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In certain circumstances, especially under heavy load, the AUXADC
completion interrupt may be detected after we've timed out waiting for
it. That conversion would still succeed but the next conversion will
see the completion that was signalled by the interrupt for the previous
conversion and therefore not wait for the AUXADC conversion to run,
causing it to report failure.
Provide a simple, non-invasive cleanup by using try_wait_for_completion()
to ensure that the completion is not signalled before we wait. Since
the AUXADC is run within a mutex we know there can only have been at
most one AUXADC interrupt outstanding. A more involved change should
follow for the next merge window.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Export __strncpy_user, memory_size, ioremap_bot for modules.
Signed-off-by: Michal Simek <monstr@monstr.eu>
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Remove eeh_add_device_tree_late which is powerpc specific code.
Signed-off-by: Michal Simek <monstr@monstr.eu>
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CC arch/microblaze/kernel/cpu/cache.o
arch/microblaze/kernel/cpu/cache.c: In function '__invalidate_dcache_range_wb':
arch/microblaze/kernel/cpu/cache.c:398: warning: ISO C90 forbids mixed declarations and code
arch/microblaze/kernel/cpu/cache.c: In function '__flush_dcache_range_wb':
arch/microblaze/kernel/cpu/cache.c:509: warning: ISO C90 forbids mixed declara
Signed-off-by: Michal Simek <monstr@monstr.eu>
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Modules that use copy_{to,from}_user(), memcpy(), and memset() fail to build
in certain circumstances.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
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With dma based spi transmission, data corruption is observed
occasionally. With dma buffers located right next to msg and
xfer fields, cache lines correctly flushed in preparation for
dma usage may be polluted again when writing to fields in the
same cache line.
Make sure cache fields used with dma do not share cache lines
with fields changed during dma handling. As both fields are part
of a struct that is allocated via kzalloc, thus cache aligned,
moving the fields to the 1st position and insert padding for
alignment does the job.
Signed-off-by: Oskar Schirmer <os@emlix.com>
Signed-off-by: Daniel Glöckner <dg@emlix.com>
Signed-off-by: Oliver Schneidewind <osw@emlix.com>
Signed-off-by: Johannes Weiner <jw@emlix.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
[dtor@mail.ru - changed to use ___cacheline_aligned as suggested
by akpm]
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
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Synaptics hardware requires resetting device after suspend to ram
in order for the device to be operational. The reset lives in
synaptics-specific reconnect handler, but it is not being invoked
if synaptics support is disabled and the device is handled as a
standard PS/2 device (bare or IntelliMouse protocol).
Let's add reset into generic reconnect handler as well.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
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Apparently all 3 bytes returned by ETP_FW_VERSION_QUERY are significant
and should be taken into account when matching hardware version/features.
Tested-by: Eric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
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The Microblaze implementations of get_user() and (MMU) put_user() evaluate
the address argument more than once. This causes unexpected side-effects for
invocations that include increment operators, i.e. get_user(foo, bar++).
This patch also removes the distinction between MMU and noMMU put_user().
Without the patch:
$ echo 1234567890 > /proc/sys/kernel/core_pattern
$ cat /proc/sys/kernel/core_pattern
12345
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
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schedule() should not be called with interrupts disabled.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
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Usually "_text" is enough, but I received reports that its not always
available, so fallback to "_stext" for the symbol we use to check if we
need to apply any relocation to all the symbols in the kernel symtab,
for when, for instance, kexec is being used.
Reported-by: Darren Hart <dvhltc@us.ibm.com>
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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An index of KVM44x_GUEST_TLB_SIZE is already one too large.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Acked-by: Hollis Blanchard <hollis@penguinppc.org>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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As the processor may not consider GUEST_INTR_STATE_STI as a reason for
blocking NMI, it could return immediately with EXIT_REASON_NMI_WINDOW
when we asked for it. But as we consider this state as NMI-blocking, we
can run into an endless loop.
Resolve this by allowing NMI injection if just GUEST_INTR_STATE_STI is
active (originally suggested by Gleb). Intel confirmed that this is
safe, the processor will never complain about NMI injection in this
state.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
KVM-Stable-Tag
Acked-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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cpuid_update may operate VMCS, so vcpu_load() and vcpu_put()
should be called to ensure correctness.
Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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This patch makes KVM on 32 bit SVM working again by
correcting the masks used for iret interception. With the
wrong masks the upper 32 bits of the intercepts are masked
out which leaves vmrun unintercepted. This is not legal on
svm and the vmrun fails.
Bug was introduced by commits 95ba827313 and 3cfc3092.
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
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kvm_set_irq is used from non sleepable contexes, so convert ioapic from
mutex to spinlock.
KVM-Stable-Tag.
Tested-by: Ralf Bonenkamp <ralf.bonenkamp@swyx.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc/perf_event: Fix oops due to perf_event_do_pending call
powerpc/swiotlb: Fix off by one in determining boundary of which ops to use
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* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
[S390] correct address of _stext with CONFIG_SHARED_KERNEL=y
[S390] ptrace: fix return value of do_syscall_trace_enter()
[S390] dasd: fix race between tasklet and dasd_sleep_on
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git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
ceph: preserve seq # on requeued messages after transient transport errors
ceph: fix cap removal races
ceph: zero unused message header, footer fields
ceph: fix locking for waking session requests after reconnect
ceph: resubmit requests on pg mapping change (not just primary change)
ceph: fix open file counting on snapped inodes when mds returns no caps
ceph: unregister osd request on failure
ceph: don't use writeback_control in writepages completion
ceph: unregister bdi before kill_anon_super releases device name
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unssigned"
This reverts commit 977d17bb1749517b353874ccdc9b85abc7a58c2a, because it
can cause problems with some devices not getting any resources at all
when the resource tree is re-allocated.
For an example of this, see
https://bugzilla.kernel.org/show_bug.cgi?id=15960
(originally https://bugtrack.alsa-project.org/alsa-bug/view.php?id=4982)
(lkml thread: http://lkml.org/lkml/2010/4/19/20)
where Peter Henriksson reported his Xonar DX sound card gone, because
the IO port region was no longer allocated.
Reported-bisected-and-tested-by: Peter Henriksson <peter.henriksson@gmail.com>
Requested-by: Andrew Morton <akpm@linux-foundation.org>
Requested-by: Clemens Ladisch <clemens@ladisch.de>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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cachefiles_determine_cache_security() is expected to return with a
security override in place. However, if set_create_files_as() fails, we
fail to do this. In this case, we should just reinstate the security
override that was set by the caller.
Furthermore, if set_create_files_as() fails, we should dispose of the
new credentials we were in the process of creating.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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If there are no active threasd using a semaphore, it is always correct
to unqueue blocked threads. This seems to be what was intended in the
undo code.
What was done instead, was to look for a sem count of zero - this is an
impossible situation, given that at least one thread is known to be
queued on the semaphore. The code might be correct as written, but it's
hard to reason about and it's not what was intended (otherwise the goto
out would have been unconditional).
Go for checking the active count - the alternative is not worth the
headache.
Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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According to memory-barriers.txt, an smp memory barrier in guest
should always be paired with an smp memory barrier in host,
and I quote "a lack of appropriate pairing is almost certainly an
error". In case of vhost, failure to flush out used index
update before looking at the interrupt disable flag
could result in missed interrupts, resulting in
networking hang under stress.
This might happen when flags read bypasses used index write.
So we see interrupts disabled and do not interrupt, at the
same time guest writes flags value to enable interrupt,
reads an old used index value, thinks that
used ring is empty and waits for interrupt.
Note: the barrier we pair with here is in
drivers/virtio/virtio_ring.c, function
vring_enable_cb.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Juan Quintela <quintela@redhat.com>
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Fix:
fs/built-in.o: In function `sys_inotify_init1':
summary.c:(.text+0x347a4): undefined reference to `anon_inode_getfd'
found by kautobuild with arms bcmring_defconfig, which ends up with
INOTIFY_USER enabled (through the 'default y') but leaves ANON_INODES
unset. However, inotify_user.c uses anon_inode_getfd().
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Eric Paris <eparis@redhat.com>
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The capture source control of maya44 was wrongly coded with the bit
shift instead of the bit mask. Also, the slot for line-in was
wrongly assigned (slot 5 instead of 4).
Reported-by: Alex Chernyshoff <alexdsp@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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This fixes the build failures seen when building mpcore_wdt and it
also removes the nonexistent ARM_MPCORE_PLATFORM dependency, instead
make it dependent on HAVE_ARM_TWD.
Also this fixes spinlock usage appropriately.
Signed-off-by: srinidhi kasagar <srinidhi.kasagar@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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This moves the TWD register set of MPcore to a common
existing file so that watchdog driver can access it
Signed-off-by: srinidhi kasagar <srinidhi.kasagar@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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MIPS non-coherent archs need the noncached pgprot in mmap of PCM buffers.
But, since the coherency needs to be checked dynamically via
plat_device_is_coherent(), we need an ugly check dependent on MIPS
in ALSA core code.
This should be cleaned up in MIPS arch side (e.g. creating
dma_mmap_coherent()) in near future.
Tested-by: Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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Commit 65c3ac885ce9852852b895a4a62212f62cb5f2e9 in 2.6.33 accidentally
left out the initialization of the AC97 codec FMIC2MIC bit, which broke
recording from the front panel microphone.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: <stable@kernel.org>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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It turned out that HP dv series have inconsistent the mute-LED GPIO
mapping among various models. dv4/7 seem to use GPIO 0 while dv 5/6
seem to use GPIO 3. The previous commit
26ebe0a28986f4845b2c5bea43ac5cc0b9f27f0a
ALSA: hda - Fix mute-LED GPIO pin for HP dv series
breaks dv5/6.
This patch adds the new quirk model, hp-dv4, to handle HP dv4/7
separately from HP dv5/6.
Tested-by: Kunal Gangakhedkar <kunal.gangakhedkar@gmail.com> (for dv6-1110ax)
Acked-by: Kunal Gangakhedkar <kunal.gangakhedkar@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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As of git commit 1844c9bc0b2fed3023551c1affe033ab38e90b9a head64.S/head31.S
are not included in head.S anymore but build as an extra object. This breaks
shared kernel support because the .org statement in head64.S/head31.S for
CONFIG_SHARED_KERNEL=y will have a different effect. The end address of the
head.text section in head.o will be added to the .org value, to compensate
for this subtract 0x11000 to get the required value of 0x100000 again.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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strace may change the system call number, so regs->gprs[2] must not
be read before tracehook_report_syscall_entry(). This fixes a bug
where "strace -f" will hang after a vfork().
Cc: <stable@kernel.org>
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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The various dasd_sleep_on functions use a global wait queue when
waiting for a cqr. The wait condition checks the status and devlist
fields of the cqr to determine if it is safe to continue. This
evaluation may return true, although the tasklet has not finished
processing of the cqr and the callback function has not been called
yet. When the callback is finally called, the data in the cqr may
already be invalid. The sleep_on wait condition needs a safe way to
determine if the tasklet has finished processing. Use the
callback_data field of the cqr to store a token, which is set by
the callback function itself.
Cc: <stable@kernel.org>
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Anton Blanchard found that large POWER systems would occasionally
crash in the exception exit path when profiling with perf_events.
The symptom was that an interrupt would occur late in the exit path
when the MSR[RI] (recoverable interrupt) bit was clear. Interrupts
should be hard-disabled at this point but they were enabled. Because
the interrupt was not recoverable the system panicked.
The reason is that the exception exit path was calling
perf_event_do_pending after hard-disabling interrupts, and
perf_event_do_pending will re-enable interrupts.
The simplest and cleanest fix for this is to use the same mechanism
that 32-bit powerpc does, namely to cause a self-IPI by setting the
decrementer to 1. This means we can remove the tests in the exception
exit path and raw_local_irq_restore.
This also makes sure that the call to perf_event_do_pending from
timer_interrupt() happens within irq_enter/irq_exit. (Note that
calling perf_event_do_pending from timer_interrupt does not mean that
there is a possible 1/HZ latency; setting the decrementer to 1 ensures
that the timer interrupt will happen immediately, i.e. within one
timebase tick, which is a few nanoseconds or 10s of nanoseconds.)
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: stable@kernel.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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If the tcp connection drops and we reconnect to reestablish a stateful
session (with the mds), we need to resend previously sent (and possibly
received) messages with the _same_ seq # so that they can be dropped on
the other end if needed. Only assign a new seq once after the message is
queued.
Signed-off-by: Sage Weil <sage@newdream.net>
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The iterate_session_caps helper traverses the session caps list and tries
to grab an inode reference. However, the __ceph_remove_cap was clearing
the inode backpointer _before_ removing itself from the session list,
causing a null pointer dereference.
Clear cap->ci under protection of s_cap_lock to avoid the race, and to
tightly couple the list and backpointer state. Use a local flag to
indicate whether we are releasing the cap, as cap->session may be modified
by a racing thread in iterate_session_caps.
Signed-off-by: Sage Weil <sage@newdream.net>
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git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
hwmon: (applesmc) Correct sysfs fan error handling
hwmon: (asc7621) Bug fixes
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
kprobes/x86: Fix removed int3 checking order
perf: Fix static strings treated like dynamic ones
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kmap-atomic slot
i915_error_object_create() is called from the timer interrupt and hence
can corrupt the KM_USER0 slot. Use KM_IRQ0 instead.
Reported-by: Jaswinder Singh Rajput <jaswinderlinux@gmail.com>
Tested-by: Jaswinder Singh Rajput <jaswinderlinux@gmail.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The work queue has to be flushed after the device has been made
inaccessible. The patch closes a window during which a work queue might
remain active after the device is removed and would then lead to ACPI
calls with undefined behavior.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Acked-by: Eric Piel <eric.piel@tremplin-utc.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Herrmann <morpheus.ibis@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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In case of aborting because we reach the maximum amount of memory which
can be allocated to message queues per user (RLIMIT_MSGQUEUE), we would
try to free the message area twice when bailing out: first by the error
handling code itself, and then later when cleaning up the inode through
delete_inode().
Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The current allocation does not include the memory required for blanking
lines. So avoid memory corruption when multiple devices are using the DMA
memory near each other.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Some callers (in memcontrol.c) calls css_is_ancestor() without
rcu_read_lock. Because css_is_ancestor() has to access RCU protected
data, it should be under rcu_read_lock().
This makes css_is_ancestor() itself does safe access to RCU protected
area. (At least, "root" can have refcnt==0 if it's not an ancestor of
"child". So, we need rcu_read_lock().)
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Commit ad4ba375373937817404fd92239ef4cadbded23b ("memcg: css_id() must be
called under rcu_read_lock()") modifies memcontol.c for fixing RCU check
message. But Andrew Morton pointed out that the fix doesn't seems sane
and it was just for hidining lockdep messages.
This is a patch for do proper things. Checking again, all places,
accessing without rcu_read_lock, that commit fixies was intentional....
all callers of css_id() has reference count on it. So, it's not necessary
to be under rcu_read_lock().
Considering again, we can use rcu_dereference_check for css_id(). We know
css->id is valid if css->refcnt > 0. (css->id never changes and freed
after css->refcnt going to be 0.)
This patch makes use of rcu_dereference_check() in css_id/depth and remove
unnecessary rcu-read-lock added by the commit.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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acct_exit_ns --> acct_file_reopen deletes timer without check timer
execution on other CPUs. So acct_timeout() can change an unmapped memory.
Signed-off-by: Vitaliy Gusev <vgusev@openvz.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Currently page_address_in_vma() compares vma->anon_vma and
page_anon_vma(page) for parameter check, but in 2.6.34 a vma can have
multiple anon_vmas with anon_vma_chain, so current check does not work.
(For anonymous page shared by multiple processes, some verified (page,vma)
pairs return -EFAULT wrongly.)
We can go to checking all anon_vmas in the "same_vma" chain, but it needs
to meet lock requirement. Instead, we can remove anon_vma check safely
because page_address_in_vma() assumes that page and vma are already
checked to belong to the identical process.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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OOM-killer
Ordinarily, application using hugetlbfs will create mappings with
reserves. For shared mappings, these pages are reserved before mmap()
returns success and for private mappings, the caller process is guaranteed
and a child process that cannot get the pages gets killed with sigbus.
An application that uses MAP_NORESERVE gets no reservations and mmap()
will always succeed at the risk the page will not be available at fault
time. This might be used for example on very large sparse mappings where
the developer is confident the necessary huge pages exist to satisfy all
faults even though the whole mapping cannot be backed by huge pages.
Unfortunately, if an allocation does fail, VM_FAULT_OOM is returned to the
fault handler which proceeds to trigger the OOM-killer. This is
unhelpful.
Even without hugetlbfs mounted, a user using mmap() can trivially trigger
the OOM-killer because VM_FAULT_OOM is returned (will provide example
program if desired - it's a whopping 24 lines long). It could be
considered a DOS available to an unprivileged user.
This patch alters hugetlbfs to kill a process that uses MAP_NORESERVE
where huge pages were not available with SIGBUS instead of triggering the
OOM killer.
This change affects hugetlb_cow() as well. I feel there is a failure case
in there, but I didn't create one. It would need a fairly specific target
in terms of the faulting application and the hugepage pool size. The
hugetlb_no_page() path is much easier to hit but both might as well be
closed.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Two "echo 0 > /sys/kernel/kexec_crash_size" OOPSes kernel. Also content
of this file is invalid after first shrink to zero: it shows 1 instead of
0.
This scenario is unlikely to happen often (root privs, valid crashkernel=
in cmdline, dump-capture kernel not loaded), I hit it only by chance.
This patch fixes it.
Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Cc: Cong Wang <amwang@redhat.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
Mark Brown
Michal Simek
Steven J. Magnani
Takashi Iwai
Oskar Schirmer
Dmitry Torokhov
Arnaldo Carvalho de Melo
Roel Kluin
Jan Kiszka
Dongxiao Xu
Joerg Roedel
Marcelo Tosatti
Linus Torvalds
Benjamin Herrenschmidt
David Howells
Michel Lespinasse
Michael S. Tsirkin
Russell King
Srinidhi Kasagar
Clemens Ladisch
Martin Schwidefsky
Gerald Schaefer
Stefan Weinhuber
Paul Mackerras
Sage Weil
Andrew Morton
Oliver Neukum
André Goddard Rosa
Michael Hennerich
KAMEZAWA Hiroyuki
Vitaliy Gusev
Naoya Horiguchi
Mel Gorman
Vitaly Mayatskikh