In a later patch, we're going to need some atomic bit flags. Since that
field will need to be an unsigned long, we mitigate that space
consumption by migrating some other bitflags to the new field. Start
with the rq_secure flag.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Highlights include:
Features:
- NFSv4.2 client support for hole punching and preallocation.
- Further RPC/RDMA client improvements.
- Add more RPC transport debugging tracepoints.
- Add RPC debugging tools in debugfs.
Bugfixes:
- Stable fix for layoutget error handling
- Fix a change in COMMIT behaviour resulting from the recent io code updates
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Merge tag 'nfs-for-3.19-1' into nfsd for-3.19 branch
Mainly what I need is 860a0d9e51 "sunrpc: add some tracepoints in
svc_rqst handling functions", which subsequent server rpc patches from
jlayton depend on. I'm merging this later tag on the assumption that's
more likely to be a tested and stable point.
My static checker complains that if "len == remaining" then it means we
have truncated the last character off the version string.
The intent of the code is that we print as many versions as we can
without truncating a version. Then we put a newline at the end. If the
newline can't fit we return -EINVAL.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently, it leaks when the allocation fails.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
All it does is indicate whether a xprt has already been deleted from
a list or not, which is unnecessary since we use list_del_init and it's
always set and checked under the sv_lock anyway.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add a new directory heirarchy under the debugfs sunrpc/ directory:
sunrpc/
rpc_xprt/
<xprt id>/
Within that directory, we can put files that give info about the
xprts. We do have the (minor) problem that there is no succinct,
unique identifier for rpc_xprts. So we generate them synthetically
with a static atomic_t counter.
For now, this directory just holds an "info" file, but we may add
other files to it in the future.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
It's possible to get a dump of the RPC task queue by writing a value to
/proc/sys/sunrpc/rpc_debug. If you write any value to that file, you get
a dump of the RPC client task list into the log buffer. This is a rather
inconvenient interface however, and makes it hard to get immediate info
about the task queue.
Add a new directory hierarchy under debugfs:
sunrpc/
rpc_clnt/
<clientid>/
Within each clientid directory we create a new "tasks" file that will
dump info similar to what shows up in the log buffer, but with a few
small differences -- we avoid printing raw kernel addresses in favor of
symbolic names and the XID is also displayed.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
These patches various bugfixes and cleanups for using NFS over RDMA, including
better error handling and performance improvements by using pad optimization.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
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Merge tag 'nfs-rdma-for-3.19' of git://git.linux-nfs.org/projects/anna/nfs-rdma into linux-next
Pull NFS client RDMA changes for 3.19 from Anna Schumaker:
"NFS: Client side changes for RDMA
These patches various bugfixes and cleanups for using NFS over RDMA, including
better error handling and performance improvements by using pad optimization.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>"
* tag 'nfs-rdma-for-3.19' of git://git.linux-nfs.org/projects/anna/nfs-rdma:
xprtrdma: Display async errors
xprtrdma: Enable pad optimization
xprtrdma: Re-write rpcrdma_flush_cqs()
xprtrdma: Refactor tasklet scheduling
xprtrdma: unmap all FMRs during transport disconnect
xprtrdma: Cap req_cqinit
xprtrdma: Return an errno from rpcrdma_register_external()
These patches fixes for iostats and SETCLIENTID in addition to cleaning
up the nfs4_init_callback() function.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
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Merge tag 'nfs-cel-for-3.19' of git://git.linux-nfs.org/projects/anna/nfs-rdma into linux-next
Pull pull additional NFS client changes for 3.19 from Anna Schumaker:
"NFS: Generic client side changes from Chuck
These patches fixes for iostats and SETCLIENTID in addition to cleaning
up the nfs4_init_callback() function.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>"
* tag 'nfs-cel-for-3.19' of git://git.linux-nfs.org/projects/anna/nfs-rdma:
NFS: Clean up nfs4_init_callback()
NFS: SETCLIENTID XDR buffer sizes are incorrect
SUNRPC: serialize iostats updates
This patch adds support for using the NFS v4.2 operation DEALLOCATE to
punch holes in a file.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This patch adds support for using the NFS v4.2 operation ALLOCATE to
preallocate data in a file.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
nfs4_init_callback() is never invoked for NFS versions other than 4.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Use the correct calculation of the maximum size of a clientaddr4
when encoding and decoding SETCLIENTID operations. clientaddr4 is
defined in section 2.2.10 of RFC3530bis-31.
The usage in encode_setclientid_maxsz is missing the 4-byte length
in both strings, but is otherwise correct. decode_setclientid_maxsz
simply asks for a page of receive buffer space, which is
unnecessarily large (more than 4KB).
Note that a SETCLIENTID reply is either clientid+verifier, or
clientaddr4, depending on the returned NFS status. It doesn't
hurt to allocate enough space for both.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Occasionally mountstats reports a negative retransmission rate.
Ensure that two RPCs completing concurrently don't confuse the sums
in the transport's op_metrics array.
Since pNFS filelayout can invoke rpc_count_iostats() on another
transport from xprt_release(), we can't rely on simply holding the
transport_lock in xprt_release(). There's nothing for it but hard
serialization. One spin lock per RPC operation should make this as
painless as it can be.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
An async error upcall is a hard error, and should be reported in
the system log.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The Linux NFS/RDMA server used to reject NFSv3 WRITE requests when
pad optimization was enabled. That bug was fixed by commit
e560e3b510 ("svcrdma: Add zero padding if the client doesn't send
it").
We can now enable pad optimization on the client, which helps
performance and is supported now by both Linux and Solaris servers.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Currently rpcrdma_flush_cqs() attempts to avoid code duplication,
and simply invokes rpcrdma_recvcq_upcall and rpcrdma_sendcq_upcall.
1. rpcrdma_flush_cqs() can run concurrently with provider upcalls.
Both flush_cqs() and the upcalls were invoking ib_poll_cq() in
different threads using the same wc buffers (ep->rep_recv_wcs
and ep->rep_send_wcs), added by commit 1c00dd0776 ("xprtrmda:
Reduce calls to ib_poll_cq() in completion handlers").
During transport disconnect processing, this sometimes resulted
in the same reply getting added to the rpcrdma_tasklets_g list
more than once, which corrupted the list.
2. The upcall functions drain only a limited number of CQEs,
thanks to the poll budget added by commit 8301a2c047
("xprtrdma: Limit work done by completion handler").
Fixes: a7bc211ac9 ("xprtrdma: On disconnect, don't ignore ... ")
BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=276
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Restore the separate function that schedules the reply handling
tasklet. I need to call it from two different paths.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When using RPCRDMA_MTHCAFMR memory registration, after a few
transport disconnect / reconnect cycles, ib_map_phys_fmr() starts to
return EINVAL because the provider has exhausted its map pool.
Make sure that all FMRs are unmapped during transport disconnect,
and that ->send_request remarshals them during an RPC retransmit.
This resets the transport's MRs to ensure that none are leaked
during a disconnect.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Recent work made FRMR registration and invalidation completions
unsignaled. This greatly reduces the adapter interrupt rate.
Every so often, however, a posted send Work Request is allowed to
signal. Otherwise, the provider's Work Queue will wrap and the
workload will hang.
The number of Work Requests that are allowed to remain unsignaled is
determined by the value of req_cqinit. Currently, this is set to the
size of the send Work Queue divided by two, minus 1.
For FRMR, the send Work Queue is the maximum number of concurrent
RPCs (currently 32) times the maximum number of Work Requests an
RPC might use (currently 7, though some adapters may need more).
For mlx4, this is 224 entries. This leaves completion signaling
disabled for 111 send Work Requests.
Some providers hold back dispatching Work Requests until a CQE is
generated. If completions are disabled, then no CQEs are generated
for quite some time, and that can stall the Work Queue.
I've seen this occur running xfstests generic/113 over NFSv4, where
eventually, posting a FAST_REG_MR Work Request fails with -ENOMEM
because the Work Queue has overflowed. The connection is dropped
and re-established.
Cap the rep_cqinit setting so completions are not left turned off
for too long.
BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=269
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The RPC/RDMA send_request method and the chunk registration code
expects an errno from the registration function. This allows
the upper layers to distinguish between a recoverable failure
(for example, temporary memory exhaustion) and a hard failure
(for example, a bug in the registration logic).
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Define and use nfs_inc_fscache_stats when plus one, which can save to
pass one parameter.
Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The nfs_put_client() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
It's always set to the same value as CONFIG_TRACEPOINTS, so we can just
use that instead.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
It's always set to whatever CONFIG_SUNRPC_DEBUG is, so just use that.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
LOCKD_DEBUG is always the same value as CONFIG_SUNRPC_DEBUG, so we can
just use it instead.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
nfs4_layoutget_release() drops layout hdr refcnt. Grab the refcnt
early so that it is safe to call .release in case nfs4_alloc_pages
fails.
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Fixes: a47970ff78 ("NFSv4.1: Hold reference to layout hdr in layoutget")
Cc: stable@vger.kernel.org # 3.9+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Recent work in the pgio layer made it possible for there to be more than one
request per page. This caused a subtle change in commit behavior, because
write.c:nfs_commit_unstable_pages compares the number of *pages* waiting for
writeback against the number of requests on a commit list to choose when to
send a COMMIT in a non-blocking flush.
This is probably hard to hit in normal operation - you have to be using
rsize/wsize < PAGE_SIZE, or pnfs with lots of boundaries that are not page
aligned to have a noticeable change in behavior.
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Use the number of pages in the pagecache mapping instead of the
number of pnfs requests which is only slightly related.
Reported-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Add tracepoints inside the main loop on xs_tcp_data_recv that allow
us to keep an eye on what's happening during each phase of it.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
...so we can keep track of when calls are sent and replies received.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
...just around svc_send, svc_recv and svc_process for now.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This should make the code easier to maintain in the future.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
NFS4ERR_ACCESS has number 13 and thus is matched and returned
immediately at the beginning of nfs4_map_errors() and there's no point
in checking it later.
Coverity-id: 733891
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
x86 call do_notify_resume on paranoid returns if TIF_UPROBE is set but
not on non-paranoid returns. I suspect that this is a mistake and that
the code only works because int3 is paranoid.
Setting _TIF_NOTIFY_RESUME in the uprobe code was probably a workaround
for the x86 bug. With that bug fixed, we can remove _TIF_NOTIFY_RESUME
from the uprobes code.
Reported-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Chris bisected a NULL pointer deference in task_sched_runtime() to
commit 6e998916df 'sched/cputime: Fix clock_nanosleep()/clock_gettime()
inconsistency'.
Chris observed crashes in atop or other /proc walking programs when he
started fork bombs on his machine. He assumed that this is a new exit
race, but that does not make any sense when looking at that commit.
What's interesting is that, the commit provides update_curr callbacks
for all scheduling classes except stop_task and idle_task.
While nothing can ever hit that via the clock_nanosleep() and
clock_gettime() interfaces, which have been the target of the commit in
question, the author obviously forgot that there are other code paths
which invoke task_sched_runtime()
do_task_stat(()
thread_group_cputime_adjusted()
thread_group_cputime()
task_cputime()
task_sched_runtime()
if (task_current(rq, p) && task_on_rq_queued(p)) {
update_rq_clock(rq);
up->sched_class->update_curr(rq);
}
If the stats are read for a stomp machine task, aka 'migration/N' and
that task is current on its cpu, this will happily call the NULL pointer
of stop_task->update_curr. Ooops.
Chris observation that this happens faster when he runs the fork bomb
makes sense as the fork bomb will kick migration threads more often so
the probability to hit the issue will increase.
Add the missing update_curr callbacks to the scheduler classes stop_task
and idle_task. While idle tasks cannot be monitored via /proc we have
other means to hit the idle case.
Fixes: 6e998916df 'sched/cputime: Fix clock_nanosleep()/clock_gettime() inconsistency'
Reported-by: Chris Mason <clm@fb.com>
Reported-and-tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge x86-64 iret fixes from Andy Lutomirski:
"This addresses the following issues:
- an unrecoverable double-fault triggerable with modify_ldt.
- invalid stack usage in espfix64 failed IRET recovery from IST
context.
- invalid stack usage in non-espfix64 failed IRET recovery from IST
context.
It also makes a good but IMO scary change: non-espfix64 failed IRET
will now report the correct error. Hopefully nothing depended on the
old incorrect behavior, but maybe Wine will get confused in some
obscure corner case"
* emailed patches from Andy Lutomirski <luto@amacapital.net>:
x86_64, traps: Rework bad_iret
x86_64, traps: Stop using IST for #SS
x86_64, traps: Fix the espfix64 #DF fixup and rewrite it in C
It's possible for iretq to userspace to fail. This can happen because
of a bad CS, SS, or RIP.
Historically, we've handled it by fixing up an exception from iretq to
land at bad_iret, which pretends that the failed iret frame was really
the hardware part of #GP(0) from userspace. To make this work, there's
an extra fixup to fudge the gs base into a usable state.
This is suboptimal because it loses the original exception. It's also
buggy because there's no guarantee that we were on the kernel stack to
begin with. For example, if the failing iret happened on return from an
NMI, then we'll end up executing general_protection on the NMI stack.
This is bad for several reasons, the most immediate of which is that
general_protection, as a non-paranoid idtentry, will try to deliver
signals and/or schedule from the wrong stack.
This patch throws out bad_iret entirely. As a replacement, it augments
the existing swapgs fudge into a full-blown iret fixup, mostly written
in C. It's should be clearer and more correct.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On a 32-bit kernel, this has no effect, since there are no IST stacks.
On a 64-bit kernel, #SS can only happen in user code, on a failed iret
to user space, a canonical violation on access via RSP or RBP, or a
genuine stack segment violation in 32-bit kernel code. The first two
cases don't need IST, and the latter two cases are unlikely fatal bugs,
and promoting them to double faults would be fine.
This fixes a bug in which the espfix64 code mishandles a stack segment
violation.
This saves 4k of memory per CPU and a tiny bit of code.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There's nothing special enough about the espfix64 double fault fixup to
justify writing it in assembly. Move it to C.
This also fixes a bug: if the double fault came from an IST stack, the
old asm code would return to a partially uninitialized stack frame.
Fixes: 3891a04aaf
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A collection of fixes this week:
- A set of clock fixes for shmobile platforms
- A fix for tegra that moves serial port labels to be per board.
We're choosing to merge this for 3.18 because the labels will start
being parsed in 3.19, and without this change serial port numbers that
used to be stable since the dawn of time will change numbers.
- A few other DT tweaks for Tegra.
- A fix for multi_v7_defconfig that makes it stop spewing cpufreq errors on
Arndale (Exynos).
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Merge tag 'armsoc-for-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Olof Johansson:
"A collection of fixes this week:
- A set of clock fixes for shmobile platforms
- A fix for tegra that moves serial port labels to be per board.
We're choosing to merge this for 3.18 because the labels will start
being parsed in 3.19, and without this change serial port numbers
that used to be stable since the dawn of time will change numbers.
- A few other DT tweaks for Tegra.
- A fix for multi_v7_defconfig that makes it stop spewing cpufreq
errors on Arndale (Exynos)"
* tag 'armsoc-for-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
ARM: multi_v7_defconfig: fix failure setting CPU voltage by enabling dependent I2C controller
ARM: tegra: roth: Fix SD card VDD_IO regulator
ARM: tegra: Remove eMMC vmmc property for roth/tn7
ARM: dts: tegra: move serial aliases to per-board
ARM: tegra: Add serial port labels to Tegra124 DT
ARM: shmobile: kzm9g legacy: Set i2c clks_per_count to 2
ARM: shmobile: r8a7740 dtsi: Correct IIC0 parent clock
ARM: shmobile: r8a7790: Fix SD3CKCR address to device tree
ARM: shmobile: r8a7740 legacy: Correct IIC0 parent clock
ARM: shmobile: r8a7740 legacy: Add missing INTCA clock for irqpin module
ARM: shmobile: r8a7790: Fix SD3CKCR address
ARM: dts: sun6i: Re-parent ahb1_mux to pll6 as required by dma controller
Pull percpu fix from Tejun Heo:
"This contains one patch to fix a race condition which can lead to
percpu_ref using a percpu pointer which is corrupted with a set DEAD
bit. The bug was introduced while separating out the ATOMIC mode flag
from the DEAD flag. The fix is pretty straight forward.
I just committed the patch to the percpu tree but am sending out the
pull request early as I'll be on vacation for a week. The patch
should be fairly safe and while the latency will be higher I'll be
checking emails"
* 'for-3.18-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
percpu-ref: fix DEAD flag contamination of percpu pointer
Pull btrfs deadlock fix from Chris Mason:
"This has a fix for a long standing deadlock that we've been trying to
nail down for a while. It ended up being a bad interaction with the
fair reader/writer locks and the order btrfs reacquires locks in the
btree"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: fix lockups from btrfs_clear_path_blocking
While decoupling ATOMIC and DEAD flags, f47ad45784 ("percpu_ref:
decouple switching to percpu mode and reinit") updated
__ref_is_percpu() so that it only tests ATOMIC flag to determine
whether the ref is in percpu mode or not; however, while DEAD implies
ATOMIC, the two flags are set separately during percpu_ref_kill() and
if __ref_is_percpu() races percpu_ref_kill(), it may see DEAD w/o
ATOMIC. Because __ref_is_percpu() returns @ref->percpu_count_ptr
value verbatim as the percpu pointer after testing ATOMIC, the pointer
may now be contaminated with the DEAD flag.
This can be fixed by clearing the flag bits before returning the
pointer which was the fix proposed by Shaohua; however, as DEAD
implies ATOMIC, we can just test for both flags at once and avoid the
explicit masking.
Update __ref_is_percpu() so that it tests that both ATOMIC and DEAD
are clear before returning @ref->percpu_count_ptr as the percpu
pointer.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-Reviewed-by: Shaohua Li <shli@kernel.org>
Link: http://lkml.kernel.org/r/995deb699f5b873c45d667df4add3b06f73c2c25.1416638887.git.shli@kernel.org
Fixes: f47ad45784 ("percpu_ref: decouple switching to percpu mode and reinit")
Pull timer fix from Thomas Gleixner:
"A single bugfix for an init order problem in the sun4i subarch
clockevents code"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
clockevent: sun4i: Fix race condition in the probe code
Pull vfs fixes from Al Viro:
"Assorted fixes, most in overlayfs land"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ovl: ovl_dir_fsync() cleanup
ovl: update MAINTAINERS
ovl: pass dentry into ovl_dir_read_merged()
ovl: use lockless_dereference() for upperdentry
ovl: allow filenames with comma
ovl: fix race in private xattr checks
ovl: fix remove/copy-up race
ovl: rename filesystem type to "overlay"
isofs: avoid unused function warning
vfs: fix reference leak in d_prune_aliases()
