Bug #19688: Kernel panic on CephFS kernel client when setting file ACL - Linux kernel client - Ceph

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Bug #19688

closed

Kernel panic on CephFS kernel client when setting file ACL

Added by Zheng Yan about 7 years ago. Updated almost 7 years ago.

Status:

Resolved

Priority:

Normal

Assignee:

Category:

fs/ceph

Target version:

% Done:

Source:

Tags:

Backport:

Regression:

Severity:

3 - minor

Reviewed:

Affected Versions:

ceph-qa-suite:

Crash signature (v1):

Crash signature (v2):

Description

From: Jerry Lee <leisurelysw24@gmail.com>

Hi,

With the following operations on a CephFS, a kernel panic can be
triggered easily.  It seems that updating the file attribute via
__ceph_setattr() in ceph_set_acl() might race with another
ceph_setattr() operation which results in the file attribute bounces
back and forward.  Under such condition, the call stack is overran and
kernel crashes.  Is it right?  Thanks for any idea and feedback in
advance.

environment:
=========
linux-4.8.4
ceph version v11.0.2

commands:
=========
1) mount -t ceph x.x.x.x:/ /mnt/cephfs -o name=admin,secret=xxxx
2) setfacl -b /mnt/cephfs/
    setfacl -m u:0:rwx,g:0:rwx /mnt/cephfs/
    setfacl -dm u:0:rwx,g:0:rwx /mnt/cephfs/
    setfacl -b /mnt/cephfs/

call traces:
========
<1>[344341.767823] BUG: unable to handle kernel paging request at
fffffffb8a5707a8
<1>[344341.767826] IP: [<ffffffff810aff73>] cpuacct_charge+0x23/0x40
<4>[344341.767830] PGD 1f21067 PUD 0
<0>[344341.767831] Thread overran stack, or stack corrupted
<4>[344341.767832] Oops: 0000 [#1] SMP
<4>[344341.767872] Call Trace:
<4>[344341.767875]  [<ffffffff810a1add>] update_curr+0xcd/0x130
<4>[344341.767876]  [<ffffffff810a35ed>] enqueue_entity+0x3d/0xb40
<4>[344341.767878]  [<ffffffff810a4153>] enqueue_task_fair+0x63/0x7d0
<4>[344341.767879]  [<ffffffff8109f4b4>] ? sched_clock_cpu+0x94/0xa0
<4>[344341.767881]  [<ffffffff8109657e>] enqueue_task+0x2e/0x70
<4>[344341.767883]  [<ffffffff81099b2b>] activate_task+0x2b/0x30
<4>[344341.767884]  [<ffffffff81099e03>]
ttwu_do_activate.constprop.108+0x33/0x70
<4>[344341.767886]  [<ffffffff8109a74d>] try_to_wake_up+0x22d/0x2f0
<4>[344341.767887]  [<ffffffff8109a837>] wake_up_process+0x27/0x50
<4>[344341.767891]  [<ffffffff81b40975>] ? _cond_resched+0x5/0x30
<4>[344341.767894]  [<ffffffff81088a24>] wake_up_worker+0x24/0x30
<4>[344341.767895]  [<ffffffff8108a93e>] insert_work+0x6e/0xb0
<4>[344341.767896]  [<ffffffff81b40975>] ? _cond_resched+0x5/0x30
<4>[344341.767899]  [<ffffffff8117fb4b>] ? kmem_cache_alloc+0x55b/0x690
<4>[344341.767900]  [<ffffffff8108aaae>] __queue_work+0x12e/0x2f0
<4>[344341.767902]  [<ffffffff8108b21e>] __queue_delayed_work+0x8e/0x140
<4>[344341.767903]  [<ffffffff8108b2ed>] queue_delayed_work_on+0x1d/0x30
<4>[344341.767907]  [<ffffffffa08e266e>] queue_con_delay+0x3e/0xf0 [libceph]
<4>[344341.767909]  [<ffffffffa08e3c2a>] ceph_con_send+0xfa/0x1f0 [libceph]
<4>[344341.767912]  [<ffffffffa0940360>] __do_request+0x200/0x2f0 [ceph]
<4>[344341.767914]  [<ffffffffa094159d>] ceph_mdsc_do_request+0x9d/0x2a0 [ceph]
<4>[344341.767916]  [<ffffffffa0925888>] __ceph_do_getattr+0xa8/0x1c0 [ceph]
<4>[344341.767919]  [<ffffffffa093bd56>] __ceph_getxattr+0xa6/0x190 [ceph]
<4>[344341.767921]  [<ffffffffa094657c>] ceph_get_acl+0x4c/0x150 [ceph]
<4>[344341.767923]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.767925]  [<ffffffff811efbb4>] get_acl+0x44/0x60
<4>[344341.767926]  [<ffffffff811eff00>] posix_acl_chmod+0x40/0xd0
<4>[344341.767928]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.767929]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.767931]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.767934]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.767935]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.767936]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.767938]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.767940]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.767941]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.767942]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.767944]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.767945]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.767947]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.767949]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.767950]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.767951]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.767953]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.767954]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.767956]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.767957]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.767958]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.767961]  [<ffffffff811ef741>] ? posix_acl_alloc+0x21/0x40
<4>[344341.767962]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.767964]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.767965]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.767966]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.767968]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.767970]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.767971]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.767973]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.767974]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.767975]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.767977]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.767979]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.767980]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.767981]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.767983]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.767984]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.767986]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.767987]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.767988]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.767990]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.767991]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.767993]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.767995]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.767996]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.767997]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.767999]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768000]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768002]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768003]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768004]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768006]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768008]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768009]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768010]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768012]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768013]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768015]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768016]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768017]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768019]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768020]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768022]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768024]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768025]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768026]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768028]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768029]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768031]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768032]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768033]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768035]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768037]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768038]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768039]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768041]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768042]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768044]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768045]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768046]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768048]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768049]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768051]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768052]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768053]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768055]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768056]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768058]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768059]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768060]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768062]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768063]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768065]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768067]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768068]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768069]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768071]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768072]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768074]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768075]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768076]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768078]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768079]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768081]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768082]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768083]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768085]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768087]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768088]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768089]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768090]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768092]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768094]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768095]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768096]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768098]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768099]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768101]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768102]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768103]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768105]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768106]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768108]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768109]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768110]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768112]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768114]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768115]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768117]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768118]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768119]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768121]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768122]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768124]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768125]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768126]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768128]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768130]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768131]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768132]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768133]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768135]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768137]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768138]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768139]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768141]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768142]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768144]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768145]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768147]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768149]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768151]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768163]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768164]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768165]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768167]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768169]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768170]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768172]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768173]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768174]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768176]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768178]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768189]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768190]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768192]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768193]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768195]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768196]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768197]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768199]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768201]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768202]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768204]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768205]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768206]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768208]  [<ffffffff81b43e95>] ? _raw_spin_lock+0x5/0x30
<4>[344341.768210]  [<ffffffffa0946789>] ceph_set_acl+0x109/0x250 [ceph]
<4>[344341.768211]  [<ffffffff810c8fca>] ? kfree_call_rcu+0x1a/0x20
<4>[344341.768212]  [<ffffffff811eff62>] posix_acl_chmod+0xa2/0xd0
<4>[344341.768214]  [<ffffffffa0925228>] ceph_setattr+0x3a8/0x960 [ceph]
<4>[344341.768215]  [<ffffffff8119bbbb>] ? putname+0x5b/0x60
<4>[344341.768217]  [<ffffffff811aeb31>] notify_change+0x1e1/0x340
<4>[344341.768219]  [<ffffffff8118d723>] chmod_common+0xb3/0x130
<4>[344341.768221]  [<ffffffff8118e96a>] SyS_chmod+0x4a/0xb0
<4>[344341.768223]  [<ffffffff81b441d7>] entry_SYSCALL_64_fastpath+0x12/0x6a
<4>[344341.768223] Code: 0f 1f 84 00 00 00 00 00 e8 bb 66 a9 00 48 8b
47 08 55 48 89 e5 48 63 48 10 48 8b 87 a0 06 00 00 48 8b 50 60 48 8b
82 b0 00 00 00 <48> 03 04 cd c0 30 06 82 48 01 30 48 8b 52 48 48 85 d2
75 e5 5d
<1>[344341.768236] RIP  [<ffffffff810aff73>] cpuacct_charge+0x23/0x40
<4>[344341.768237]  RSP <ffff88041db38008>
<4>[344341.768238] CR2: fffffffb8a5707a8
<4>[344341.768239] ---[ end trace 6c9d7c6b7c9430e7 ]---
<1>[344342.248810] BUG: unable to handle kernel paging request at
fffffffffffffff6
<1>[344342.248812] IP: [<ffffffff8108e4de>] find_pid_ns+0x5e/0x80
<4>[344342.248817] PGD 1f21067 PUD 1f23067 PMD 0
<4>[344342.248818] Oops: 0000 [#2] SMP