1. 05 8月, 2016 4 次提交
    • G
      blk-mq: Allow timeouts to run while queue is freezing · 71f79fb3
      Gabriel Krisman Bertazi 提交于
      In case a submitted request gets stuck for some reason, the block layer
      can prevent the request starvation by starting the scheduled timeout work.
      If this stuck request occurs at the same time another thread has started
      a queue freeze, the blk_mq_timeout_work will not be able to acquire the
      queue reference and will return silently, thus not issuing the timeout.
      But since the request is already holding a q_usage_counter reference and
      is unable to complete, it will never release its reference, preventing
      the queue from completing the freeze started by first thread.  This puts
      the request_queue in a hung state, forever waiting for the freeze
      completion.
      
      This was observed while running IO to a NVMe device at the same time we
      toggled the CPU hotplug code. Eventually, once a request got stuck
      requiring a timeout during a queue freeze, we saw the CPU Hotplug
      notification code get stuck inside blk_mq_freeze_queue_wait, as shown in
      the trace below.
      
      [c000000deaf13690] [c000000deaf13738] 0xc000000deaf13738 (unreliable)
      [c000000deaf13860] [c000000000015ce8] __switch_to+0x1f8/0x350
      [c000000deaf138b0] [c000000000ade0e4] __schedule+0x314/0x990
      [c000000deaf13940] [c000000000ade7a8] schedule+0x48/0xc0
      [c000000deaf13970] [c0000000005492a4] blk_mq_freeze_queue_wait+0x74/0x110
      [c000000deaf139e0] [c00000000054b6a8] blk_mq_queue_reinit_notify+0x1a8/0x2e0
      [c000000deaf13a40] [c0000000000e7878] notifier_call_chain+0x98/0x100
      [c000000deaf13a90] [c0000000000b8e08] cpu_notify_nofail+0x48/0xa0
      [c000000deaf13ac0] [c0000000000b92f0] _cpu_down+0x2a0/0x400
      [c000000deaf13b90] [c0000000000b94a8] cpu_down+0x58/0xa0
      [c000000deaf13bc0] [c0000000006d5dcc] cpu_subsys_offline+0x2c/0x50
      [c000000deaf13bf0] [c0000000006cd244] device_offline+0x104/0x140
      [c000000deaf13c30] [c0000000006cd40c] online_store+0x6c/0xc0
      [c000000deaf13c80] [c0000000006c8c78] dev_attr_store+0x68/0xa0
      [c000000deaf13cc0] [c0000000003974d0] sysfs_kf_write+0x80/0xb0
      [c000000deaf13d00] [c0000000003963e8] kernfs_fop_write+0x188/0x200
      [c000000deaf13d50] [c0000000002e0f6c] __vfs_write+0x6c/0xe0
      [c000000deaf13d90] [c0000000002e1ca0] vfs_write+0xc0/0x230
      [c000000deaf13de0] [c0000000002e2cdc] SyS_write+0x6c/0x110
      [c000000deaf13e30] [c000000000009204] system_call+0x38/0xb4
      
      The fix is to allow the timeout work to execute in the window between
      dropping the initial refcount reference and the release of the last
      reference, which actually marks the freeze completion.  This can be
      achieved with percpu_refcount_tryget, which does not require the counter
      to be alive.  This way the timeout work can do it's job and terminate a
      stuck request even during a freeze, returning its reference and avoiding
      the deadlock.
      
      Allowing the timeout to run is just a part of the fix, since for some
      devices, we might get stuck again inside the device driver's timeout
      handler, should it attempt to allocate a new request in that path -
      which is a quite common action for Abort commands, which need to be sent
      after a timeout.  In NVMe, for instance, we call blk_mq_alloc_request
      from inside the timeout handler, which will fail during a freeze, since
      it also tries to acquire a queue reference.
      
      I considered a similar change to blk_mq_alloc_request as a generic
      solution for further device driver hangs, but we can't do that, since it
      would allow new requests to disturb the freeze process.  I thought about
      creating a new function in the block layer to support unfreezable
      requests for these occasions, but after working on it for a while, I
      feel like this should be handled in a per-driver basis.  I'm now
      experimenting with changes to the NVMe timeout path, but I'm open to
      suggestions of ways to make this generic.
      Signed-off-by: NGabriel Krisman Bertazi <krisman@linux.vnet.ibm.com>
      Cc: Brian King <brking@linux.vnet.ibm.com>
      Cc: Keith Busch <keith.busch@intel.com>
      Cc: linux-nvme@lists.infradead.org
      Cc: linux-block@vger.kernel.org
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      Signed-off-by: NJens Axboe <axboe@fb.com>
      71f79fb3
    • V
      block: fix use-after-free in seq file · 77da1605
      Vegard Nossum 提交于
      I got a KASAN report of use-after-free:
      
          ==================================================================
          BUG: KASAN: use-after-free in klist_iter_exit+0x61/0x70 at addr ffff8800b6581508
          Read of size 8 by task trinity-c1/315
          =============================================================================
          BUG kmalloc-32 (Not tainted): kasan: bad access detected
          -----------------------------------------------------------------------------
      
          Disabling lock debugging due to kernel taint
          INFO: Allocated in disk_seqf_start+0x66/0x110 age=144 cpu=1 pid=315
                  ___slab_alloc+0x4f1/0x520
                  __slab_alloc.isra.58+0x56/0x80
                  kmem_cache_alloc_trace+0x260/0x2a0
                  disk_seqf_start+0x66/0x110
                  traverse+0x176/0x860
                  seq_read+0x7e3/0x11a0
                  proc_reg_read+0xbc/0x180
                  do_loop_readv_writev+0x134/0x210
                  do_readv_writev+0x565/0x660
                  vfs_readv+0x67/0xa0
                  do_preadv+0x126/0x170
                  SyS_preadv+0xc/0x10
                  do_syscall_64+0x1a1/0x460
                  return_from_SYSCALL_64+0x0/0x6a
          INFO: Freed in disk_seqf_stop+0x42/0x50 age=160 cpu=1 pid=315
                  __slab_free+0x17a/0x2c0
                  kfree+0x20a/0x220
                  disk_seqf_stop+0x42/0x50
                  traverse+0x3b5/0x860
                  seq_read+0x7e3/0x11a0
                  proc_reg_read+0xbc/0x180
                  do_loop_readv_writev+0x134/0x210
                  do_readv_writev+0x565/0x660
                  vfs_readv+0x67/0xa0
                  do_preadv+0x126/0x170
                  SyS_preadv+0xc/0x10
                  do_syscall_64+0x1a1/0x460
                  return_from_SYSCALL_64+0x0/0x6a
      
          CPU: 1 PID: 315 Comm: trinity-c1 Tainted: G    B           4.7.0+ #62
          Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
           ffffea0002d96000 ffff880119b9f918 ffffffff81d6ce81 ffff88011a804480
           ffff8800b6581500 ffff880119b9f948 ffffffff8146c7bd ffff88011a804480
           ffffea0002d96000 ffff8800b6581500 fffffffffffffff4 ffff880119b9f970
          Call Trace:
           [<ffffffff81d6ce81>] dump_stack+0x65/0x84
           [<ffffffff8146c7bd>] print_trailer+0x10d/0x1a0
           [<ffffffff814704ff>] object_err+0x2f/0x40
           [<ffffffff814754d1>] kasan_report_error+0x221/0x520
           [<ffffffff8147590e>] __asan_report_load8_noabort+0x3e/0x40
           [<ffffffff83888161>] klist_iter_exit+0x61/0x70
           [<ffffffff82404389>] class_dev_iter_exit+0x9/0x10
           [<ffffffff81d2e8ea>] disk_seqf_stop+0x3a/0x50
           [<ffffffff8151f812>] seq_read+0x4b2/0x11a0
           [<ffffffff815f8fdc>] proc_reg_read+0xbc/0x180
           [<ffffffff814b24e4>] do_loop_readv_writev+0x134/0x210
           [<ffffffff814b4c45>] do_readv_writev+0x565/0x660
           [<ffffffff814b8a17>] vfs_readv+0x67/0xa0
           [<ffffffff814b8de6>] do_preadv+0x126/0x170
           [<ffffffff814b92ec>] SyS_preadv+0xc/0x10
      
      This problem can occur in the following situation:
      
      open()
       - pread()
          - .seq_start()
             - iter = kmalloc() // succeeds
             - seqf->private = iter
          - .seq_stop()
             - kfree(seqf->private)
       - pread()
          - .seq_start()
             - iter = kmalloc() // fails
          - .seq_stop()
             - class_dev_iter_exit(seqf->private) // boom! old pointer
      
      As the comment in disk_seqf_stop() says, stop is called even if start
      failed, so we need to reinitialise the private pointer to NULL when seq
      iteration stops.
      
      An alternative would be to set the private pointer to NULL when the
      kmalloc() in disk_seqf_start() fails.
      
      Cc: stable@vger.kernel.org
      Signed-off-by: NVegard Nossum <vegard.nossum@oracle.com>
      Acked-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJens Axboe <axboe@fb.com>
      77da1605
    • P
      block: add missing group association in bio-cloning functions · 20bd723e
      Paolo Valente 提交于
      When a bio is cloned, the newly created bio must be associated with
      the same blkcg as the original bio (if BLK_CGROUP is enabled). If
      this operation is not performed, then the new bio is not associated
      with any group, and the group of the current task is returned when
      the group of the bio is requested.
      
      Depending on the cloning frequency, this may cause a large
      percentage of the bios belonging to a given group to be treated
      as if belonging to other groups (in most cases as if belonging to
      the root group). The expected group isolation may thereby be broken.
      
      This commit adds the missing association in bio-cloning functions.
      
      Fixes: da2f0f74 ("Btrfs: add support for blkio controllers")
      Cc: stable@vger.kernel.org # v4.3+
      Signed-off-by: NPaolo Valente <paolo.valente@linaro.org>
      Reviewed-by: NNikolay Borisov <kernel@kyup.com>
      Reviewed-by: NJeff Moyer <jmoyer@redhat.com>
      Acked-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJens Axboe <axboe@fb.com>
      20bd723e
    • H
      blkcg: kill unused field nr_undestroyed_grps · bfd279a8
      Hou Tao 提交于
      'nr_undestroyed_grps' in struct throtl_data was used to count
      the number of throtl_grp related with throtl_data, but now
      throtl_grp is tracked by blkcg_gq, so it is useless anymore.
      Signed-off-by: NHou Tao <houtao1@huawei.com>
      Signed-off-by: NJens Axboe <axboe@fb.com>
      bfd279a8
  2. 04 8月, 2016 1 次提交
  3. 21 7月, 2016 11 次提交
  4. 14 7月, 2016 1 次提交
  5. 08 7月, 2016 1 次提交
  6. 07 7月, 2016 1 次提交
    • T
      timers: Remove set_timer_slack() leftovers · 53bf837b
      Thomas Gleixner 提交于
      We now have implicit batching in the timer wheel. The slack API is no longer
      used, so remove it.
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Alan Stern <stern@rowland.harvard.edu>
      Cc: Andrew F. Davis <afd@ti.com>
      Cc: Arjan van de Ven <arjan@infradead.org>
      Cc: Chris Mason <clm@fb.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
      Cc: Eric Dumazet <edumazet@google.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: George Spelvin <linux@sciencehorizons.net>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Jaehoon Chung <jh80.chung@samsung.com>
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: John Stultz <john.stultz@linaro.org>
      Cc: Josh Triplett <josh@joshtriplett.org>
      Cc: Len Brown <lenb@kernel.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mathias Nyman <mathias.nyman@intel.com>
      Cc: Pali Rohár <pali.rohar@gmail.com>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Sebastian Reichel <sre@kernel.org>
      Cc: Ulf Hansson <ulf.hansson@linaro.org>
      Cc: linux-block@vger.kernel.org
      Cc: linux-kernel@vger.kernel.org
      Cc: linux-mmc@vger.kernel.org
      Cc: linux-pm@vger.kernel.org
      Cc: linux-usb@vger.kernel.org
      Cc: netdev@vger.kernel.org
      Cc: rt@linutronix.de
      Link: http://lkml.kernel.org/r/20160704094342.189813118@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      53bf837b
  7. 06 7月, 2016 2 次提交
  8. 01 7月, 2016 1 次提交
    • O
      block: fix use-after-free in sys_ioprio_get() · 8ba86821
      Omar Sandoval 提交于
      get_task_ioprio() accesses the task->io_context without holding the task
      lock and thus can race with exit_io_context(), leading to a
      use-after-free. The reproducer below hits this within a few seconds on
      my 4-core QEMU VM:
      
      #define _GNU_SOURCE
      #include <assert.h>
      #include <unistd.h>
      #include <sys/syscall.h>
      #include <sys/wait.h>
      
      int main(int argc, char **argv)
      {
      	pid_t pid, child;
      	long nproc, i;
      
      	/* ioprio_set(IOPRIO_WHO_PROCESS, 0, IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0)); */
      	syscall(SYS_ioprio_set, 1, 0, 0x6000);
      
      	nproc = sysconf(_SC_NPROCESSORS_ONLN);
      
      	for (i = 0; i < nproc; i++) {
      		pid = fork();
      		assert(pid != -1);
      		if (pid == 0) {
      			for (;;) {
      				pid = fork();
      				assert(pid != -1);
      				if (pid == 0) {
      					_exit(0);
      				} else {
      					child = wait(NULL);
      					assert(child == pid);
      				}
      			}
      		}
      
      		pid = fork();
      		assert(pid != -1);
      		if (pid == 0) {
      			for (;;) {
      				/* ioprio_get(IOPRIO_WHO_PGRP, 0); */
      				syscall(SYS_ioprio_get, 2, 0);
      			}
      		}
      	}
      
      	for (;;) {
      		/* ioprio_get(IOPRIO_WHO_PGRP, 0); */
      		syscall(SYS_ioprio_get, 2, 0);
      	}
      
      	return 0;
      }
      
      This gets us KASAN dumps like this:
      
      [   35.526914] ==================================================================
      [   35.530009] BUG: KASAN: out-of-bounds in get_task_ioprio+0x7b/0x90 at addr ffff880066f34e6c
      [   35.530009] Read of size 2 by task ioprio-gpf/363
      [   35.530009] =============================================================================
      [   35.530009] BUG blkdev_ioc (Not tainted): kasan: bad access detected
      [   35.530009] -----------------------------------------------------------------------------
      
      [   35.530009] Disabling lock debugging due to kernel taint
      [   35.530009] INFO: Allocated in create_task_io_context+0x2b/0x370 age=0 cpu=0 pid=360
      [   35.530009] 	___slab_alloc+0x55d/0x5a0
      [   35.530009] 	__slab_alloc.isra.20+0x2b/0x40
      [   35.530009] 	kmem_cache_alloc_node+0x84/0x200
      [   35.530009] 	create_task_io_context+0x2b/0x370
      [   35.530009] 	get_task_io_context+0x92/0xb0
      [   35.530009] 	copy_process.part.8+0x5029/0x5660
      [   35.530009] 	_do_fork+0x155/0x7e0
      [   35.530009] 	SyS_clone+0x19/0x20
      [   35.530009] 	do_syscall_64+0x195/0x3a0
      [   35.530009] 	return_from_SYSCALL_64+0x0/0x6a
      [   35.530009] INFO: Freed in put_io_context+0xe7/0x120 age=0 cpu=0 pid=1060
      [   35.530009] 	__slab_free+0x27b/0x3d0
      [   35.530009] 	kmem_cache_free+0x1fb/0x220
      [   35.530009] 	put_io_context+0xe7/0x120
      [   35.530009] 	put_io_context_active+0x238/0x380
      [   35.530009] 	exit_io_context+0x66/0x80
      [   35.530009] 	do_exit+0x158e/0x2b90
      [   35.530009] 	do_group_exit+0xe5/0x2b0
      [   35.530009] 	SyS_exit_group+0x1d/0x20
      [   35.530009] 	entry_SYSCALL_64_fastpath+0x1a/0xa4
      [   35.530009] INFO: Slab 0xffffea00019bcd00 objects=20 used=4 fp=0xffff880066f34ff0 flags=0x1fffe0000004080
      [   35.530009] INFO: Object 0xffff880066f34e58 @offset=3672 fp=0x0000000000000001
      [   35.530009] ==================================================================
      
      Fix it by grabbing the task lock while we poke at the io_context.
      
      Cc: stable@vger.kernel.org
      Reported-by: NDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: NOmar Sandoval <osandov@fb.com>
      Signed-off-by: NJens Axboe <axboe@fb.com>
      8ba86821
  9. 28 6月, 2016 5 次提交
    • J
      cfq-iosched: Charge at least 1 jiffie instead of 1 ns · 0b31c10c
      Jan Kara 提交于
      Commit 9a7f38c4 (cfq-iosched: Convert from jiffies to nanoseconds)
      could result in charging just 1 ns to a cgroup submitting IO instead of 1
      jiffie we always charged before. It is arguable what is the right amount
      to change but for now lets retain the old behavior of always charging at
      least one jiffie.
      
      Fixes: 9a7f38c4Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@fb.com>
      0b31c10c
    • J
      cfq-iosched: Fix regression in bonnie++ rewrite performance · 149321a6
      Jan Kara 提交于
      Commit 9a7f38c4 (cfq-iosched: Convert from jiffies to nanoseconds)
      broke the condition for detecting starved sync IO in
      cfq_completed_request() because rq->start_time remained in jiffies but
      we compared it with nanosecond values. This manifested as a regression
      in bonnie++ rewrite performance because we always ended up considering
      sync IO starved and thus never increased async IO queue depth.
      
      Since rq->start_time is used in a lot of places, converting it to ns
      values would be non-trivial. So just revert the condition in CFQ to use
      comparison with jiffies. This will lead to suboptimal results if
      cfq_fifo_expire[1] will ever come close to 1 jiffie but so far we are
      relatively far from that with the storage used with CFQ (the default
      value is 128 ms).
      
      Fixes: 9a7f38c4Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@fb.com>
      149321a6
    • J
      cfq-iosched: Convert slice_resid from u64 to s64 · 93fdf147
      Jan Kara 提交于
      slice_resid can be both positive and negative. Commit 9a7f38c4
      (cfq-iosched: Convert from jiffies to nanoseconds) converted it from
      long to u64. Although this did not introduce any functional regression
      (the operations just overflow and the result was fine), it is certainly
      wrong and could cause issues in future. So convert the type to more
      appropriate s64.
      
      Fixes: 9a7f38c4Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@fb.com>
      93fdf147
    • J
      block: Convert fifo_time from ulong to u64 · 9828c2c6
      Jan Kara 提交于
      Currently rq->fifo_time is unsigned long but CFQ stores nanosecond
      timestamp in it which would overflow on 32-bit archs. Convert it to u64
      to avoid the overflow. Since the rq->fifo_time is unioned with struct
      call_single_data(), this does not change the size of struct request in
      any way.
      
      We have to slightly fixup block/deadline-iosched.c so that comparison
      happens in the right types.
      
      Fixes: 9a7f38c4Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@fb.com>
      9828c2c6
    • D
      block: remove ->driverfs_dev · 52c44d93
      Dan Williams 提交于
      Now that all drivers that specify a ->driverfs_dev have been converted
      to device_add_disk(), the pointer can be removed from struct gendisk.
      
      Cc: Jens Axboe <axboe@fb.com>
      Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
      Signed-off-by: NDan Williams <dan.j.williams@intel.com>
      52c44d93
  10. 16 6月, 2016 1 次提交
  11. 14 6月, 2016 3 次提交
  12. 10 6月, 2016 1 次提交
    • J
      cfq-iosched: temporarily boost queue priority for idle classes · b8269db4
      Jens Axboe 提交于
      If we're queuing REQ_PRIO IO and the task is running at an idle IO
      class, then temporarily boost the priority. This prevents livelocks
      due to priority inversion, when a low priority task is holding file
      system resources while attempting to do IO.
      
      An example of that is shown below. An ioniced idle task is holding
      the directory mutex, while a normal priority task is trying to do
      a directory lookup.
      
      [478381.198925] ------------[ cut here ]------------
      [478381.200315] INFO: task ionice:1168369 blocked for more than 120 seconds.
      [478381.201324]       Not tainted 4.0.9-38_fbk5_hotfix1_2936_g85409c6 #1
      [478381.202278] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
      [478381.203462] ionice          D ffff8803692736a8     0 1168369      1 0x00000080
      [478381.203466]  ffff8803692736a8 ffff880399c21300 ffff880276adcc00 ffff880369273698
      [478381.204589]  ffff880369273fd8 0000000000000000 7fffffffffffffff 0000000000000002
      [478381.205752]  ffffffff8177d5e0 ffff8803692736c8 ffffffff8177cea7 0000000000000000
      [478381.206874] Call Trace:
      [478381.207253]  [<ffffffff8177d5e0>] ? bit_wait_io_timeout+0x80/0x80
      [478381.208175]  [<ffffffff8177cea7>] schedule+0x37/0x90
      [478381.208932]  [<ffffffff8177f5fc>] schedule_timeout+0x1dc/0x250
      [478381.209805]  [<ffffffff81421c17>] ? __blk_run_queue+0x37/0x50
      [478381.210706]  [<ffffffff810ca1c5>] ? ktime_get+0x45/0xb0
      [478381.211489]  [<ffffffff8177c407>] io_schedule_timeout+0xa7/0x110
      [478381.212402]  [<ffffffff810a8c2b>] ? prepare_to_wait+0x5b/0x90
      [478381.213280]  [<ffffffff8177d616>] bit_wait_io+0x36/0x50
      [478381.214063]  [<ffffffff8177d325>] __wait_on_bit+0x65/0x90
      [478381.214961]  [<ffffffff8177d5e0>] ? bit_wait_io_timeout+0x80/0x80
      [478381.215872]  [<ffffffff8177d47c>] out_of_line_wait_on_bit+0x7c/0x90
      [478381.216806]  [<ffffffff810a89f0>] ? wake_atomic_t_function+0x40/0x40
      [478381.217773]  [<ffffffff811f03aa>] __wait_on_buffer+0x2a/0x30
      [478381.218641]  [<ffffffff8123c557>] ext4_bread+0x57/0x70
      [478381.219425]  [<ffffffff8124498c>] __ext4_read_dirblock+0x3c/0x380
      [478381.220467]  [<ffffffff8124665d>] ext4_dx_find_entry+0x7d/0x170
      [478381.221357]  [<ffffffff8114c49e>] ? find_get_entry+0x1e/0xa0
      [478381.222208]  [<ffffffff81246bd4>] ext4_find_entry+0x484/0x510
      [478381.223090]  [<ffffffff812471a2>] ext4_lookup+0x52/0x160
      [478381.223882]  [<ffffffff811c401d>] lookup_real+0x1d/0x60
      [478381.224675]  [<ffffffff811c4698>] __lookup_hash+0x38/0x50
      [478381.225697]  [<ffffffff817745bd>] lookup_slow+0x45/0xab
      [478381.226941]  [<ffffffff811c690e>] link_path_walk+0x7ae/0x820
      [478381.227880]  [<ffffffff811c6a42>] path_init+0xc2/0x430
      [478381.228677]  [<ffffffff813e6e26>] ? security_file_alloc+0x16/0x20
      [478381.229776]  [<ffffffff811c8c57>] path_openat+0x77/0x620
      [478381.230767]  [<ffffffff81185c6e>] ? page_add_file_rmap+0x2e/0x70
      [478381.232019]  [<ffffffff811cb253>] do_filp_open+0x43/0xa0
      [478381.233016]  [<ffffffff8108c4a9>] ? creds_are_invalid+0x29/0x70
      [478381.234072]  [<ffffffff811c0cb0>] do_open_execat+0x70/0x170
      [478381.235039]  [<ffffffff811c1bf8>] do_execveat_common.isra.36+0x1b8/0x6e0
      [478381.236051]  [<ffffffff811c214c>] do_execve+0x2c/0x30
      [478381.236809]  [<ffffffff811ca392>] ? getname+0x12/0x20
      [478381.237564]  [<ffffffff811c23be>] SyS_execve+0x2e/0x40
      [478381.238338]  [<ffffffff81780a1d>] stub_execve+0x6d/0xa0
      [478381.239126] ------------[ cut here ]------------
      [478381.239915] ------------[ cut here ]------------
      [478381.240606] INFO: task python2.7:1168375 blocked for more than 120 seconds.
      [478381.242673]       Not tainted 4.0.9-38_fbk5_hotfix1_2936_g85409c6 #1
      [478381.243653] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
      [478381.244902] python2.7       D ffff88005cf8fb98     0 1168375 1168248 0x00000080
      [478381.244904]  ffff88005cf8fb98 ffff88016c1f0980 ffffffff81c134c0 ffff88016c1f11a0
      [478381.246023]  ffff88005cf8ffd8 ffff880466cd0cbc ffff88016c1f0980 00000000ffffffff
      [478381.247138]  ffff880466cd0cc0 ffff88005cf8fbb8 ffffffff8177cea7 ffff88005cf8fcc8
      [478381.248252] Call Trace:
      [478381.248630]  [<ffffffff8177cea7>] schedule+0x37/0x90
      [478381.249382]  [<ffffffff8177d08e>] schedule_preempt_disabled+0xe/0x10
      [478381.250465]  [<ffffffff8177e892>] __mutex_lock_slowpath+0x92/0x100
      [478381.251409]  [<ffffffff8177e91b>] mutex_lock+0x1b/0x2f
      [478381.252199]  [<ffffffff817745ae>] lookup_slow+0x36/0xab
      [478381.253023]  [<ffffffff811c690e>] link_path_walk+0x7ae/0x820
      [478381.253877]  [<ffffffff811aeb41>] ? try_charge+0xc1/0x700
      [478381.254690]  [<ffffffff811c6a42>] path_init+0xc2/0x430
      [478381.255525]  [<ffffffff813e6e26>] ? security_file_alloc+0x16/0x20
      [478381.256450]  [<ffffffff811c8c57>] path_openat+0x77/0x620
      [478381.257256]  [<ffffffff8115b2fb>] ? lru_cache_add_active_or_unevictable+0x2b/0xa0
      [478381.258390]  [<ffffffff8117b623>] ? handle_mm_fault+0x13f3/0x1720
      [478381.259309]  [<ffffffff811cb253>] do_filp_open+0x43/0xa0
      [478381.260139]  [<ffffffff811d7ae2>] ? __alloc_fd+0x42/0x120
      [478381.260962]  [<ffffffff811b95ac>] do_sys_open+0x13c/0x230
      [478381.261779]  [<ffffffff81011393>] ? syscall_trace_enter_phase1+0x113/0x170
      [478381.262851]  [<ffffffff811b96c2>] SyS_open+0x22/0x30
      [478381.263598]  [<ffffffff81780532>] system_call_fastpath+0x12/0x17
      [478381.264551] ------------[ cut here ]------------
      [478381.265377] ------------[ cut here ]------------
      Signed-off-by: NJens Axboe <axboe@fb.com>
      Reviewed-by: NJeff Moyer <jmoyer@redhat.com>
      b8269db4
  13. 09 6月, 2016 2 次提交
  14. 08 6月, 2016 6 次提交