when the proc fs of the root PID namespace is used by child
namespace, perf tool can detect the multiple PID levels and
nsinfo__is_in_root_namespace() returns false, this patch reports error
for this case:

  # unshare --fork --pid perf record -e cycles -a -- test_program
  Couldn't synthesize bpf events.
  Perf runs in non-root PID namespace but it tries to gather process info from its parent PID namespace.
  Please mount the proc file system properly, e.g. add the option '--mount-proc' for unshare command.

Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20211224124014.2492751-1-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf session: Check for NULL pointer before dereference

Move NULL pointer check before dereferencing the variable.

Addresses-Coverity: 1497622 ("Derereference before null check")
Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Ameer Hamza <amhamza.mgc@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Link: https://lore.kernel.org/r/20220125121141.18347-1-amhamza.mgc@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf annotate: Set error stream of objdump process for TUI

The stderr should be set to a pipe when using TUI.  Otherwise it'd
print to stdout and break TUI windows with an error message.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20220202070828.143303-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Add missing branch_sample_type to perf_event_attr__fprintf()

This updates branch sample type with missing PERF_SAMPLE_BRANCH_TYPE_SAVE.

Suggested-by: James Clark <james.clark@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/1643799443-15109-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools headers UAPI: Sync linux/kvm.h with the kernel sources

To pick the changes in:

  f6c6804c43fa18d3 ("kvm: Move KVM_GET_XSAVE2 IOCTL definition at the end of kvm.h")

That just rebuilds perf, as these patches don't add any new KVM ioctl to
be harvested for the the 'perf trace' ioctl syscall argument
beautifiers.

This is also by now used by tools/testing/selftests/kvm/, a simple test
build succeeded.

This silences this perf build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/kvm.h' differs from latest version at 'include/uapi/linux/kvm.h'
  diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h

Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Link: http://lore.kernel.org/lkml/Yf+4k5Fs5Q3HdSG9@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge remote-tracking branch 'torvalds/master' into perf/urgent

To check if more kernel API sync is needed and also to see if the perf
build tests continue to pass.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge tag 'for-linus-5.17a-rc3-tag' of git://git./linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:

 - documentation fixes related to Xen

 - enable x2apic mode when available when running as hardware
   virtualized guest under Xen

 - cleanup and fix a corner case of vcpu enumeration when running a
   paravirtualized Xen guest

* tag 'for-linus-5.17a-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/Xen: streamline (and fix) PV CPU enumeration
  xen: update missing ioctl magic numers documentation
  Improve docs for IOCTL_GNTDEV_MAP_GRANT_REF
  xen: xenbus_dev.h: delete incorrect file name
  xen/x2apic: enable x2apic mode when supported for HVM