Gerlando Falauto reported that when HRTICK is enabled, it is
possible to trigger system deadlocks. These were hard to
reproduce, as HRTICK has been broken in the past, but seemed
to be connected to the timekeeping_seq lock.
Since seqlock/seqcount's aren't supported w/ lockdep, I added
some extra spinlock based locking and triggered the following
lockdep output:
[ 15.849182] ntpd/4062 is trying to acquire lock:
[ 15.849765] (&(&pool->lock)->rlock){..-...}, at: [<ffffffff810aa9b5>] __queue_work+0x145/0x480
[ 15.850051]
[ 15.850051] but task is already holding lock:
[ 15.850051] (timekeeper_lock){-.-.-.}, at: [<ffffffff810df6df>] do_adjtimex+0x7f/0x100
<snip>
[ 15.850051] Chain exists of: &(&pool->lock)->rlock --> &p->pi_lock --> timekeeper_lock
[ 15.850051] Possible unsafe locking scenario:
[ 15.850051]
[ 15.850051] CPU0 CPU1
[ 15.850051] ---- ----
[ 15.850051] lock(timekeeper_lock);
[ 15.850051] lock(&p->pi_lock);
[ 15.850051] lock(timekeeper_lock);
[ 15.850051] lock(&(&pool->lock)->rlock);
[ 15.850051]
[ 15.850051] *** DEADLOCK ***
The deadlock was introduced by 06c017fdd4 ("timekeeping:
Hold timekeepering locks in do_adjtimex and hardpps") in 3.10
This patch avoids this deadlock, by moving the call to
schedule_delayed_work() outside of the timekeeper lock
critical section.
Reported-by: Gerlando Falauto <gerlando.falauto@keymile.com>
Tested-by: Lin Ming <minggr@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: stable <stable@vger.kernel.org> #3.11, 3.10
Link: http://lkml.kernel.org/r/1378943457-27314-1-git-send-email-john.stultz@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
scale_stime() silently assumes that stime < rtime, otherwise
when stime == rtime and both values are big enough (operations
on them do not fit in 32 bits), the resulting scaling stime can
be bigger than rtime. In consequence utime = rtime - stime
results in negative value.
User space visible symptoms of the bug are overflowed TIME
values on ps/top, for example:
$ ps aux | grep rcu
root 8 0.0 0.0 0 0 ? S 12:42 0:00 [rcuc/0]
root 9 0.0 0.0 0 0 ? S 12:42 0:00 [rcub/0]
root 10 62422329 0.0 0 0 ? R 12:42 21114581:37 [rcu_preempt]
root 11 0.1 0.0 0 0 ? S 12:42 0:02 [rcuop/0]
root 12 62422329 0.0 0 0 ? S 12:42 21114581:35 [rcuop/1]
root 10 62422329 0.0 0 0 ? R 12:42 21114581:37 [rcu_preempt]
or overflowed utime values read directly from /proc/$PID/stat
Reference:
https://lkml.org/lkml/2013/8/20/259
Reported-and-tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: stable@vger.kernel.org
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20130904131602.GC2564@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
tick_nohz_full_kick_all() is useful to notify all full dynticks
CPUs that there is a system state change to checkout before
re-evaluating the need for the tick.
Unfortunately this is implemented using smp_call_function_many()
that ignores the local CPU. This CPU also needs to re-evaluate
the tick.
on_each_cpu_mask() is not useful either because we don't want to
re-evaluate the tick state in place but asynchronously from an IPI
to avoid messing up with any random locking scenario.
So lets call tick_nohz_full_kick() from tick_nohz_full_kick_all()
so that the usual irq work takes care of it.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1375460996-16329-4-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull nohz improvements from Frederic Weisbecker:
" It mostly contains fixes and full dynticks off-case optimizations. I believe that
distros want to enable this feature so it seems important to optimize the case
where the "nohz_full=" parameter is empty. ie: I'm trying to remove any performance
regression that comes with NO_HZ_FULL=y when the feature is not used.
This patchset improves the current situation a lot (off-case appears to be around 11% faster
with hackbench, although I guess it may vary depending on the configuration but it should be
significantly faster in any case) now there is still some work to do: I can still observe a
remaining loss of 1.6% throughput seen with hackbench compared to CONFIG_NO_HZ_FULL=n. "
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The vtime delta update performed by get_vtime_delta() always check
that the source of the snapshot is valid.
Meanhile the snapshot updaters that rely on get_vtime_delta() also
set the new snapshot origin. But some of them do this right before
the call to get_vtime_delta(), making its debug check useless.
This is easily fixable by moving the snapshot origin update after
the call to get_vtime_delta(). The order doesn't matter there.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
In order to use static keys with vtime APIs, we'll need to
add static keys headers to vtime.h
hardirq.h then becomes a problem because it needs vtime.h
for irqtime accounting in irq_enter/irq_exit, but it's
often included just to get the irq mask definitions in the
task preempt_count field and the APIs that come along:
in_interrupt(), in_hardirq(), etc...
Some very low level arch headers sometimes need these masks
and APIs such as arch/m68k/include/asm/irqflags.h for example.
But they don't want to include hardirq.h if vtime.h, jump_label.h
and even workqueue.h come along. Including such bloated high
level header from arch headers can quickly result in circular
headers dependency that crash the build.
So let's split hardirq.h in two parts:
* preempt_mask.h that gathers all the preempt_count definitions
and the APIs associated. This one is considered low level and can
be safely included anywhere.
* hardirq.h that includes the previous one. It defines the irq
entry/exit APIs.
To avoid future circular headers dependencies, the preempt_mask.h
inclusion can replace hardirq.h on files that don't implement irq
low level handlers but just need the atomic/context check APIs.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
We plan to use the context tracking static key on inline
vtime APIs. For this we need to include the context tracking
headers from those of vtime.
However vtime headers need to stay low level because they are
included in hardirq.h that mostly contains standalone
definitions. But context_tracking.h includes sched.h for
a few task_struct references, therefore it wouldn't be sensible
to include it from vtime.h
To solve this, lets split the context tracking headers and move
out the pure state definitions that only require a few low level
headers. We can safely include that small part in vtime.h later.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
get_vtime_delta() must be called under the task vtime_seqlock
with the code that does the cputime accounting flush.
Otherwise the cputime reader can be fooled and run into
a race where it sees the snapshot update but misses the
cputime flush. As a result it can report a cputime that is
way too short.
Fix vtime_account_user() that wasn't complying to that rule.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
Optimize user and exception entry/exit APIs with static
keys. This minimize the overhead for those who enable
CONFIG_NO_HZ_FULL without always using it. Having no range
passed to nohz_full= should result in the probes to be nopped
(at least we hope so...).
If this proves not be enough in the long term, we'll need
to bring an exception slow path by re-routing the exception
handlers.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
Now that the full dynticks subsystem only enables the context tracking
on full dynticks CPUs, lets remove the dependency on CONTEXT_TRACKING_FORCE
This dependency was a hack to enable the context tracking widely for the
full dynticks susbsystem until the latter becomes able to enable it in a
more CPU-finegrained fashion.
Now CONTEXT_TRACKING_FORCE only stands for testing on archs that
work on support for the context tracking while full dynticks can't be
used yet due to unmet dependencies. It simulates a system where all CPUs
are full dynticks so that RCU user extended quiescent states and dynticks
cputime accounting can be tested on the given arch.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
The context tracking subsystem has the ability to selectively
enable the tracking on any defined subset of CPU. This means that
we can define a CPU range that doesn't run the context tracking
and another range that does.
Now what we want in practice is to enable the tracking on full
dynticks CPUs only. In order to perform this, we just need to pass
our full dynticks CPU range selection from the full dynticks
subsystem to the context tracking.
This way we can spare the overhead of RCU user extended quiescent
state and vtime maintainance on the CPUs that are outside the
full dynticks range. Just keep in mind the raw context tracking
itself is still necessary everywhere.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
As long as the context tracking is enabled on any CPU, even
a single one, all other CPUs need to keep track of their
user <-> kernel boundaries cross as well.
This is because a task can sleep while servicing an exception
that happened in the kernel or in userspace. Then when the task
eventually wakes up and return from the exception, the CPU needs
to know if we resume in userspace or in the kernel. exception_exit()
get this information from exception_enter() that saved the previous
state.
If the CPU where the exception happened didn't keep track of
these informations, exception_exit() doesn't know which state
tracking to restore on the CPU where the task got migrated
and we may return to userspace with the context tracking
subsystem thinking that we are in kernel mode.
This can be fixed in the long term if we move our context tracking
probes on very low level arch fast path user <-> kernel boundary,
although even that is worrisome as an exception can still happen
in the few instructions between the probe and the actual iret.
Also we are not yet ready to set these probes in the fast path given
the potential overhead problem it induces.
So let's fix this by always enable context tracking even on CPUs
that are not in the full dynticks range. OTOH we can spare the
rcu_user_*() and vtime_user_*() calls there because the tick runs
on these CPUs and we can handle RCU state machine and cputime
accounting through it.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
1) If context tracking is enabled with native vtime accounting (which
combo is useless except for dev testing), we call vtime_guest_enter()
and vtime_guest_exit() on host <-> guest switches. But those are stubs
in this configurations. As a result, cputime is not correctly flushed
on kvm context switches.
2) If context tracking runs but is disabled on some CPUs, those
CPUs end up calling __guest_enter/__guest_exit which in turn
call vtime_account_system(). We don't want to call this because we
run in tick based accounting for these CPUs.
Refactor the guest_enter/guest_exit code such that all combinations
finally work.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
Pull SCSI fixes from James Bottomley:
"This is three bug fixes: An fnic warning caused by sleeping under a
lock, a major regression with our updated WRITE SAME/UNMAP logic which
caused tons of USB devices (and one RAID card) to cease to function
and a megaraid_sas firmware initialisation problem which causes kdump
failures"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
[SCSI] Don't attempt to send extended INQUIRY command if skip_vpd_pages is set
[SCSI] fnic: BUG: sleeping function called from invalid context during probe
[SCSI] megaraid_sas: megaraid_sas driver init fails in kdump kernel
Pull powerpc fixes from Ben Herrenschmidt:
"This includes small series from Michael Neuling to fix a couple of
nasty remaining problems with the new Power8 support, also targeted at
stable 3.10, without which some new userspace accessible registers
aren't properly context switched, and in some case, can be clobbered
by the user of transactional memory.
Along with that, a few slightly more minor things, such as a missing
Kconfig option to enable handling of denorm exceptions when not
running under a hypervisor (or userspace will randomly crash when
hitting denorms with the vector unit), some nasty bugs in the new
pstore oops code, and other simple bug fixes worth having in now.
Note: I picked up the two powerpc KVM fixes as Alex Graf asked me to
handle KVM bits while he is on vacation. However I'll let him decide
whether they should go to -stable or not when he is back"
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc/tm: Fix context switching TAR, PPR and DSCR SPRs
powerpc: Save the TAR register earlier
powerpc: Fix context switch DSCR on POWER8
powerpc: Rework setting up H/FSCR bit definitions
powerpc: Fix hypervisor facility unavaliable vector number
powerpc/kvm/book3s_pr: Return appropriate error when allocation fails
powerpc/kvm: Add signed type cast for comparation
powerpc/eeh: Add missing procfs entry for PowerNV
powerpc/pseries: Add backward compatibilty to read old kernel oops-log
powerpc/pseries: Fix buffer overflow when reading from pstore
powerpc: On POWERNV enable PPC_DENORMALISATION by default
Pull s390 kvm fixes from Paolo Bonzini:
"Two fixes for s390"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: s390: fix pfmf non-quiescing control handling
KVM: s390: move kvm_guest_enter,exit closer to sie
Pull i2c fixes from Wolfram Sang:
"Some driver bugfixes for the I2C subsystem"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: mv64xxx: Document the newly introduced allwinner compatible
i2c: Fix Kontron PLD prescaler calculation
i2c: i2c-mxs: Use DMA mode even for small transfers
Pull btrfs fixes from Chris Mason:
"These are assorted fixes, mostly from Josef nailing down xfstests
runs. Zach also has a long standing fix for problems with readdir
wrapping f_pos (or ctx->pos)
These patches were spread out over different bases, so I rebased
things on top of rc4 and retested overnight"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: don't loop on large offsets in readdir
Btrfs: check to see if root_list is empty before adding it to dead roots
Btrfs: release both paths before logging dir/changed extents
Btrfs: allow splitting of hole em's when dropping extent cache
Btrfs: make sure the backref walker catches all refs to our extent
Btrfs: fix backref walking when we hit a compressed extent
Btrfs: do not offset physical if we're compressed
Btrfs: fix extent buffer leak after backref walking
Btrfs: fix a bug of snapshot-aware defrag to make it work on partial extents
btrfs: fix file truncation if FALLOC_FL_KEEP_SIZE is specified
Pull NFS client bugfixes from Trond Myklebust:
- Stable patch for lockd to fix Oopses due to inappropriate calls to
utsname()->nodename
- Stable patches for sunrpc to fix Oopses on shutdown when using
AF_LOCAL sockets with rpcbind
- Fix memory leak and error checking issues in nfs4_proc_lookup_mountpoint
- Fix a regression with the sync mount option failing to work for nfs4
mounts
- Fix a writeback performance issue when doing cache invalidation
- Remove an incorrect call to nfs_setsecurity in nfs_fhget
* tag 'nfs-for-3.11-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv4: Fix up nfs4_proc_lookup_mountpoint
NFS: Remove unnecessary call to nfs_setsecurity in nfs_fhget()
NFSv4: Fix the sync mount option for nfs4 mounts
NFS: Fix writeback performance issue on cache invalidation
SUNRPC: If the rpcbind channel is disconnected, fail the call to unregister
SUNRPC: Don't auto-disconnect from the local rpcbind socket
LOCKD: Don't call utsname()->nodename from nlmclnt_setlockargs
Pull nfsd fixes from Bruce Fields:
"Some fixes for a 4.1 feature that in retrospect probably should have
waited for 3.12.... But it appears to be working now"
* 'for-3.11' of git://linux-nfs.org/~bfields/linux:
nfsd: Fix SP4_MACH_CRED negotiation in EXCHANGE_ID
nfsd4: Fix MACH_CRED NULL dereference
Pull sound fixes from Takashi Iwai:
"A couple of USB-audio fixes that should also go to stable kernels"
* tag 'sound-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: usb-audio: do not trust too-big wMaxPacketSize values
ALSA: 6fire: fix DMA issues with URB transfer_buffer usage
Pull staging driver fixes from Greg KH:
"Here are 3 small fixes for staging/IIO drivers for 3.11-rc5. Nothing
huge, two IIO driver fixes, and a zcache fix. All of these have been
in linux-next for a while"
* tag 'staging-3.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: zcache: fix "zcache=" kernel parameter
iio: ti_am335x_adc: Fix wrong samples received on 1st read
iio:trigger: Fix use_count race condition
Pull USB fixes from Greg KH:
"Here are 3 small USB fixes for 3.11-rc5.
One is a fix that the ChromeOS developers ran into on some Intel
hardware, one is a build fix, and the last is a MAINTAINERS update to
help people figure out where to send USB network driver patches.
All of these have been in linux-next for a while"
* tag 'usb-3.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
MAINTAINERS: Add separate section for USB NETWORKING DRIVERS
usb: xhci: add missing dma-mapping.h includes
usb: core: don't try to reset_device() a port that got just disconnected
When btrfs readdir() hits the last entry it sets the readdir offset to a
huge value to stop buggy apps from breaking when the same name is
returned by readdir() with concurrent rename()s.
But unconditionally setting the offset to INT_MAX causes readdir() to
loop returning any entries with offsets past INT_MAX. It only takes a
few hours of constant file creation and removal to create entries past
INT_MAX.
So let's set the huge offset to LLONG_MAX if the last entry has already
overflowed 32bit loff_t. Without large offsets behaviour is identical.
With large offsets 64bit apps will work and 32bit apps will be no more
broken than they currently are if they see large offsets.
Signed-off-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
A user reported a panic when running with autodefrag and deleting snapshots.
This is because we could end up trying to add the root to the dead roots list
twice. To fix this check to see if we are empty before adding ourselves to the
dead roots list. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
The ceph guys tripped over this bug where we were still holding onto the
original path that we used to copy the inode with when logging. This is based
on Chris's fix which was reported to fix the problem. We need to drop the paths
in two cases anyway so just move the drop up so that we don't have duplicate
code. Thanks,
Cc: stable@vger.kernel.org
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
I noticed while running multi-threaded fsync tests that sometimes fsck would
complain about an improper gap. This happens because we fail to add a hole
extent to the file, which was happening when we'd split a hole EM because
btrfs_drop_extent_cache was just discarding the whole em instead of splitting
it. So this patch fixes this by allowing us to split a hole em properly, which
means that added holes actually get logged properly and we no longer see this
fsck error. Thankfully we're tolerant of these sort of problems so a user would
not see any adverse effects of this bug, other than fsck complaining. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Because we don't mess with the offset into the extent for compressed we will
properly find both extents for this case
[extent a][extent b][rest of extent a]
but because we already added a ref for the front half we won't add the inode
information for the second half. This causes us to leak that memory and not
print out the other offset when we do logical-resolve. So fix this by calling
ulist_add_merge and then add our eie to the existing entry if there is one.
With this patch we get both offsets out of logical-resolve. With this and the
other 2 patches I've sent we now pass btrfs/276 on my vm with compress-force=lzo
set. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
If you do btrfs inspect-internal logical-resolve on a compressed extent that has
been partly overwritten it won't find anything. This is because we try and
match the extent offset we've searched for based on the extent offset in the
data extent entry. However this doesn't work for compressed extents because the
offsets are for the uncompressed size, not the compressed size. So instead only
do this check if we are not compressed, that way we can get an actual entry for
the physical offset rather than nothing for compressed. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
xfstest btrfs/276 was freaking out on slower boxes partly because fiemap was
offsetting the physical based on the extent offset. This is perfectly fine with
uncompressed extents, however the extent offset is into the uncompressed area,
not the compressed. So we can return a physical value that isn't at all within
the area we have allocated on disk. Fix this by returning the start of the
extent if it is compressed no matter what the offset. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
commit 47fb091fb787420cd195e66f162737401cce023f(Btrfs: fix unlock after free on rewinded tree blocks)
takes an extra increment on the reference of allocated dummy extent buffer, so now we
cannot free this dummy one, and end up with extent buffer leak.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
For partial extents, snapshot-aware defrag does not work as expected,
since
a) we use the wrong logical offset to search for parents, which should be
disk_bytenr + extent_offset, not just disk_bytenr,
b) 'offset' returned by the backref walking just refers to key.offset, not
the 'offset' stored in btrfs_extent_data_ref which is
(key.offset - extent_offset).
The reproducer:
$ mkfs.btrfs sda
$ mount sda /mnt
$ btrfs sub create /mnt/sub
$ for i in `seq 5 -1 1`; do dd if=/dev/zero of=/mnt/sub/foo bs=5k count=1 seek=$i conv=notrunc oflag=sync; done
$ btrfs sub snap /mnt/sub /mnt/snap1
$ btrfs sub snap /mnt/sub /mnt/snap2
$ sync; btrfs filesystem defrag /mnt/sub/foo;
$ umount /mnt
$ btrfs-debug-tree sda (Here we can check whether the defrag operation is snapshot-awared.
This addresses the above two problems.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Create a small file and fallocate it to a big size with
FALLOC_FL_KEEP_SIZE option, then truncate it back to the
small size again, the disk free space is not changed back
in this case. i.e,
total 4
-rw-r--r-- 1 root root 512 Jun 28 11:35 test
Filesystem Size Used Avail Use% Mounted on
....
/dev/sdb1 8.0G 56K 7.2G 1% /mnt
-rw-r--r-- 1 root root 512 Jun 28 11:35 /mnt/test
Filesystem Size Used Avail Use% Mounted on
....
/dev/sdb1 8.0G 5.1G 2.2G 70% /mnt
Filesystem Size Used Avail Use% Mounted on
....
/dev/sdb1 8.0G 5.1G 2.2G 70% /mnt
With this fix, the truncated up space is back as:
Filesystem Size Used Avail Use% Mounted on
....
/dev/sdb1 8.0G 56K 7.2G 1% /mnt
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Pull ACPI and power management fixes from Rafael Wysocki:
- ACPI-based memory hotplug stopped working after a recent change,
because it's not possible to associate sufficiently many "physical"
devices with one ACPI device object due to an artificial limit. Fix
from Rafael J Wysocki removes that limit and makes memory hotplug
work again.
- A change made in 3.9 uncovered a bug in the ACPI processor driver
preventing NUMA nodes from being put offline due to an ordering
issue. Fix from Yasuaki Ishimatsu changes the ordering to make
things work again.
- One of the recent ACPI video commits (that hasn't been reverted so
far) uncovered a bug in the code handling quirky BIOSes that caused
some Asus machines to boot with backlight completely off which made
it quite difficult to use them afterward. Fix from Felipe Contreras
improves the quirk to cover this particular case correctly.
- A cpufreq user space interface change made in 3.10 inadvertently
renamed the ignore_nice_load sysfs attribute to ignore_nice which
resulted in some confusion. Fix from Viresh Kumar changes the name
back to ignore_nice_load.
- An initialization ordering change made in 3.9 broke cpufreq on
loongson2 boards. Fix from Aaro Koskinen restores the correct
initialization ordering there.
- Fix breakage resulting from a mistake made in 3.9 and causing the
detection of some graphics adapters (that were detected correctly
before) to fail. There are two objects representing the same PCIe
port in the affected systems' ACPI tables and both appear as
"enabled" and we are expected to guess which one to use. We used to
choose the right one before by pure luck, but when we tried to
address another similar corner case, the luck went away. This time
we try to make our guessing a bit more educated which is reported to
work on those systems.
- The /proc/acpi/wakeup interface code is missing some locking which
may lead to breakage if that file is written or read during hotplug
of wakeup devices. That should be rare but still possible, so it's
better to start using the appropriate locking there.
* tag 'pm+acpi-3.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: Try harder to resolve _ADR collisions for bridges
cpufreq: rename ignore_nice as ignore_nice_load
cpufreq: loongson2: fix regression related to clock management
ACPI / processor: move try_offline_node() after acpi_unmap_lsapic()
ACPI: Drop physical_node_id_bitmap from struct acpi_device
ACPI / PM: Walk physical_node_list under physical_node_lock
ACPI / video: improve quirk check in acpi_video_bqc_quirk()