[LU-1777] open-by-fid: deadlock in lock_rename()

• Type: Bug
• Resolution: Unresolved
• Priority: Minor
• Affects Version/s: Lustre 2.4.0
• Labels: open-by-fid
• Environment: # uanme -r; 2.6.32-279.5.1.el6.x86_64; # cat /proc/fs/lustre/version ; lustre: 2.2.93; kernel: patchless_client; build: 2.2.93-gbaaf628-PRISTINE-2.6.32-279.5.1.el6.x86_64
• Severity: 3
• Assignee: WC Triage
• Reporter: John Hammond

Description

[root]# /usr/src/lustre-release/lustre/tests/llmount.sh
[root]# cd /mnt/lustre/
[root]# mkdir sanity
[root]# chown sanity: sanity
[root]# su sanity
[sanity]$ pwd
/mnt/lustre
[sanity]$ sys_path2fid .
[0x61ab:0xef3d87c8:0x0]
[sanity]$ sys_rename sanity .lustre/fid/[0x61ab:0xef3d87c8:0x0]/sanity

rename() wedges in lock_rename().

INFO: task sys_rename:2960 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
sys_rename    D 0000000000000000     0  2960   2933 0x00000080
 ffff88005cc37cf8 0000000000000082 ffff88005cc37d08 ffffffff81189a05
 0000001000000000 ffff88007b01cb70 ffffffff8100bc0e ffff88005cc37cf8
 ffff880062a67098 ffff88005cc37fd8 000000000000fb88 ffff880062a67098
Call Trace:
 [<ffffffff81189a05>] ? __link_path_walk+0x155/0x1030
 [<ffffffff8100bc0e>] ? apic_timer_interrupt+0xe/0x20
 [<ffffffff8104f18b>] ? mutex_spin_on_owner+0x9b/0xc0
 [<ffffffff814ff2fe>] __mutex_lock_slowpath+0x13e/0x180
 [<ffffffff814ff19b>] mutex_lock+0x2b/0x50
 [<ffffffff811878e3>] lock_rename+0x73/0xe0
 [<ffffffff8118af83>] sys_renameat+0x113/0x260
 [<ffffffff8119a470>] ? mntput_no_expire+0x30/0x110
 [<ffffffff8117cb11>] ? __fput+0x1a1/0x210
 [<ffffffff81142c7e>] ? remove_vma+0x6e/0x90
 [<ffffffff810d6b12>] ? audit_syscall_entry+0x272/0x2a0
 [<ffffffff815036de>] ? do_page_fault+0x3e/0xa0
 [<ffffffff8118b0eb>] sys_rename+0x1b/0x20
 [<ffffffff8100b0f2>] system_call_fastpath+0x16/0x1b

[root]# pidof sys_rename
2960
[root]# cat /proc/2960/stack
[<ffffffff811878e3>] lock_rename+0x73/0xe0
[<ffffffff8118af83>] sys_renameat+0x113/0x260
[<ffffffff8118b0eb>] sys_rename+0x1b/0x20
[<ffffffff8100b0f2>] system_call_fastpath+0x16/0x1b
[<ffffffffffffffff>] 0xffffffffffffffff

Issue Links

• is related to: LU-1518 Missing/bad operations in mdd_{obf,dot_lustre}_obj_op causing LBUGs