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INFO: task hung in fuse_lookup

Status: upstream: reported C repro on 2019/08/14 05:24
Subsystems: reiserfs
[Documentation on labels]
Reported-by: syzbot+f8b3822507e83905193d@syzkaller.appspotmail.com
First crash: 1926d, last: 648d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 INFO: task hung in fuse_lookup 4 1877d 2030d 0/1 auto-closed as invalid on 2020/01/29 21:30
linux-4.14 INFO: task hung in fuse_lookup (3) 1 1041d 1041d 0/1 auto-closed as invalid on 2022/05/15 00:47
linux-6.1 INFO: task hung in fuse_lookup origin:upstream syz error 3 233d 533d 0/3 upstream: reported syz repro on 2023/06/07 05:32
upstream INFO: task hung in fuse_lookup (3) fuse C done error 46 6d03h 1925d 0/28 upstream: reported C repro on 2019/08/14 09:48
linux-5.15 INFO: task hung in fuse_lookup origin:upstream syz error 2 50d 533d 0/3 upstream: reported syz repro on 2023/06/07 02:49
linux-4.14 INFO: task hung in fuse_lookup (4) reiserfs C 2 653d 708d 0/1 upstream: reported C repro on 2022/12/13 09:09
linux-4.14 INFO: task hung in fuse_lookup (2) 1 1711d 1711d 0/1 auto-closed as invalid on 2020/07/13 23:30
upstream INFO: task hung in fuse_lookup fuse 16 2270d 2321d 0/28 closed as invalid on 2018/09/05 12:51
android-49 INFO: task hung in fuse_lookup C 112 1839d 2051d 0/3 public: reported C repro on 2019/04/11 08:44
upstream INFO: task hung in fuse_lookup (2) fuse C 13 2104d 2264d 0/28 closed as dup on 2018/09/10 08:43
▶ ▼ Fix bisection attempts (5)
Created Duration User Patch Repo Result
2020/04/15 22:08 22m bisect fix linux-4.19.y error job log
2020/03/12 00:12 40m bisect fix linux-4.19.y OK (0) job log log
2020/02/10 21:10 39m bisect fix linux-4.19.y OK (0) job log log
2020/01/11 20:31 39m bisect fix linux-4.19.y OK (0) job log log
2019/12/12 18:32 39m bisect fix linux-4.19.y OK (0) job log log

Sample crash report:
IPVS: ftp: loaded support on port[0] = 21
INFO: task syz-executor311:8122 blocked for more than 140 seconds.
      Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor311 D27536  8122   8121 0x00000000
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1016 [inline]
 __mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
 fuse_lock_inode+0xaf/0xe0 fs/fuse/inode.c:365
 fuse_lookup+0x86/0x410 fs/fuse/dir.c:367
 __lookup_slow+0x246/0x4a0 fs/namei.c:1672
 lookup_slow fs/namei.c:1689 [inline]
 walk_component+0x7ac/0xda0 fs/namei.c:1811
 link_path_walk.part.0+0x901/0x1230 fs/namei.c:2142
 link_path_walk fs/namei.c:2073 [inline]
 path_openat+0x1db/0x2df0 fs/namei.c:3536
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 do_sys_open+0x3b3/0x520 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fe6a33aae58
Code: Bad RIP value.
RSP: 002b:00007ffc1c34a740 EFLAGS: 00000287 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ffc1c34a7b0 RCX: 00007fe6a33aae58
RDX: 0000000000090800 RSI: 00007fe6a3401004 RDI: 00000000ffffff9c
RBP: 0000000000000002 R08: 0000000000090800 R09: 00007fe6a3401004
R10: 0000000000000000 R11: 0000000000000287 R12: 00007ffc1c34a93c
R13: 0000000000000002 R14: 00007ffc1c34a990 R15: 00007ffc1c34a980
INFO: task syz-executor311:8148 blocked for more than 140 seconds.
      Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor311 D27528  8148   8122 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 request_wait_answer+0x3dc/0x750 fs/fuse/dev.c:485
 __fuse_request_send+0x123/0x1c0 fs/fuse/dev.c:505
 fuse_simple_request+0x2e6/0x820 fs/fuse/dev.c:576
 fuse_lookup_name+0x24c/0x5c0 fs/fuse/dir.c:330
 fuse_lookup+0xdf/0x410 fs/fuse/dir.c:368
 __lookup_slow+0x246/0x4a0 fs/namei.c:1672
 lookup_slow fs/namei.c:1689 [inline]
 walk_component+0x7ac/0xda0 fs/namei.c:1811
 link_path_walk.part.0+0x901/0x1230 fs/namei.c:2142
 link_path_walk fs/namei.c:2270 [inline]
 path_lookupat+0xe4/0x8d0 fs/namei.c:2318
 do_o_path fs/namei.c:3511 [inline]
 path_openat+0x1f92/0x2df0 fs/namei.c:3533
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 do_sys_open+0x3b3/0x520 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fe6a33ab1c9
Code: Bad RIP value.
RSP: 002b:00007fe6a333b2f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fe6a34344d0 RCX: 00007fe6a33ab1c9
RDX: 0000000000200000 RSI: 0000000020000340 RDI: ffffffffffffff9c
RBP: 00007fe6a34011bc R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e
R13: 65646f6d746f6f72 R14: 6873612f7665642f R15: 00007fe6a34344d8

Showing all locks held in the system:
1 lock held by ksoftirqd/0/9:
 #0: 00000000e500f43e (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1826 [inline]
 #0: 00000000e500f43e (&rq->lock){-.-.}, at: __schedule+0x1f9/0x2040 kernel/sched/core.c:3455
1 lock held by khungtaskd/1570:
 #0: 000000005235cee2 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441
2 locks held by syz-executor311/8122:
 #0: 000000002e4ad9c1 (&type->i_mutex_dir_key#7){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline]
 #0: 000000002e4ad9c1 (&type->i_mutex_dir_key#7){++++}, at: lookup_slow fs/namei.c:1688 [inline]
 #0: 000000002e4ad9c1 (&type->i_mutex_dir_key#7){++++}, at: walk_component+0x798/0xda0 fs/namei.c:1811
 #1: 00000000aca68daf (&fi->mutex){+.+.}, at: fuse_lock_inode+0xaf/0xe0 fs/fuse/inode.c:365
2 locks held by syz-executor311/8148:
 #0: 000000002e4ad9c1 (&type->i_mutex_dir_key#7){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline]
 #0: 000000002e4ad9c1 (&type->i_mutex_dir_key#7){++++}, at: lookup_slow fs/namei.c:1688 [inline]
 #0: 000000002e4ad9c1 (&type->i_mutex_dir_key#7){++++}, at: walk_component+0x798/0xda0 fs/namei.c:1811
 #1: 00000000aca68daf (&fi->mutex){+.+.}, at: fuse_lock_inode+0xaf/0xe0 fs/fuse/inode.c:365

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline]
 watchdog+0x991/0xe60 kernel/hung_task.c:287
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4694 Comm: systemd-journal Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:___bpf_prog_run+0x6e/0x4e80 kernel/bpf/core.c:1065
Code: ff 4c 89 f0 4c 89 f2 48 c1 e8 03 83 e2 07 0f b6 04 18 38 d0 7f 08 84 c0 0f 85 f7 38 00 00 45 0f b6 3e 4a 8d 3c fd 60 b4 6f 88 <4c> 89 fe 48 89 f8 48 c1 e8 03 80 3c 18 00 0f 85 c7 38 00 00 43 ff
RSP: 0018:ffff8880a082fa30 EFLAGS: 00000246
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffff8880a082fe70
RDX: 0000000000000000 RSI: ffffffff816c36e5 RDI: ffffffff886fba00
RBP: ffff8880a082fb00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000000 R12: ffffffff886fb460
R13: ffffed1014105f62 R14: ffffc90001ad4058 R15: 00000000000000b4
FS:  00007fc6658928c0(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc662c6c000 CR3: 00000000a084c000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:

Crashes (12):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/12/07 17:39 linux-4.19.y 3f8a27f9e27b d88f3abb .config console log report syz C [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in fuse_lookup
2019/10/17 16:57 linux-4.19.y dafd634415a7 8c88c9c1 .config console log report syz C ci2-linux-4-19
2019/08/14 04:23 linux-4.19.y 893af1c79e42 ef801a3e .config console log report syz C ci2-linux-4-19
2023/01/12 05:09 linux-4.19.y 3f8a27f9e27b 96166539 .config console log report syz [disk image] [vmlinux] [mounted in repro] ci2-linux-4-19 INFO: task hung in fuse_lookup
2023/02/11 20:26 linux-4.19.y 3f8a27f9e27b 93e26d60 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in fuse_lookup
2022/09/16 09:45 linux-4.19.y 3f8a27f9e27b dd9a85ff .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in fuse_lookup
2022/08/14 00:39 linux-4.19.y 3f8a27f9e27b 8dfcaa3d .config console log report info ci2-linux-4-19 INFO: task hung in fuse_lookup
2022/07/19 15:40 linux-4.19.y 3f8a27f9e27b 72a3cc0c .config console log report info ci2-linux-4-19 INFO: task hung in fuse_lookup
2022/06/19 12:56 linux-4.19.y 3f8a27f9e27b 8f633d84 .config console log report info ci2-linux-4-19 INFO: task hung in fuse_lookup
2022/03/09 02:42 linux-4.19.y 3f8a27f9e27b 9e8eaa75 .config console log report info ci2-linux-4-19 INFO: task hung in fuse_lookup
2020/03/16 22:06 linux-4.19.y 339485c9a80f 749688d2 .config console log report ci2-linux-4-19
2019/10/19 08:51 linux-4.19.y c3038e718a19 8c88c9c1 .config console log report ci2-linux-4-19
* Struck through repros no longer work on HEAD.