Dan Carpenter [Tue, 8 Apr 2014 23:04:19 +0000 (16:04 -0700)]
fs/ncpfs/dir.c: fix indenting in ncp_lookup()
My static checker suggests adding curly braces here. Probably that was
the intent, but actually the code works the same either way. I've just
changed the indenting and left the code as-is.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Petr Vandrovec <petr@vandrovec.name>
Acked-by: Dave Chiluk <chiluk@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Tue, 8 Apr 2014 23:04:18 +0000 (16:04 -0700)]
ncpfs/inode.c: fix mismatch printk formats and arguments
Conversions to ncp_dbg showed some format/argument mismatches so fix
them.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Tue, 8 Apr 2014 23:04:17 +0000 (16:04 -0700)]
ncpfs: remove now unused PRINTK macro
Uses are gone, remove the macro.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Tue, 8 Apr 2014 23:04:16 +0000 (16:04 -0700)]
ncpfs: convert PPRINTK to ncp_vdbg
Use a more current logging style.
Convert the paranoia debug statement to vdbg.
Remove the embedded function names as dynamic_debug can do that.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Tue, 8 Apr 2014 23:04:15 +0000 (16:04 -0700)]
ncpfs: convert DPRINTK/DDPRINTK to ncp_dbg
Use a more current logging style and enable use of dynamic debugging.
Remove embedded function names, dynamic debug can add this instead.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Tue, 8 Apr 2014 23:04:14 +0000 (16:04 -0700)]
ncpfs: Add pr_fmt and convert printks to pr_<level>
Convert to a more current logging style.
Add pr_fmt to prefix with "ncpfs: ".
Remove the embedded function names and use "%s: ", __func__
Some previously unprefixed messages now have "ncpfs: "
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Tue, 8 Apr 2014 23:04:13 +0000 (16:04 -0700)]
arch/x86/mm/kmemcheck/kmemcheck.c: use kstrtoint() instead of sscanf()
Kmemcheck should use the preferred interface for parsing command line
arguments, kstrto*(), rather than sscanf() itself. Use it
appropriately.
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Acked-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jens Axboe [Tue, 8 Apr 2014 23:04:12 +0000 (16:04 -0700)]
lib/percpu_counter.c: fix bad percpu counter state during suspend
I got a bug report yesterday from Laszlo Ersek in which he states that
his kvm instance fails to suspend. Laszlo bisected it down to this
commit
1cf7e9c68fe8 ("virtio_blk: blk-mq support") where virtio-blk is
converted to use the blk-mq infrastructure.
After digging a bit, it became clear that the issue was with the queue
drain. blk-mq tracks queue usage in a percpu counter, which is
incremented on request alloc and decremented when the request is freed.
The initial hunt was for an inconsistency in blk-mq, but everything
seemed fine. In fact, the counter only returned crazy values when
suspend was in progress.
When a CPU is unplugged, the percpu counters merges that CPU state with
the general state. blk-mq takes care to register a hotcpu notifier with
the appropriate priority, so we know it runs after the percpu counter
notifier. However, the percpu counter notifier only merges the state
when the CPU is fully gone. This leaves a state transition where the
CPU going away is no longer in the online mask, yet it still holds
private values. This means that in this state, percpu_counter_sum()
returns invalid results, and the suspend then hangs waiting for
abs(dead-cpu-value) requests to complete which of course will never
happen.
Fix this by clearing the state earlier, so we never have a case where
the CPU isn't in online mask but still holds private state. This bug
has been there since forever, I guess we don't have a lot of users where
percpu counters needs to be reliable during the suspend cycle.
Signed-off-by: Jens Axboe <axboe@fb.com>
Reported-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sasha Levin [Tue, 8 Apr 2014 23:04:11 +0000 (16:04 -0700)]
autofs4: check dev ioctl size before allocating
There wasn't any check of the size passed from userspace before trying
to allocate the memory required.
This meant that userspace might request more space than allowed,
triggering an OOM.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Tue, 8 Apr 2014 23:04:10 +0000 (16:04 -0700)]
mm: vmscan: do not swap anon pages just because free+file is low
Page reclaim force-scans / swaps anonymous pages when file cache drops
below the high watermark of a zone in order to prevent what little cache
remains from thrashing.
However, on bigger machines the high watermark value can be quite large
and when the workload is dominated by a static anonymous/shmem set, the
file set might just be a small window of used-once cache. In such
situations, the VM starts swapping heavily when instead it should be
recycling the no longer used cache.
This is a longer-standing problem, but it's more likely to trigger after
commit
81c0a2bb515f ("mm: page_alloc: fair zone allocator policy")
because file pages can no longer accumulate in a single zone and are
dispersed into smaller fractions among the available zones.
To resolve this, do not force scan anon when file pages are low but
instead rely on the scan/rotation ratios to make the right prediction.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Rafael Aquini <aquini@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Suleiman Souhlal <suleiman@google.com>
Cc: <stable@kernel.org> [3.12+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Tue, 8 Apr 2014 16:52:16 +0000 (09:52 -0700)]
Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
Pull drm updates from Dave Airlie:
"Highlights:
- drm:
Generic display port aux features, primary plane support, drm
master management fixes, logging cleanups, enforced locking checks
(instead of docs), documentation improvements, minor number
handling cleanup, pseudofs for shared inodes.
- ttm:
add ability to allocate from both ends
- i915:
broadwell features, power domain and runtime pm, per-process
address space infrastructure (not enabled)
- msm:
power management, hdmi audio support
- nouveau:
ongoing GPU fault recovery, initial maxwell support, random fixes
- exynos:
refactored driver to clean up a lot of abstraction, DP support
moved into drm, LVDS bridge support added, parallel panel support
- gma500:
SGX MMU support, SGX irq handling, asle irq work fixes
- radeon:
video engine bringup, ring handling fixes, use dp aux helpers
- vmwgfx:
add rendernode support"
* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (849 commits)
DRM: armada: fix corruption while loading cursors
drm/dp_helper: don't return EPROTO for defers (v2)
drm/bridge: export ptn3460_init function
drm/exynos: remove MODULE_DEVICE_TABLE definitions
ARM: dts: exynos4412-trats2: enable exynos/fimd node
ARM: dts: exynos4210-trats: enable exynos/fimd node
ARM: dts: exynos4412-trats2: add panel node
ARM: dts: exynos4210-trats: add panel node
ARM: dts: exynos4: add MIPI DSI Master node
drm/panel: add S6E8AA0 driver
ARM: dts: exynos4210-universal_c210: add proper panel node
drm/panel: add ld9040 driver
panel/ld9040: add DT bindings
panel/s6e8aa0: add DT bindings
drm/exynos: add DSIM driver
exynos/dsim: add DT bindings
drm/exynos: disallow fbdev initialization if no device is connected
drm/mipi_dsi: create dsi devices only for nodes with reg property
drm/mipi_dsi: add flags to DSI messages
Skip intel_crt_init for Dell XPS 8700
...
Heiko Carstens [Tue, 8 Apr 2014 10:55:46 +0000 (12:55 +0200)]
include/linux/syscalls.h: add sys_renameat2() prototype
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Tue, 8 Apr 2014 00:59:17 +0000 (17:59 -0700)]
Merge branch 'for_linus' of git://git./linux/kernel/git/jack/linux-fs
Pull ext3 improvements, cleanups, reiserfs fix from Jan Kara:
"various cleanups for ext2, ext3, udf, isofs, a documentation update
for quota, and a fix of a race in reiserfs readdir implementation"
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
reiserfs: fix race in readdir
ext2: acl: remove unneeded include of linux/capability.h
ext3: explicitly remove inode from orphan list after failed direct io
fs/isofs/inode.c add __init to init_inodecache()
ext3: Speedup WB_SYNC_ALL pass
fs/quota/Kconfig: Update filesystems
ext3: Update outdated comment before ext3_ordered_writepage()
ext3: Update PF_MEMALLOC handling in ext3_write_inode()
ext2/3: use prandom_u32() instead of get_random_bytes()
ext3: remove an unneeded check in ext3_new_blocks()
ext3: remove unneeded check in ext3_ordered_writepage()
fs: Mark function as static in ext3/xattr_security.c
fs: Mark function as static in ext3/dir.c
fs: Mark function as static in ext2/xattr_security.c
ext3: Add __init macro to init_inodecache
ext2: Add __init macro to init_inodecache
udf: Add __init macro to init_inodecache
fs: udf: parse_options: blocksize check
Linus Torvalds [Tue, 8 Apr 2014 00:52:31 +0000 (17:52 -0700)]
Merge branch 'kbuild' of git://git./linux/kernel/git/mmarek/kbuild
Pull kbuild changes from Michal Marek:
- cleanups in the main Makefiles and Documentation/DocBook/Makefile
- make O=... directory is automatically created if needed
- mrproper/distclean removes the old include/linux/version.h to make
life easier when bisecting across the commit that moved the version.h
file
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
kbuild: docbook: fix the include error when executing "make help"
kbuild: create a build directory automatically for out-of-tree build
kbuild: remove redundant '.*.cmd' pattern from make distclean
kbuild: move "quote" to Kbuild.include to be consistent
kbuild: docbook: use $(obj) and $(src) rather than specific path
kbuild: unconditionally clobber include/linux/version.h on distclean
kbuild: docbook: specify KERNELDOC dependency correctly
kbuild: docbook: include cmd files more simply
kbuild: specify build_docproc as a phony target
Linus Torvalds [Tue, 8 Apr 2014 00:51:34 +0000 (17:51 -0700)]
Merge tag 'arc-v3.15-rc1' of git://git./linux/kernel/git/vgupta/arc
Pull ARC changes from Vineet Gupta:
- Support for external initrd from Noam
- Fix broken serial console in nsimosci Virtual Platform
- Reuse of ENTRY/END assembler macros across hand asm code
- Other minor fixes here and there
* tag 'arc-v3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: [nsimosci] Unbork console
ARC: [nsimosci] Change .dts to use generic 8250 UART
ARC: [SMP] General Fixes
ARC: Remove unused DT template file
ARC: [clockevent] simplify timer ISR
ARC: [clockevent] can't be SoC specific
ARC: Remove ARC_HAS_COH_RTSC
ARC: switch to generic ENTRY/END assembler annotations
ARC: support external initrd
ARC: add uImage to .gitignore
ARC: [arcfpga] Fix __initconst data const-correctness
Russell King [Mon, 7 Apr 2014 11:00:17 +0000 (12:00 +0100)]
DRM: armada: fix corruption while loading cursors
Loading cursors to the LCD controller's SRAM can be corrupted when the
configured pixel clock is relatively slow. This seems to be caused
when we write back-to-back to the SRAM registers.
There doesn't appear to be any status register we can read to check
when an access has completed.
Inserting a dummy read between the writes appears to fix the problem.
Cc: <stable@vger.kernel.org> # 3.13
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Linus Torvalds [Tue, 8 Apr 2014 00:50:18 +0000 (17:50 -0700)]
Merge tag 'stable/for-linus-3.15-tag2' of git://git./linux/kernel/git/xen/tip
Pull Xen build fix from David Vrabel:
"Fix arm build of drivers/xen/events/
The merge of irq-core-for-linus branch broke it"
* tag 'stable/for-linus-3.15-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
Xen: do hv callback accounting only on x86
Linus Torvalds [Mon, 7 Apr 2014 23:38:06 +0000 (16:38 -0700)]
Merge branch 'akpm' (incoming from Andrew)
Merge second patch-bomb from Andrew Morton:
- the rest of MM
- zram updates
- zswap updates
- exit
- procfs
- exec
- wait
- crash dump
- lib/idr
- rapidio
- adfs, affs, bfs, ufs
- cris
- Kconfig things
- initramfs
- small amount of IPC material
- percpu enhancements
- early ioremap support
- various other misc things
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (156 commits)
MAINTAINERS: update Intel C600 SAS driver maintainers
fs/ufs: remove unused ufs_super_block_third pointer
fs/ufs: remove unused ufs_super_block_second pointer
fs/ufs: remove unused ufs_super_block_first pointer
fs/ufs/super.c: add __init to init_inodecache()
doc/kernel-parameters.txt: add early_ioremap_debug
arm64: add early_ioremap support
arm64: initialize pgprot info earlier in boot
x86: use generic early_ioremap
mm: create generic early_ioremap() support
x86/mm: sparse warning fix for early_memremap
lglock: map to spinlock when !CONFIG_SMP
percpu: add preemption checks to __this_cpu ops
vmstat: use raw_cpu_ops to avoid false positives on preemption checks
slub: use raw_cpu_inc for incrementing statistics
net: replace __this_cpu_inc in route.c with raw_cpu_inc
modules: use raw_cpu_write for initialization of per cpu refcount.
mm: use raw_cpu ops for determining current NUMA node
percpu: add raw_cpu_ops
slub: fix leak of 'name' in sysfs_slab_add
...
Lukasz Dorau [Mon, 7 Apr 2014 22:39:58 +0000 (15:39 -0700)]
MAINTAINERS: update Intel C600 SAS driver maintainers
Signed-off-by: Lukasz Dorau <lukasz.dorau@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
Cc: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christian Engelmayer [Mon, 7 Apr 2014 22:39:57 +0000 (15:39 -0700)]
fs/ufs: remove unused ufs_super_block_third pointer
Pointer 'usb3' to struct ufs_super_block_third acquired via
ubh_get_usb_third() is never used in function
ufs_read_cylinder_structures(). Thus remove it.
Detected by Coverity: CID 139939.
Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christian Engelmayer [Mon, 7 Apr 2014 22:39:57 +0000 (15:39 -0700)]
fs/ufs: remove unused ufs_super_block_second pointer
Pointer 'usb2' to struct ufs_super_block_second acquired via
ubh_get_usb_second() is never used in function ufs_statfs(). Thus
remove it.
Detected by Coverity: CID 139940.
Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christian Engelmayer [Mon, 7 Apr 2014 22:39:56 +0000 (15:39 -0700)]
fs/ufs: remove unused ufs_super_block_first pointer
Remove occurences of unused pointers to struct ufs_super_block_first
that were acquired via ubh_get_usb_first().
Detected by Coverity: CID 139929 - CID 139936, CID 139940.
Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fabian Frederick [Mon, 7 Apr 2014 22:39:55 +0000 (15:39 -0700)]
fs/ufs/super.c: add __init to init_inodecache()
init_inodecache is only called by __init init_ufs_fs.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mark Salter [Mon, 7 Apr 2014 22:39:53 +0000 (15:39 -0700)]
doc/kernel-parameters.txt: add early_ioremap_debug
Add description of early_ioremap_debug kernel parameter.
Signed-off-by: Mark Salter <msalter@redhat.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mark Salter [Mon, 7 Apr 2014 22:39:52 +0000 (15:39 -0700)]
arm64: add early_ioremap support
Add support for early IO or memory mappings which are needed before the
normal ioremap() is usable. This also adds fixmap support for permanent
fixed mappings such as that used by the earlyprintk device register
region.
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mark Salter [Mon, 7 Apr 2014 22:39:51 +0000 (15:39 -0700)]
arm64: initialize pgprot info earlier in boot
Presently, paging_init() calls init_mem_pgprot() to initialize pgprot
values used by macros such as PAGE_KERNEL, PAGE_KERNEL_EXEC, etc.
The new fixmap and early_ioremap support also needs to use these macros
before paging_init() is called. This patch moves the init_mem_pgprot()
call out of paging_init() and into setup_arch() so that pgprot_default
gets initialized in time for fixmap and early_ioremap.
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mark Salter [Mon, 7 Apr 2014 22:39:49 +0000 (15:39 -0700)]
x86: use generic early_ioremap
Move x86 over to the generic early ioremap implementation.
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mark Salter [Mon, 7 Apr 2014 22:39:48 +0000 (15:39 -0700)]
mm: create generic early_ioremap() support
This patch creates a generic implementation of early_ioremap() support
based on the existing x86 implementation. early_ioremp() is useful for
early boot code which needs to temporarily map I/O or memory regions
before normal mapping functions such as ioremap() are available.
Some architectures have optional MMU. In the no-MMU case, the remap
functions simply return the passed in physical address and the unmap
functions do nothing.
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Young [Mon, 7 Apr 2014 22:39:46 +0000 (15:39 -0700)]
x86/mm: sparse warning fix for early_memremap
This patch series takes the common bits from the x86 early ioremap
implementation and creates a generic implementation which may be used by
other architectures. The early ioremap interfaces are intended for
situations where boot code needs to make temporary virtual mappings
before the normal ioremap interfaces are available. Typically, this
means before paging_init() has run.
This patch (of 6):
There's a lot of sparse warnings for code like below: void *a =
early_memremap(phys_addr, size);
early_memremap intend to map kernel memory with ioremap facility, the
return pointer should be a kernel ram pointer instead of iomem one.
For making the function clearer and supressing sparse warnings this patch
do below two things:
1. cast to (__force void *) for the return value of early_memremap
2. add early_memunmap function and pass (__force void __iomem *) to iounmap
From Boris:
"Ingo told me yesterday, it makes sense too. I'd guess we can try it.
FWIW, all callers of early_memremap use the memory they get remapped
as normal memory so we should be safe"
Signed-off-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josh Triplett [Mon, 7 Apr 2014 22:39:45 +0000 (15:39 -0700)]
lglock: map to spinlock when !CONFIG_SMP
When the system has only one CPU, lglock is effectively a spinlock; map
it directly to spinlock to eliminate the indirection and duplicate code.
In addition to removing overhead, this drops 1.6k of code with a
defconfig modified to have !CONFIG_SMP, and 1.1k with a minimal config.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: David Howells <dhowells@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christoph Lameter [Mon, 7 Apr 2014 22:39:44 +0000 (15:39 -0700)]
percpu: add preemption checks to __this_cpu ops
We define a check function in order to avoid trouble with the include
files. Then the higher level __this_cpu macros are modified to invoke
the preemption check.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Christoph Lameter <cl@linux.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Tested-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christoph Lameter [Mon, 7 Apr 2014 22:39:43 +0000 (15:39 -0700)]
vmstat: use raw_cpu_ops to avoid false positives on preemption checks
vm counters are allowed to be racy. Use raw_cpu_ops to avoid the
local_irq_disable overhead and to avoid preemption checks which will be
added to the __this_cpu operations.
[akpm@linux-foundation.org: Add comment. Again.]
Signed-off-by: Christoph Lameter <cl@linux.com>
Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christoph Lameter [Mon, 7 Apr 2014 22:39:42 +0000 (15:39 -0700)]
slub: use raw_cpu_inc for incrementing statistics
Statistics are not critical to the operation of the allocation but
should also not cause too much overhead.
When __this_cpu_inc is altered to check if preemption is disabled this
triggers. Use raw_cpu_inc to avoid the checks. Using this_cpu_ops may
cause interrupt disable/enable sequences on various arches which may
significantly impact allocator performance.
[akpm@linux-foundation.org: add comment]
Signed-off-by: Christoph Lameter <cl@linux.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christoph Lameter [Mon, 7 Apr 2014 22:39:40 +0000 (15:39 -0700)]
net: replace __this_cpu_inc in route.c with raw_cpu_inc
The RT_CACHE_STAT_INC macro triggers the new preemption checks
for __this_cpu ops.
I do not see any other synchronization that would allow the use of a
__this_cpu operation here however in commit
dbd2915ce87e ("[IPV4]:
RT_CACHE_STAT_INC() warning fix") Andrew justifies the use of
raw_smp_processor_id() here because "we do not care" about races. In
the past we agreed that the price of disabling interrupts here to get
consistent counters would be too high. These counters may be inaccurate
due to race conditions.
The use of __this_cpu op improves the situation already from what commit
dbd2915ce87e did since the single instruction emitted on x86 does not
allow the race to occur anymore. However, non x86 platforms could still
experience a race here.
Trace:
__this_cpu_add operation in preemptible [
00000000] code: avahi-daemon/1193
caller is __this_cpu_preempt_check+0x38/0x60
CPU: 1 PID: 1193 Comm: avahi-daemon Tainted: GF 3.12.0-rc4+ #187
Call Trace:
check_preemption_disabled+0xec/0x110
__this_cpu_preempt_check+0x38/0x60
__ip_route_output_key+0x575/0x8c0
ip_route_output_flow+0x27/0x70
udp_sendmsg+0x825/0xa20
inet_sendmsg+0x85/0xc0
sock_sendmsg+0x9c/0xd0
___sys_sendmsg+0x37c/0x390
__sys_sendmsg+0x49/0x90
SyS_sendmsg+0x12/0x20
tracesys+0xe1/0xe6
Signed-off-by: Christoph Lameter <cl@linux.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christoph Lameter [Mon, 7 Apr 2014 22:39:39 +0000 (15:39 -0700)]
modules: use raw_cpu_write for initialization of per cpu refcount.
The initialization of a structure is not subject to synchronization.
The use of __this_cpu would trigger a false positive with the additional
preemption checks for __this_cpu ops.
So simply disable the check through the use of raw_cpu ops.
Trace:
__this_cpu_write operation in preemptible [
00000000] code: modprobe/286
caller is __this_cpu_preempt_check+0x38/0x60
CPU: 3 PID: 286 Comm: modprobe Tainted: GF 3.12.0-rc4+ #187
Call Trace:
dump_stack+0x4e/0x82
check_preemption_disabled+0xec/0x110
__this_cpu_preempt_check+0x38/0x60
load_module+0xcfd/0x2650
SyS_init_module+0xa6/0xd0
tracesys+0xe1/0xe6
Signed-off-by: Christoph Lameter <cl@linux.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christoph Lameter [Mon, 7 Apr 2014 22:39:38 +0000 (15:39 -0700)]
mm: use raw_cpu ops for determining current NUMA node
With the preempt checking logic for __this_cpu_ops we will get false
positives from locations in the code that use numa_node_id.
Before the __this_cpu ops where introduced there were no checks for
preemption present either. smp_raw_processor_id() was used. See
http://www.spinics.net/lists/linux-numa/msg00641.html
Therefore we need to use raw_cpu_read here to avoid false postives.
Note that this issue has been discussed in prior years. If the process
changes nodes after retrieving the current numa node then that is
acceptable since most uses of numa_node etc are for optimization and not
for correctness.
There were suggestions to implement a raw_numa_node_id in order to do
preempt checks for numa_node_id as well. But I think we better defer
that to another patch since that would mean investigating how
numa_node_id() is used throughout the kernel which would increase the
scope of this patchset significantly. After all preemption was never
checked before when numa_node_id() was used.
Some sample traces:
__this_cpu_read operation in preemptible [
00000000] code: login/1456
caller is __this_cpu_preempt_check+0x2b/0x2d
CPU: 0 PID: 1456 Comm: login Not tainted 3.12.0-rc4-cl-00062-g2fe80d3-dirty #185
Call Trace:
dump_stack+0x4e/0x82
check_preemption_disabled+0xc5/0xe0
__this_cpu_preempt_check+0x2b/0x2d
get_task_policy+0x1d/0x49
get_vma_policy+0x14/0x76
alloc_pages_vma+0x35/0xff
handle_mm_fault+0x290/0x73b
__do_page_fault+0x3fe/0x44d
do_page_fault+0x9/0xc
page_fault+0x22/0x30
generic_file_aio_read+0x38e/0x624
do_sync_read+0x54/0x73
vfs_read+0x9d/0x12a
SyS_read+0x47/0x7e
cstar_dispatch+0x7/0x23
caller is __this_cpu_preempt_check+0x2b/0x2d
CPU: 0 PID: 1456 Comm: login Not tainted 3.12.0-rc4-cl-00062-g2fe80d3-dirty #185
Call Trace:
dump_stack+0x4e/0x82
check_preemption_disabled+0xc5/0xe0
__this_cpu_preempt_check+0x2b/0x2d
alloc_pages_current+0x8f/0xbc
__page_cache_alloc+0xb/0xd
__do_page_cache_readahead+0xf4/0x219
ra_submit+0x1c/0x20
ondemand_readahead+0x28c/0x2b4
page_cache_sync_readahead+0x38/0x3a
generic_file_aio_read+0x261/0x624
do_sync_read+0x54/0x73
vfs_read+0x9d/0x12a
SyS_read+0x47/0x7e
cstar_dispatch+0x7/0x23
Signed-off-by: Christoph Lameter <cl@linux.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Alex Shi <alex.shi@intel.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christoph Lameter [Mon, 7 Apr 2014 22:39:34 +0000 (15:39 -0700)]
percpu: add raw_cpu_ops
The kernel has never been audited to ensure that this_cpu operations are
consistently used throughout the kernel. The code generated in many
places can be improved through the use of this_cpu operations (which
uses a segment register for relocation of per cpu offsets instead of
performing address calculations).
The patch set also addresses various consistency issues in general with
the per cpu macros.
A. The semantics of __this_cpu_ptr() differs from this_cpu_ptr only
because checks are skipped. This is typically shown through a raw_
prefix. So this patch set changes the places where __this_cpu_ptr()
is used to raw_cpu_ptr().
B. There has been the long term wish by some that __this_cpu operations
would check for preemption. However, there are cases where preemption
checks need to be skipped. This patch set adds raw_cpu operations that
do not check for preemption and then adds preemption checks to the
__this_cpu operations.
C. The use of __get_cpu_var is always a reference to a percpu variable
that can also be handled via a this_cpu operation. This patch set
replaces all uses of __get_cpu_var with this_cpu operations.
D. We can then use this_cpu RMW operations in various places replacing
sequences of instructions by a single one.
E. The use of this_cpu operations throughout will allow other arches than
x86 to implement optimized references and RMV operations to work with
per cpu local data.
F. The use of this_cpu operations opens up the possibility to
further optimize code that relies on synchronization through
per cpu data.
The patch set works in a couple of stages:
I. Patch 1 adds the additional raw_cpu operations and raw_cpu_ptr().
Also converts the existing __this_cpu_xx_# primitive in the x86
code to raw_cpu_xx_#.
II. Patch 2-4 use the raw_cpu operations in places that would give
us false positives once they are enabled.
III. Patch 5 adds preemption checks to __this_cpu operations to allow
checking if preemption is properly disabled when these functions
are used.
IV. Patches 6-20 are patches that simply replace uses of __get_cpu_var
with this_cpu_ptr. They do not depend on any changes to the percpu
code. No preemption tests are skipped if they are applied.
V. Patches 21-46 are conversion patches that use this_cpu operations
in various kernel subsystems/drivers or arch code.
VI. Patches 47/48 (not included in this series) remove no longer used
functions (__this_cpu_ptr and __get_cpu_var). These should only be
applied after all the conversion patches have made it and after we
have done additional passes through the kernel to ensure that none of
the uses of these functions remain.
This patch (of 46):
The patches following this one will add preemption checks to __this_cpu
ops so we need to have an alternative way to use this_cpu operations
without preemption checks.
raw_cpu_ops will be the basis for all other ops since these will be the
operations that do not implement any checks.
Primitive operations are renamed by this patch from __this_cpu_xxx to
raw_cpu_xxxx.
Also change the uses of the x86 percpu primitives in preempt.h.
These depend directly on asm/percpu.h (header #include nesting issue).
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Alex Shi <alex.shi@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: David Daney <david.daney@cavium.com>
Cc: David Miller <davem@davemloft.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Dipankar Sarma <dipankar@in.ibm.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Hedi Berriche <hedi@sgi.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Mike Travis <travis@sgi.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Robert Richter <rric@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Jones [Mon, 7 Apr 2014 22:39:32 +0000 (15:39 -0700)]
slub: fix leak of 'name' in sysfs_slab_add
The failure paths of sysfs_slab_add don't release the allocation of
'name' made by create_unique_id() a few lines above the context of the
diff below. Create a common exit path to make it more obvious what
needs freeing.
[vdavydov@parallels.com: free the name only if !unmergeable]
Signed-off-by: Dave Jones <davej@fedoraproject.org>
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Mon, 7 Apr 2014 22:39:31 +0000 (15:39 -0700)]
slub: rework sysfs layout for memcg caches
Currently, we try to arrange sysfs entries for memcg caches in the same
manner as for global caches. Apart from turning /sys/kernel/slab into a
mess when there are a lot of kmem-active memcgs created, it actually
does not work properly - we won't create more than one link to a memcg
cache in case its parent is merged with another cache. For instance, if
A is a root cache merged with another root cache B, we will have the
following sysfs setup:
X
A -> X
B -> X
where X is some unique id (see create_unique_id()). Now if memcgs M and
N start to allocate from cache A (or B, which is the same), we will get:
X
X:M
X:N
A -> X
B -> X
A:M -> X:M
A:N -> X:N
Since B is an alias for A, we won't get entries B:M and B:N, which is
confusing.
It is more logical to have entries for memcg caches under the
corresponding root cache's sysfs directory. This would allow us to keep
sysfs layout clean, and avoid such inconsistencies like one described
above.
This patch does the trick. It creates a "cgroup" kset in each root
cache kobject to keep its children caches there.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Glauber Costa <glommer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Mon, 7 Apr 2014 22:39:29 +0000 (15:39 -0700)]
slub: adjust memcg caches when creating cache alias
Otherwise, kzalloc() called from a memcg won't clear the whole object.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Glauber Costa <glommer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Mon, 7 Apr 2014 22:39:28 +0000 (15:39 -0700)]
memcg, slab: do not destroy children caches if parent has aliases
Currently we destroy children caches at the very beginning of
kmem_cache_destroy(). This is wrong, because the root cache will not
necessarily be destroyed in the end - if it has aliases (refcount > 0),
kmem_cache_destroy() will simply decrement its refcount and return. In
this case, at best we will get a bunch of warnings in dmesg, like this
one:
kmem_cache_destroy kmalloc-32:0: Slab cache still has objects
CPU: 1 PID: 7139 Comm: modprobe Tainted: G B W 3.13.0+ #117
Call Trace:
dump_stack+0x49/0x5b
kmem_cache_destroy+0xdf/0xf0
kmem_cache_destroy_memcg_children+0x97/0xc0
kmem_cache_destroy+0xf/0xf0
xfs_mru_cache_uninit+0x21/0x30 [xfs]
exit_xfs_fs+0x2e/0xc44 [xfs]
SyS_delete_module+0x198/0x1f0
system_call_fastpath+0x16/0x1b
At worst - if kmem_cache_destroy() will race with an allocation from a
memcg cache - the kernel will panic.
This patch fixes this by moving children caches destruction after the
check if the cache has aliases. Plus, it forbids destroying a root
cache if it still has children caches, because each children cache keeps
a reference to its parent.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Glauber Costa <glommer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Mon, 7 Apr 2014 22:39:27 +0000 (15:39 -0700)]
memcg, slab: unregister cache from memcg before starting to destroy it
Currently, memcg_unregister_cache(), which deletes the cache being
destroyed from the memcg_slab_caches list, is called after
__kmem_cache_shutdown() (see kmem_cache_destroy()), which starts to
destroy the cache.
As a result, one can access a partially destroyed cache while traversing
a memcg_slab_caches list, which can have deadly consequences (for
instance, cache_show() called for each cache on a memcg_slab_caches list
from mem_cgroup_slabinfo_read() will dereference pointers to already
freed data).
To fix this, let's move memcg_unregister_cache() before the cache
destruction process beginning, issuing memcg_register_cache() on failure.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Glauber Costa <glommer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Mon, 7 Apr 2014 22:39:26 +0000 (15:39 -0700)]
memcg, slab: separate memcg vs root cache creation paths
Memcg-awareness turned kmem_cache_create() into a dirty interweaving of
memcg-only and except-for-memcg calls. To clean this up, let's move the
code responsible for memcg cache creation to a separate function.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Glauber Costa <glommer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Mon, 7 Apr 2014 22:39:24 +0000 (15:39 -0700)]
memcg, slab: cleanup memcg cache creation
This patch cleans up the memcg cache creation path as follows:
- Move memcg cache name creation to a separate function to be called
from kmem_cache_create_memcg(). This allows us to get rid of the mutex
protecting the temporary buffer used for the name formatting, because
the whole cache creation path is protected by the slab_mutex.
- Get rid of memcg_create_kmem_cache(). This function serves as a proxy
to kmem_cache_create_memcg(). After separating the cache name creation
path, it would be reduced to a function call, so let's inline it.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Glauber Costa <glommer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Mon, 7 Apr 2014 22:39:23 +0000 (15:39 -0700)]
memcg, slab: never try to merge memcg caches
When a kmem cache is created (kmem_cache_create_memcg()), we first try to
find a compatible cache that already exists and can handle requests from
the new cache, i.e. has the same object size, alignment, ctor, etc. If
there is such a cache, we do not create any new caches, instead we simply
increment the refcount of the cache found and return it.
Currently we do this procedure not only when creating root caches, but
also for memcg caches. However, there is no point in that, because, as
every memcg cache has exactly the same parameters as its parent and cache
merging cannot be turned off in runtime (only on boot by passing
"slub_nomerge"), the root caches of any two potentially mergeable memcg
caches should be merged already, i.e. it must be the same root cache, and
therefore we couldn't even get to the memcg cache creation, because it
already exists.
The only exception is boot caches - they are explicitly forbidden to be
merged by setting their refcount to -1. There are currently only two of
them - kmem_cache and kmem_cache_node, which are used in slab internals (I
do not count kmalloc caches as their refcount is set to 1 immediately
after creation). Since they are prevented from merging preliminary I
guess we should avoid to merge their children too.
So let's remove the useless code responsible for merging memcg caches.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Glauber Costa <glommer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Howells [Mon, 7 Apr 2014 22:39:22 +0000 (15:39 -0700)]
asm/system.h: um: arch_align_stack() moved to asm/exec.h
arch_align_stack() moved to asm/exec.h, so change the comment referring to
asm/system.h which no longer exists.
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Howells [Mon, 7 Apr 2014 22:39:21 +0000 (15:39 -0700)]
asm/system.h: clean asm/system.h from docs
Clean asm/system.h from docs as nothing should refer to that header anymore.
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Gideon Israel Dsouza [Mon, 7 Apr 2014 22:39:20 +0000 (15:39 -0700)]
kernel: use macros from compiler.h instead of __attribute__((...))
To increase compiler portability there is <linux/compiler.h> which
provides convenience macros for various gcc constructs. Eg: __weak for
__attribute__((weak)). I've replaced all instances of gcc attributes
with the right macro in the kernel subsystem.
Signed-off-by: Gideon Israel Dsouza <gidisrael@gmail.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Uwe Kleine-König [Mon, 7 Apr 2014 22:39:19 +0000 (15:39 -0700)]
Kconfig: rename HAS_IOPORT to HAS_IOPORT_MAP
If the renamed symbol is defined lib/iomap.c implements ioport_map and
ioport_unmap and currently (nearly) all platforms define the port
accessor functions outb/inb and friend unconditionally. So
HAS_IOPORT_MAP is the better name for this.
Consequently NO_IOPORT is renamed to NO_IOPORT_MAP.
The motivation for this change is to reintroduce a symbol HAS_IOPORT
that signals if outb/int et al are available. I will address that at
least one merge window later though to keep surprises to a minimum and
catch new introductions of (HAS|NO)_IOPORT.
The changes in this commit were done using:
$ git grep -l -E '(NO|HAS)_IOPORT' | xargs perl -p -i -e 's/\b((?:CONFIG_)?(?:NO|HAS)_IOPORT)\b/$1_MAP/'
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Davidlohr Bueso [Mon, 7 Apr 2014 22:39:18 +0000 (15:39 -0700)]
ipc: use device_initcall
... since __initcall is now deprecated.
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Davidlohr Bueso [Mon, 7 Apr 2014 22:39:17 +0000 (15:39 -0700)]
ipc/compat.c: remove sc_semopm macro
This macro appears to have been introduced back in the 2.5 era for
semtimedop32 backward compatibility on ia32:
https://lkml.org/lkml/2003/4/28/78
Nowadays, this syscall in compat just defaults back to the code found in
sem.c, so it is no longer used and can thus be removed:
long compat_sys_semtimedop(int semid, struct sembuf __user *tsems,
unsigned nsops, const struct compat_timespec __user *timeout)
{
struct timespec __user *ts64;
if (compat_convert_timespec(&ts64, timeout))
return -EFAULT;
return sys_semtimedop(semid, tsems, nsops, ts64);
}
Furthermore, there are no users in compat.c. After this change, kernel
builds just fine with both CONFIG_SYSVIPC_COMPAT and CONFIG_SYSVIPC.
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Daniel M. Weeks [Mon, 7 Apr 2014 22:39:16 +0000 (15:39 -0700)]
initramfs: debug detected compression method
This can greatly aid in narrowing down the real source of initramfs
problems such as failures related to the compression of the in-kernel
initramfs when an external initramfs is in use as well. Existing errors
are ambiguous as to which initramfs is a problem and why.
[akpm@linux-foundation.org: use pr_debug()]
Signed-off-by: Daniel M. Weeks <dan@danweeks.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Jones [Mon, 7 Apr 2014 22:39:15 +0000 (15:39 -0700)]
fault-injection: set bounds on what /proc/self/make-it-fail accepts.
/proc/self/make-it-fail is a boolean, but accepts any number, including
negative ones. Change variable to unsigned, and cap upper bound at 1.
[akpm@linux-foundation.org: don't make make_it_fail unsigned]
Signed-off-by: Dave Jones <davej@fedoraproject.org>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josh Triplett [Mon, 7 Apr 2014 22:39:14 +0000 (15:39 -0700)]
x86: always define BUG() and HAVE_ARCH_BUG, even with !CONFIG_BUG
This ensures that BUG() always has a definition that causes a trap (via
an undefined instruction), and that the compiler still recognizes the
code following BUG() as unreachable, avoiding warnings that would
otherwise appear (such as on non-void functions that don't return a
value after BUG()).
In addition to saving a few bytes over the generic infinite-loop
implementation, this implementation traps rather than looping, which
potentially allows for better error-recovery behavior (such as by
rebooting).
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josh Triplett [Mon, 7 Apr 2014 22:39:13 +0000 (15:39 -0700)]
bug: Make BUG() always stop the machine
When !CONFIG_BUG and !HAVE_ARCH_BUG, define the generic BUG() as an
infinite loop rather than a no-op. This avoids undefined behavior if
execution ever actually reaches BUG(), and avoids warnings about code
after BUG() (such as on non-void functions calling BUG() and then not
returning).
bloat-o-meter results:
add/remove: 0/0 grow/shrink: 43/10 up/down: 235/-98 (137)
function old new delta
umount_collect 119 138 +19
notify_change 306 324 +18
xstate_enable_boot_cpu 252 269 +17
kunmap 54 70 +16
balloon_page_dequeue 112 126 +14
mm_take_all_locks 223 233 +10
list_lru_walk_node 143 152 +9
vma_adjust 1059 1067 +8
pcpu_setup_first_chunk 1130 1138 +8
mm_drop_all_locks 143 151 +8
ns_capable 55 62 +7
anon_transport_class_unregister 8 15 +7
srcu_init_notifier_head 35 41 +6
shrink_dcache_for_umount 174 180 +6
kunmap_high 99 105 +6
end_page_writeback 43 49 +6
do_exit 1339 1345 +6
__kfifo_dma_out_prepare_r 86 92 +6
__kfifo_dma_in_prepare_r 90 96 +6
fixup_user_fault 120 125 +5
repair_env_string 73 77 +4
read_cache_pages_invalidate_page 56 60 +4
isolate_lru_pages.isra 142 146 +4
do_notify_parent_cldstop 255 259 +4
cpu_init 370 374 +4
utimes_common 270 272 +2
tasklet_hi_action 91 93 +2
tasklet_action 91 93 +2
set_pte_vaddr 46 48 +2
find_get_pages_tag 202 204 +2
early_iounmap 185 187 +2
__native_set_fixmap 36 38 +2
__get_user_pages 822 824 +2
__early_ioremap 299 301 +2
yield_task_stop 1 2 +1
tick_resume 37 38 +1
switched_to_stop 1 2 +1
switched_to_idle 1 2 +1
prio_changed_stop 1 2 +1
prio_changed_idle 1 2 +1
pm_qos_power_read 111 112 +1
arch_cpu_idle_dead 1 2 +1
__insert_vmap_area 140 141 +1
sys_renameat 614 612 -2
mm_fault_error 297 295 -2
SyS_renameat 614 612 -2
sys_linkat 416 413 -3
SyS_linkat 416 413 -3
chmod_common 129 122 -7
proc_cap_handler 240 225 -15
__schedule 849 831 -18
sys_madvise 1077 1054 -23
SyS_madvise 1077 1054 -23
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josh Triplett [Mon, 7 Apr 2014 22:39:12 +0000 (15:39 -0700)]
bug: when !CONFIG_BUG, make WARN call no_printk to check format and args
The stub version of WARN for !CONFIG_BUG completely ignored its format
string and subsequent arguments; make it check them instead, using
no_printk.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josh Triplett [Mon, 7 Apr 2014 22:39:11 +0000 (15:39 -0700)]
include/asm-generic/bug.h: style fix: s/while(0)/while (0)/
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josh Triplett [Mon, 7 Apr 2014 22:39:10 +0000 (15:39 -0700)]
bug: when !CONFIG_BUG, simplify WARN_ON_ONCE and family
When !CONFIG_BUG, WARN_ON and family become simple passthroughs of their
condition argument; however, WARN_ON_ONCE and family still have conditions
and a boolean to detect one-time invocation, even though the warning
they'd emit doesn't exist. Make the existing definitions conditional on
CONFIG_BUG, and add definitions for !CONFIG_BUG that map to the
passthrough versions of WARN and WARN_ON.
This saves 4.4k on a minimized configuration (smaller than allnoconfig),
and 20.6k with defconfig plus CONFIG_BUG=n.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josh Triplett [Mon, 7 Apr 2014 22:39:09 +0000 (15:39 -0700)]
kconfig: make allnoconfig disable options behind EMBEDDED and EXPERT
"make allnoconfig" exists to ease testing of minimal configurations.
Documentation/SubmitChecklist includes a note to test with allnoconfig.
This helps catch missing dependencies on common-but-not-required
functionality, which might otherwise go unnoticed.
However, allnoconfig still leaves many symbols enabled, because they're
hidden behind CONFIG_EMBEDDED or CONFIG_EXPERT. For instance, allnoconfig
still has CONFIG_PRINTK and CONFIG_BLOCK enabled, so drivers don't
typically get build-tested with those disabled.
To address this, introduce a new Kconfig option "allnoconfig_y", used on
symbols which only exist to hide other symbols. Set it on CONFIG_EMBEDDED
(which then selects CONFIG_EXPERT). allnoconfig will then disable all the
symbols hidden behind those.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josh Triplett [Mon, 7 Apr 2014 22:39:08 +0000 (15:39 -0700)]
ppc: make PPC_BOOK3S_64 select IRQ_WORK
Fix breakage which will be exposed by the patch "kconfig: make allnoconfig
disable options behind EMBEDDED and EXPERT".
arch/powerpc/kernel/mce.c, compiled in for PPC_BOOK3S_64, calls
functions only built when IRQ_WORK, so select it. Fixes the following
build error:
arch/powerpc/kernel/built-in.o: In function `.machine_check_queue_event':
(.text+0x11260): undefined reference to `.irq_work_queue'
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josh Triplett [Mon, 7 Apr 2014 22:39:07 +0000 (15:39 -0700)]
ia64: select CONFIG_TTY for use of tty_write_message in unaligned
Fix breakage which will be exposed by the patch "kconfig: make allnoconfig
disable options behind EMBEDDED and EXPERT".
arch/ia64/kernel/unaligned.c uses tty_write_message to print an
unaligned access exception to the TTY of the current user process.
Enable TTY to prevent a build error.
Minimal fix, on the basis that few people on ia64 will care deeply about
kernel size enough to turn off TTY. Ideally, I'd instead suggest
dropping the tty_write_message entirely, and just leaving the printk.
Bonus: no need to sprintf first.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Geert Uytterhoeven [Mon, 7 Apr 2014 22:39:06 +0000 (15:39 -0700)]
cris: cpuinfo_op should depend on CONFIG_PROC_FS
Fix breakage which will be exposed by the patch "kconfig: make allnoconfig
disable options behind EMBEDDED and EXPERT".
Now allnoconfig started disabling CONFIG_PROC_FS:
arch/cris/kernel/built-in.o:(.rodata+0xc): undefined reference to `show_cpuinfo'
make: *** [vmlinux] Error 1
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josh Triplett [Mon, 7 Apr 2014 22:39:04 +0000 (15:39 -0700)]
cris: make ETRAX_ARCH_V10 select TTY for use in debugport
Fix breakage which will be exposed by the patch "kconfig: make allnoconfig
disable options behind EMBEDDED and EXPERT".
arch/cris/arch-v10/kernel/debugport.c, compiled in unconditionally with
ETRAX_ARCH_V10, requires TTY, so select TTY to avoid a build failure.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dan Carpenter [Mon, 7 Apr 2014 22:39:03 +0000 (15:39 -0700)]
drivers/misc/sgi-gru/grukdump.c: cleanup gru_dump_context() a little
"ret" is zero here so we can remove the "!ret" part of the condition.
"uhdr" is alread a __user pointer so we can remove the cast.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fabian Frederick [Mon, 7 Apr 2014 22:39:03 +0000 (15:39 -0700)]
kernel/panic.c: display reason at end + pr_emerg
Currently, booting without initrd specified on 80x25 screen gives a call
trace followed by atkbd : Spurious ACK. Original message ("VFS: Unable
to mount root fs") is not available. Of course this could happen in
other situations...
This patch displays panic reason after call trace which could help lot
of people even if it's not the very last line on screen.
Also, convert all panic.c printk(KERN_EMERG to pr_emerg(
[akpm@linux-foundation.org: missed a couple of pr_ conversions]
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fabian Frederick [Mon, 7 Apr 2014 22:39:02 +0000 (15:39 -0700)]
fs/bfs/inode.c: add __init to init_inodecache()
init_inodecache is only called by __init init_bfs_fs
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fabian Frederick [Mon, 7 Apr 2014 22:39:01 +0000 (15:39 -0700)]
affs: add mount option to avoid filename truncates
Normal behavior for filenames exceeding specific filesystem limits is to
refuse operation.
AFFS standard name length being only 30 characters against 255 for usual
Linux filesystems, original implementation does filename truncate by
default with a define value AFFS_NO_TRUNCATE which can be enabled but
needs module compilation.
This patch adds 'nofilenametruncate' mount option so that user can
easily activate that feature and avoid a lot of problems (eg overwrite
files ...)
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fabian Frederick [Mon, 7 Apr 2014 22:39:00 +0000 (15:39 -0700)]
fs/affs/dir.c: unlock/brelse dir on failure + code clean-up
Commit
0edf977d2ae3 ("[readdir] convert affs") returns directly -EIO
without unlocking dir inode and releasing dir bh when second affs_bread
sequence fails. This patch restores initial behaviour. It also fixes
pr_debug and affs_error to fit in 80 columns + removes reference to
filldir (replaced by dir_emit in the commit above).
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fabian Frederick [Mon, 7 Apr 2014 22:38:59 +0000 (15:38 -0700)]
affs: add __init to init_inodecache ()
init_inodecache is only called by __init init_affs_fs
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fabian Frederick [Mon, 7 Apr 2014 22:38:58 +0000 (15:38 -0700)]
fs/adfs/super.c: add __init to init_inodecache()
init_inodecache is only called by __init init_adfs_fs.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Liu Hua [Mon, 7 Apr 2014 22:38:57 +0000 (15:38 -0700)]
hung_task: check the value of "sysctl_hung_task_timeout_sec"
As sysctl_hung_task_timeout_sec is unsigned long, when this value is
larger then LONG_MAX/HZ, the function schedule_timeout_interruptible in
watchdog will return immediately without sleep and with print :
schedule_timeout: wrong timeout value
ffffffffffffff83
and then the funtion watchdog will call schedule_timeout_interruptible
again and again. The screen will be filled with
"schedule_timeout: wrong timeout value
ffffffffffffff83"
This patch does some check and correction in sysctl, to let the function
schedule_timeout_interruptible allways get the valid parameter.
Signed-off-by: Liu Hua <sdu.liu@huawei.com>
Tested-by: Satoru Takeuchi <satoru.takeuchi@gmail.com>
Cc: <stable@vger.kernel.org> [3.4+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexandre Bounine [Mon, 7 Apr 2014 22:38:56 +0000 (15:38 -0700)]
rapidio: rework device hierarchy and introduce mport class of devices
This patch removes an artificial RapidIO bus root device and establishes
actual device hierarchy by providing reference to real parent devices.
It also introduces device class for RapidIO controller devices (on-chip
or an eternal bridge, known as "mport").
Existing implementation was sufficient for SoC-based platforms that have
a single RapidIO controller. With introduction of devices using
multiple RapidIO controllers and PCIe-to-RapidIO bridges the old scheme
is very limiting or does not work at all. The implemented changes allow
to properly reference platform's local RapidIO mport devices and provide
device details needed for upper layers.
This change to RapidIO device hierarchy does not break any known
existing kernel or user space interfaces.
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com>
Cc: Stef van Os <stef.van.os@prodrive-technologies.com>
Cc: Jerry Jacobs <jerry.jacobs@prodrive-technologies.com>
Cc: Arno Tiemersma <arno.tiemersma@prodrive-technologies.com>
Cc: Rob Landley <rob@landley.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexandre Bounine [Mon, 7 Apr 2014 22:38:55 +0000 (15:38 -0700)]
drivers/rapidio/devices/tsi721_dma.c: optimize use of BDMA descriptors
Combine SG entries describing single contiguous memory block into one
Tsi721 BDMA descriptor. This reduces number of hardware descriptors
required for large data transfers and improves performance on the PCIe
side by reducing number of descriptor fetch requests.
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Monam Agarwal [Mon, 7 Apr 2014 22:38:54 +0000 (15:38 -0700)]
lib/idr.c: use RCU_INIT_POINTER(x, NULL)
Replace rcu_assign_pointer(x, NULL) with RCU_INIT_POINTER(x, NULL)
The rcu_assign_pointer() ensures that the initialization of a structure
is carried out before storing a pointer to that structure. And in the
case of the NULL pointer, there is no structure to initialize.
So, rcu_assign_pointer(p, NULL) can be safely converted to
RCU_INIT_POINTER(p, NULL)
Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Stephen Hemminger [Mon, 7 Apr 2014 22:38:52 +0000 (15:38 -0700)]
idr: remove dead code
Remove no longer used deprecated code, and make local functions
static.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: George Spelvin <linux@horizon.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
WANG Chao [Mon, 7 Apr 2014 22:38:51 +0000 (15:38 -0700)]
vmcore: continue vmcore initialization if PT_NOTE is found empty
Currently when an empty PT_NOTE is detected, vmcore initialization
fails. It sounds too harsh. Because PT_NOTE could be empty, for
example, one offlined a cpu but never restarted kdump service, and after
crash, PT_NOTE program header is there but no data contains. It's
better to warn about the empty PT_NOTE and continue to initialise
vmcore.
And ultimately the multiple PT_NOTE are merged into a single one, all
empty PT_NOTE are discarded naturally during the merge. So empty
PT_NOTE is not visible to user space and vmcore is as good as expected.
Signed-off-by: WANG Chao <chaowang@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Greg Pearson <greg.pearson@hp.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rashika Kheria [Mon, 7 Apr 2014 22:38:50 +0000 (15:38 -0700)]
include/linux/crash_dump.h: add vmcore_cleanup() prototype
Eliminate the following warning in proc/vmcore.c:
fs/proc/vmcore.c:1088:6: warning: no previous prototype for `vmcore_cleanup' [-Wmissing-prototypes]
[akpm@linux-foundation.org: clean up powerpc, remove unneeded EXPORT_SYMBOL]
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov [Mon, 7 Apr 2014 22:38:49 +0000 (15:38 -0700)]
wait: WSTOPPED|WCONTINUED doesn't work if a zombie leader is traced by another process
Even if the main thread is dead the process still can stop/continue.
However, if the leader is ptraced wait_consider_task(ptrace => false)
always skips wait_task_stopped/wait_task_continued, so WSTOPPED or
WCONTINUED can never work for the natural parent in this case.
Move the "A zombie ptracee is only visible to its ptracer" check into the
"if (!delay_group_leader(p))" block. ->notask_error is cleared by the
"fall through" code below.
This depends on the previous change, wait_task_stopped/continued must be
avoided if !delay_group_leader() and the tracer is ->real_parent.
Otherwise WSTOPPED|WEXITED could wrongly report "stopped" when the child
is already dead (single-threaded or not). If it is traced by another task
then the "stopped" state is fine until the debugger detaches and reveals a
zombie state.
Stupid test-case:
void *tfunc(void *arg)
{
sleep(1); // wait for zombie leader
raise(SIGSTOP);
exit(0x13);
return NULL;
}
int run_child(void)
{
pthread_t thread;
if (!fork()) {
int tracee = getppid();
assert(ptrace(PTRACE_ATTACH, tracee, 0,0) == 0);
do
ptrace(PTRACE_CONT, tracee, 0,0);
while (wait(NULL) > 0);
return 0;
}
sleep(1); // wait for PTRACE_ATTACH
assert(pthread_create(&thread, NULL, tfunc, NULL) == 0);
pthread_exit(NULL);
}
int main(void)
{
int child, stat;
child = fork();
if (!child)
return run_child();
assert(child == waitpid(-1, &stat, WSTOPPED));
assert(stat == 0x137f);
kill(child, SIGCONT);
assert(child == waitpid(-1, &stat, WCONTINUED));
assert(stat == 0xffff);
assert(child == waitpid(-1, &stat, 0));
assert(stat == 0x1300);
return 0;
}
Without this patch it hangs in waitpid(WSTOPPED), wait_task_stopped() is
never called.
Note: this doesn't fix all problems with a zombie delay_group_leader(),
WCONTINUED | WEXITED check is not exactly right. debugger can't assume it
will be notified if another thread reaps the whole thread group.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: Lennart Poettering <lpoetter@redhat.com>
Cc: Michal Schmidt <mschmidt@redhat.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov [Mon, 7 Apr 2014 22:38:47 +0000 (15:38 -0700)]
wait: WSTOPPED|WCONTINUED hangs if a zombie child is traced by real_parent
"A zombie is only visible to its ptracer" logic in wait_consider_task()
is very wrong. Trivial test-case:
#include <unistd.h>
#include <sys/ptrace.h>
#include <sys/wait.h>
#include <assert.h>
int main(void)
{
int child = fork();
if (!child) {
assert(ptrace(PTRACE_TRACEME, 0,0,0) == 0);
return 0x23;
}
assert(waitid(P_ALL, child, NULL, WEXITED | WNOWAIT) == 0);
assert(waitid(P_ALL, 0, NULL, WSTOPPED) == -1);
return 0;
}
it hangs in waitpid(WSTOPPED) despite the fact it has a single zombie
child. This is because wait_consider_task(ptrace => 0) sees p->ptrace and
cleares ->notask_error assuming that the debugger should detach and notify
us.
Change wait_consider_task(ptrace => 0) to pretend that ptrace == T if the
child is traced by us. This really simplifies the logic and allows us to
do more fixes, see the next changes. This also hides the unwanted group
stop state automatically, we can remove another ptrace_reparented() check.
Unfortunately, this adds the following behavioural changes:
1. Before this patch wait(WEXITED | __WNOTHREAD) does not reap
a natural child if it is traced by the caller's sub-thread.
Hopefully nobody will ever notice this change, and I think
that nobody should rely on this behaviour anyway.
2. SIGNAL_STOP_CONTINUED is no longer hidden from debugger if
it is real parent.
While this change comes as a side effect, I think it is good
by itself. The group continued state can not be consumed by
another process in this case, it doesn't depend on ptrace,
it doesn't make sense to hide it from real parent.
Perhaps we should add the thread_group_leader() check before
wait_task_continued()? May be, but this shouldn't depend on
ptrace_reparented().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: Lennart Poettering <lpoetter@redhat.com>
Cc: Michal Schmidt <mschmidt@redhat.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov [Mon, 7 Apr 2014 22:38:46 +0000 (15:38 -0700)]
wait: swap EXIT_ZOMBIE and EXIT_DEAD to hide EXIT_TRACE from user-space
get_task_state() uses the most significant bit to report the state to
user-space, this means that EXIT_ZOMBIE->EXIT_TRACE->EXIT_DEAD transition
can be noticed via /proc as Z -> X -> Z change. Note that this was
possible even before EXIT_TRACE was introduced.
This is not really bad but imho it make sense to hide EXIT_TRACE from
user-space completely. So the patch simply swaps EXIT_ZOMBIE and
EXIT_DEAD, this way EXIT_TRACE will be seen as EXIT_ZOMBIE by user-space.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: Michal Schmidt <mschmidt@redhat.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Lennart Poettering <lpoetter@redhat.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov [Mon, 7 Apr 2014 22:38:45 +0000 (15:38 -0700)]
wait: completely ignore the EXIT_DEAD tasks
Now that EXIT_DEAD is the terminal state it doesn't make sense to call
eligible_child() or security_task_wait() if the task is really dead.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Tested-by: Michal Schmidt <mschmidt@redhat.com>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Lennart Poettering <lpoetter@redhat.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov [Mon, 7 Apr 2014 22:38:43 +0000 (15:38 -0700)]
wait: use EXIT_TRACE only if thread_group_leader(zombie)
wait_task_zombie() always uses EXIT_TRACE/ptrace_unlink() if
ptrace_reparented(). This is suboptimal and a bit confusing: we do not
need do_notify_parent(p) if !thread_group_leader(p) and in this case we
also do not need ptrace_unlink(), we can rely on ptrace_release_task().
Change wait_task_zombie() to check thread_group_leader() along with
ptrace_reparented() and simplify the final p->exit_state transition.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Tested-by: Michal Schmidt <mschmidt@redhat.com>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Lennart Poettering <lpoetter@redhat.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov [Mon, 7 Apr 2014 22:38:42 +0000 (15:38 -0700)]
wait: introduce EXIT_TRACE to avoid the racy EXIT_DEAD->EXIT_ZOMBIE transition
wait_task_zombie() first does EXIT_ZOMBIE->EXIT_DEAD transition and
drops tasklist_lock. If this task is not the natural child and it is
traced, we change its state back to EXIT_ZOMBIE for ->real_parent.
The last transition is racy, this is even documented in
50b8d257486a
"ptrace: partially fix the do_wait(WEXITED) vs EXIT_DEAD->EXIT_ZOMBIE
race". wait_consider_task() tries to detect this transition and clear
->notask_error but we can't rely on ptrace_reparented(), debugger can
exit and do ptrace_unlink() before its sub-thread sets EXIT_ZOMBIE.
And there is another problem which were missed before: this transition
can also race with reparent_leader() which doesn't reset >exit_signal if
EXIT_DEAD, assuming that this task must be reaped by someone else. So
the tracee can be re-parented with ->exit_signal != SIGCHLD, and if
/sbin/init doesn't use __WALL it becomes unreapable. This was fixed by
the previous commit, but it was the temporary hack.
1. Add the new exit_state, EXIT_TRACE. It means that the task is the
traced zombie, debugger is going to detach and notify its natural
parent.
This new state is actually EXIT_ZOMBIE | EXIT_DEAD. This way we
can avoid the changes in proc/kgdb code, get_task_state() still
reports "X (dead)" in this case.
Note: with or without this change userspace can see Z -> X -> Z
transition. Not really bad, but probably makes sense to fix.
2. Change wait_task_zombie() to use EXIT_TRACE instead of EXIT_DEAD
if we need to notify the ->real_parent.
3. Revert the previous hack in reparent_leader(), now that EXIT_DEAD
is always the final state we can safely ignore such a task.
4. Change wait_consider_task() to check EXIT_TRACE separately and kill
the racy and no longer needed ptrace_reparented() case.
If ptrace == T an EXIT_TRACE thread should be simply ignored, the
owner of this state is going to ptrace_unlink() this task. We can
pretend that it was already removed from ->ptraced list.
Otherwise we should skip this thread too but clear ->notask_error,
we must be the natural parent and debugger is going to untrace and
notify us. IOW, this doesn't differ from "EXIT_ZOMBIE && p->ptrace"
even if the task was already untraced.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Jan Kratochvil <jan.kratochvil@redhat.com>
Reported-by: Michal Schmidt <mschmidt@redhat.com>
Tested-by: Michal Schmidt <mschmidt@redhat.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Lennart Poettering <lpoetter@redhat.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov [Mon, 7 Apr 2014 22:38:41 +0000 (15:38 -0700)]
wait: fix reparent_leader() vs EXIT_DEAD->EXIT_ZOMBIE race
wait_task_zombie() first does EXIT_ZOMBIE->EXIT_DEAD transition and
drops tasklist_lock. If this task is not the natural child and it is
traced, we change its state back to EXIT_ZOMBIE for ->real_parent.
The last transition is racy, this is even documented in
50b8d257486a
"ptrace: partially fix the do_wait(WEXITED) vs EXIT_DEAD->EXIT_ZOMBIE
race". wait_consider_task() tries to detect this transition and clear
->notask_error but we can't rely on ptrace_reparented(), debugger can
exit and do ptrace_unlink() before its sub-thread sets EXIT_ZOMBIE.
And there is another problem which were missed before: this transition
can also race with reparent_leader() which doesn't reset >exit_signal if
EXIT_DEAD, assuming that this task must be reaped by someone else. So
the tracee can be re-parented with ->exit_signal != SIGCHLD, and if
/sbin/init doesn't use __WALL it becomes unreapable.
Change reparent_leader() to update ->exit_signal even if EXIT_DEAD.
Note: this is the simple temporary hack for -stable, it doesn't try to
solve all problems, it will be reverted by the next changes.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Jan Kratochvil <jan.kratochvil@redhat.com>
Reported-by: Michal Schmidt <mschmidt@redhat.com>
Tested-by: Michal Schmidt <mschmidt@redhat.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Lennart Poettering <lpoetter@redhat.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov [Mon, 7 Apr 2014 22:38:39 +0000 (15:38 -0700)]
exec: kill bprm->tcomm[], simplify the "basename" logic
Starting from commit
c4ad8f98bef7 ("execve: use 'struct filename *' for
executable name passing") bprm->filename can not go away after
flush_old_exec(), so we do not need to save the binary name in
bprm->tcomm[] added by
96e02d158678 ("exec: fix use-after-free bug in
setup_new_exec()").
And there was never need for filename_to_taskname-like code, we can
simply do set_task_comm(kbasename(filename).
This patch has to change set_task_comm() and trace_task_rename() to
accept "const char *", but I think this change is also good.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Djalal Harouni [Mon, 7 Apr 2014 22:38:38 +0000 (15:38 -0700)]
procfs: make /proc/*/pagemap 0400
The /proc/*/pagemap contain sensitive information and currently its mode
is 0444. Change this to 0400, so the VFS will prevent unprivileged
processes from getting file descriptors on arbitrary privileged
/proc/*/pagemap files.
This reduces the scope of address space leaking and bypasses by protecting
already running processes.
Signed-off-by: Djalal Harouni <tixxdz@opendz.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Djalal Harouni [Mon, 7 Apr 2014 22:38:36 +0000 (15:38 -0700)]
procfs: make /proc/*/{stack,syscall,personality} 0400
These procfs files contain sensitive information and currently their
mode is 0444. Change this to 0400, so the VFS will be able to block
unprivileged processes from getting file descriptors on arbitrary
privileged /proc/*/{stack,syscall,personality} files.
This reduces the scope of ASLR leaking and bypasses by protecting already
running processes.
Signed-off-by: Djalal Harouni <tixxdz@opendz.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Monam Agarwal [Mon, 7 Apr 2014 22:38:35 +0000 (15:38 -0700)]
fs/proc/inode.c: use RCU_INIT_POINTER(x, NULL)
Replace rcu_assign_pointer(x, NULL) with RCU_INIT_POINTER(x, NULL)
The rcu_assign_pointer() ensures that the initialization of a structure
is carried out before storing a pointer to that structure. And in the
case of the NULL pointer, there is no structure to initialize. So,
rcu_assign_pointer(p, NULL) can be safely converted to
RCU_INIT_POINTER(p, NULL)
Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrey Vagin [Mon, 7 Apr 2014 22:38:34 +0000 (15:38 -0700)]
proc: show mnt_id in /proc/pid/fdinfo
Currently we don't have a way how to determing from which mount point
file has been opened. This information is required for proper dumping
and restoring file descriptos due to presence of mount namespaces. It's
possible, that two file descriptors are opened using the same paths, but
one fd references mount point from one namespace while the other fd --
from other namespace.
$ ls -l /proc/1/fd/1
lrwx------ 1 root root 64 Mar 19 23:54 /proc/1/fd/1 -> /dev/null
$ cat /proc/1/fdinfo/1
pos: 0
flags: 0100002
mnt_id: 16
$ cat /proc/1/mountinfo | grep ^16
16 32 0:4 / /dev rw,nosuid shared:2 - devtmpfs devtmpfs rw,size=1013356k,nr_inodes=253339,mode=755
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Rob Landley <rob@landley.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Luiz Capitulino [Mon, 7 Apr 2014 22:38:32 +0000 (15:38 -0700)]
fs/proc/meminfo: meminfo_proc_show(): fix typo in comment
It should read "reclaimable slab" and not "reclaimable swap".
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Rafael Aquini <aquini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Guillaume Morin [Mon, 7 Apr 2014 22:38:31 +0000 (15:38 -0700)]
kernel/exit.c: call proc_exit_connector() after exit_state is set
The process events connector delivers a notification when a process
exits. This is really convenient for a process that spawns and wants to
monitor its children through an epoll-able() interface.
Unfortunately, there is a small window between when the event is
delivered and the child become wait()-able.
This is creates a race if the parent wants to make sure that it knows
about the exit, e.g
pid_t pid = fork();
if (pid > 0) {
register_interest_for_pid(pid);
if (waitpid(pid, NULL, WNOHANG) > 0)
{
/* We might have raced with exit() */
}
return;
}
/* Child */
execve(...)
register_interest_for_pid() would be telling the the connector socket
reader to pay attention to events related to pid.
Though this is not a bug, I think it would make the connector a bit more
usable if this race was closed by simply moving the call to
proc_exit_connector() from just before exit_notify() to right after.
Oleg said:
: Even with this patch the code above is still "racy" if the child is
: multi-threaded. Plus it should obviously filter-out subthreads. And
: afaics there is no way to make it reliable, even if you change the code
: above so that waitpid() is called only after the last thread exits WNOHANG
: still can fail.
Signed-off-by: Guillaume Morin <guillaume@morinfr.org>
Cc: Matt Helsley <matt.helsley@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov [Mon, 7 Apr 2014 22:38:30 +0000 (15:38 -0700)]
exit: move check_stack_usage() to the end of do_exit()
It is not clear why check_stack_usage() is called so early and thus it
never checks the stack usage in, say, exit_notify() or
flush_ptrace_hw_breakpoint() or other functions which are only called by
do_exit().
Move the callsite down to the last preempt_disable/schedule.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov [Mon, 7 Apr 2014 22:38:29 +0000 (15:38 -0700)]
exit: call disassociate_ctty() before exit_task_namespaces()
Commit
8aac62706ada ("move exit_task_namespaces() outside of
exit_notify()") breaks pppd and the exiting service crashes the kernel:
BUG: unable to handle kernel NULL pointer dereference at
0000000000000028
IP: ppp_register_channel+0x13/0x20 [ppp_generic]
Call Trace:
ppp_asynctty_open+0x12b/0x170 [ppp_async]
tty_ldisc_open.isra.2+0x27/0x60
tty_ldisc_hangup+0x1e3/0x220
__tty_hangup+0x2c4/0x440
disassociate_ctty+0x61/0x270
do_exit+0x7f2/0xa50
ppp_register_channel() needs ->net_ns and current->nsproxy == NULL.
Move disassociate_ctty() before exit_task_namespaces(), it doesn't make
sense to delay it after perf_event_exit_task() or cgroup_exit().
This also allows to use task_work_add() inside the (nontrivial) code
paths in disassociate_ctty().
Investigated by Peter Hurley.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Sree Harsha Totakura <sreeharsha@totakura.in>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Sree Harsha Totakura <sreeharsha@totakura.in>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrey Vagin <avagin@openvz.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org> [v3.10+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SeongJae Park [Mon, 7 Apr 2014 22:38:28 +0000 (15:38 -0700)]
mm/zswap.c: remove unnecessary parentheses
Fix following trivial checkpatch error:
ERROR: return is not a function, parentheses are not required
Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Acked-by: Seth Jennings <sjennings@variantweb.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Minchan Kim [Mon, 7 Apr 2014 22:38:27 +0000 (15:38 -0700)]
mm/zswap: support multiple swap devices
Cai Liu reporeted that now zbud pool pages counting has a problem when
multiple swap is used because it just counts only one swap intead of all
of swap so zswap cannot control writeback properly. The result is
unnecessary writeback or no writeback when we should really writeback.
IOW, it made zswap crazy.
Another problem in zswap is:
For example, let's assume we use two swap A and B with different
priority and A already has charged 19% long time ago and let's assume
that A swap is full now so VM start to use B so that B has charged 1%
recently. It menas zswap charged (19% + 1%) is full by default. Then,
if VM want to swap out more pages into B, zbud_reclaim_page would be
evict one of pages in B's pool and it would be repeated continuously.
It's totally LRU reverse problem and swap thrashing in B would happen.
This patch makes zswap consider mutliple swap by creating *a* zbud pool
which will be shared by multiple swap so all of zswap pages in multiple
swap keep order by LRU so it can prevent above two problems.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: Cai Liu <cai.liu@samsung.com>
Suggested-by: Weijie Yang <weijie.yang.kh@gmail.com>
Cc: Seth Jennings <sjennings@variantweb.net>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SeongJae Park [Mon, 7 Apr 2014 22:38:26 +0000 (15:38 -0700)]
mm/zswap.c: update zsmalloc in comment to zbud
zswap used zsmalloc before and now using zbud. But, some comments saying
it use zsmalloc yet. Fix the trivial problems.
Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SeongJae Park [Mon, 7 Apr 2014 22:38:25 +0000 (15:38 -0700)]
mm/zswap.c: fix trivial typo and arrange indentation
Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joonsoo Kim [Mon, 7 Apr 2014 22:38:24 +0000 (15:38 -0700)]
zram: support REQ_DISCARD
zram is ram based block device and can be used by backend of filesystem.
When filesystem deletes a file, it normally doesn't do anything on data
block of that file. It just marks on metadata of that file. This
behavior has no problem on disk based block device, but has problems on
ram based block device, since we can't free memory used for data block.
To overcome this disadvantage, there is REQ_DISCARD functionality. If
block device support REQ_DISCARD and filesystem is mounted with discard
option, filesystem sends REQ_DISCARD to block device whenever some data
blocks are discarded. All we have to do is to handle this request.
This patch implements to flag up QUEUE_FLAG_DISCARD and handle this
REQ_DISCARD request. With it, we can free memory used by zram if it isn't
used.
[akpm@linux-foundation.org: tweak comments]
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Mon, 7 Apr 2014 22:38:22 +0000 (15:38 -0700)]
zram: use scnprintf() in attrs show() methods
sysfs.txt documentation lists the following requirements:
- The buffer will always be PAGE_SIZE bytes in length. On i386, this
is 4096.
- show() methods should return the number of bytes printed into the
buffer. This is the return value of scnprintf().
- show() should always use scnprintf().
Use scnprintf() in show() functions.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Minchan Kim [Mon, 7 Apr 2014 22:38:21 +0000 (15:38 -0700)]
zram: propagate error to user
When we initialized zcomp with single, we couldn't change
max_comp_streams without zram reset but current interface doesn't show
any error to user and even it changes max_comp_streams's value without
any effect so it would make user very confusing.
This patch prevents max_comp_streams's change when zcomp was initialized
as single zcomp and emit the error to user(ex, echo).
[akpm@linux-foundation.org: don't return with the lock held, per Sergey]
[fengguang.wu@intel.com: fix coccinelle warnings]
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>