syzbot


INFO: task hung in do_unlinkat (2)

Status: auto-obsoleted due to no activity on 2023/03/27 07:50
Reported-by: syzbot+2cf2f6061d1e2d68dd39@syzkaller.appspotmail.com
First crash: 593d, last: 593d
Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-49 INFO: task hung in do_unlinkat 5 2145d 2257d 0/3 auto-closed as invalid on 2019/02/24 11:49
upstream INFO: task hung in do_unlinkat (5) kernfs bcachefs 50 19d 40d 0/27 upstream: reported on 2024/06/02 14:09
upstream INFO: task hung in do_unlinkat (2) fs 4 1251d 1251d 0/27 auto-closed as invalid on 2021/05/17 08:41
upstream INFO: task hung in do_unlinkat exfat 34 2005d 2242d 0/27 closed as dup on 2018/10/27 13:26
upstream INFO: task hung in do_unlinkat (3) fs 2 969d 1013d 0/27 closed as invalid on 2022/02/07 19:19
linux-4.19 INFO: task hung in do_unlinkat 1 723d 723d 0/1 auto-obsoleted due to no activity on 2022/11/17 10:56
upstream INFO: task hung in do_unlinkat (4) exfat 4 562d 668d 0/27 auto-obsoleted due to no activity on 2023/04/08 02:53
linux-5.15 INFO: task hung in do_unlinkat 1 61d 61d 0/3 upstream: reported on 2024/05/12 15:06

Sample crash report:
F2FS-fs (loop1): Inconsistent segment (6) type [1, 0] in SSA and SIT
F2FS-fs (loop1): Inconsistent segment (6) type [1, 0] in SSA and SIT
F2FS-fs (loop1): Inconsistent segment (6) type [1, 0] in SSA and SIT
F2FS-fs (loop1): Inconsistent segment (6) type [1, 0] in SSA and SIT
INFO: task syz-executor.1:13307 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-executor.1  D29432 13307   8171 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
 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline]
 rwsem_down_write_failed+0x3aa/0x760 kernel/locking/rwsem-xadd.c:618
 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:117
 __down_write arch/x86/include/asm/rwsem.h:142 [inline]
 down_write_nested+0x51/0x90 kernel/locking/rwsem.c:194
 inode_lock_nested include/linux/fs.h:783 [inline]
 do_unlinkat+0x27d/0x660 fs/namei.c:4051
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fefd26590d9
Code: Bad RIP value.
RSP: 002b:00007fefcc7aa168 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007fefd2779050 RCX: 00007fefd26590d9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000100
RBP: 00007fefd26b4ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe921a8f5f R14: 00007fefcc7aa300 R15: 0000000000022000

Showing all locks held in the system:
4 locks held by kworker/u4:0/7:
 #0: 0000000088634d06 ((wq_completion)"writeback"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124
 #1: 000000000b81f4eb ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128
 #2: 000000001731fa25 (&type->s_umount_key#48){++++}, at: trylock_super+0x1d/0x100 fs/super.c:412
 #3: 000000008d643565 (&sbi->gc_mutex){+.+.}, at: f2fs_balance_fs+0x709/0xd80 fs/f2fs/segment.c:512
1 lock held by khungtaskd/1569:
 #0: 0000000093dae260 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441
1 lock held by in:imklog/7798:
 #0: 00000000f70940c9 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
3 locks held by syz-executor.1/13268:
2 locks held by syz-executor.1/13307:
 #0: 00000000981cbb5d (sb_writers#14){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline]
 #0: 00000000981cbb5d (sb_writers#14){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360
 #1: 00000000d133fb3f (&type->i_mutex_dir_key#8/1){+.+.}, at: inode_lock_nested include/linux/fs.h:783 [inline]
 #1: 00000000d133fb3f (&type->i_mutex_dir_key#8/1){+.+.}, at: do_unlinkat+0x27d/0x660 fs/namei.c:4051
2 locks held by syz-executor.1/14864:
 #0: 000000001731fa25 (&type->s_umount_key#48){++++}, at: iterate_supers+0xdb/0x290 fs/super.c:631
 #1: 000000007427d353 (&bdi->wb_switch_rwsem){+.+.}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline]
 #1: 000000007427d353 (&bdi->wb_switch_rwsem){+.+.}, at: sync_inodes_sb+0x180/0x9a0 fs/fs-writeback.c:2457
2 locks held by syz-executor.1/14878:
 #0: 000000001731fa25 (&type->s_umount_key#48){++++}, at: iterate_supers+0xdb/0x290 fs/super.c:631
 #1: 000000007427d353 (&bdi->wb_switch_rwsem){+.+.}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline]
 #1: 000000007427d353 (&bdi->wb_switch_rwsem){+.+.}, at: sync_inodes_sb+0x180/0x9a0 fs/fs-writeback.c:2457
2 locks held by syz-executor.1/14883:
 #0: 000000001731fa25 (&type->s_umount_key#48){++++}, at: iterate_supers+0xdb/0x290 fs/super.c:631
 #1: 000000007427d353 (&bdi->wb_switch_rwsem){+.+.}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline]
 #1: 000000007427d353 (&bdi->wb_switch_rwsem){+.+.}, at: sync_inodes_sb+0x180/0x9a0 fs/fs-writeback.c:2457

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

NMI backtrace for cpu 1
CPU: 1 PID: 1569 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: 13268 Comm: syz-executor.1 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:__lock_is_held+0xb1/0x160 kernel/locking/lockdep.c:3726
Code: d2 0f 85 b5 00 00 00 66 f7 43 22 f0 ff 74 0f 4c 89 f6 48 89 df e8 af f7 ff ff 85 c0 75 2f 83 c5 01 41 39 af 80 08 00 00 7e 70 <48> 63 c5 48 8d 04 80 49 8d 1c c4 48 8d 7b 10 48 89 f8 48 c1 e8 03
RSP: 0018:ffff8880925bf320 EFLAGS: 00000002
RAX: 0000000000000003 RBX: ffff88808b644cb0 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffff88808b644cd2
RBP: 0000000000000002 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88808b644c88
R13: dffffc0000000000 R14: ffffffff89f85f60 R15: ffff88808b644400
FS:  00007fefd0bcb700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcebd494000 CR3: 00000000ab726000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 lock_is_held_type+0x10d/0x210 kernel/locking/lockdep.c:3946
 lock_is_held include/linux/lockdep.h:344 [inline]
 ___might_sleep+0x1ea/0x2b0 kernel/sched/core.c:6157
 down_write+0x18/0x90 kernel/locking/rwsem.c:69
 __f2fs_submit_merged_write fs/f2fs/data.c:388 [inline]
 __submit_merged_write_cond+0xbb/0x610 fs/f2fs/data.c:413
 do_garbage_collect fs/f2fs/gc.c:1123 [inline]
 f2fs_gc+0x5e2b/0x8c90 fs/f2fs/gc.c:1196
 f2fs_balance_fs+0x71a/0xd80 fs/f2fs/segment.c:513
 f2fs_create+0x44d/0x930 fs/f2fs/namei.c:307
 lookup_open+0x893/0x1a20 fs/namei.c:3235
 do_last fs/namei.c:3327 [inline]
 path_openat+0x1094/0x2df0 fs/namei.c:3537
 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: 0033:0x7fefd26590d9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fefd0bcb168 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fefd2778f80 RCX: 00007fefd26590d9
RDX: 0000000000000000 RSI: 0000000000143142 RDI: 0000000020002000
RBP: 00007fefd26b4ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe921a8f5f R14: 00007fefd0bcb300 R15: 0000000000022000

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/11/27 07:50 linux-4.19.y 3f8a27f9e27b f4470a7b .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in do_unlinkat
* Struck through repros no longer work on HEAD.