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>
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>
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>
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>
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>
Commit 65c3ac885c 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>
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
26ebe0a289
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>
As of git commit 1844c9bc0b 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>
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>
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>
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>
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>
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>
CIFS has stubs for XFS-style quotas without an actual implementation backing
them, hidden behind a config option not visible in Kconfig. Remove these
stubs for now as the quota operations will see some major changes and this
code simply gets in the way.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Steve French <sfrench@us.ibm.com>
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>
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>
Commit ad4ba37537 ("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>
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>
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>
Michael S. Tsirkin
Russell King
Takashi Iwai
Srinidhi Kasagar
Clemens Ladisch
Martin Schwidefsky
Gerald Schaefer
Stefan Weinhuber
Paul Mackerras
Sage Weil
Steve French
Linus Torvalds
Andrew Morton
Oliver Neukum
André Goddard Rosa
Michael Hennerich
KAMEZAWA Hiroyuki
Vitaliy Gusev
Naoya Horiguchi