syzbot


INFO: task hung in nilfs_segctor_thread

Status: upstream: reported C repro on 2022/11/05 03:06
Subsystems: nilfs2
[Documentation on labels]
Reported-by: syzbot+e07ad170cd11d4d7ef81@syzkaller.appspotmail.com
First crash: 536d, last: 435d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in nilfs_segctor_thread nilfs C error 94 358d 532d 22/26 fixed on 2023/06/08 14:41
linux-5.15 INFO: task hung in nilfs_segctor_thread 3 368d 380d 0/3 auto-obsoleted due to no activity on 2023/08/20 05:29
linux-4.14 INFO: task hung in nilfs_segctor_thread nilfs2 C 1 433d 433d 0/1 upstream: reported C repro on 2023/02/16 07:03
upstream INFO: task hung in nilfs_segctor_thread (2) nilfs 2 61d 65d 0/26 upstream: reported on 2024/02/19 10:54

Sample crash report:
NILFS (loop0): unable to move secondary superblock to block 18446744073709551612
audit: type=1804 audit(1676386495.968:3): pid=8112 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor304" name="/root/file0/bus" dev="loop0" ino=12 res=1
INFO: task segctord:8118 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.
segctord        D26288  8118      2 0x80000000
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+0x4f/0x90 kernel/locking/rwsem.c:72
 nilfs_transaction_lock+0x1fb/0x8b0 fs/nilfs2/segment.c:362
 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2479 [inline]
 nilfs_segctor_thread+0x3c0/0xf50 fs/nilfs2/segment.c:2563
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Showing all locks held in the system:
1 lock held by khungtaskd/1571:
 #0: 000000005bc60963 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441
1 lock held by kswapd0/1969:
1 lock held by in:imklog/7781:
 #0: 00000000d60cbbee (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
4 locks held by syz-executor304/8112:
1 lock held by segctord/8118:
 #0: 0000000090ee38e8 (&nilfs->ns_segctor_sem){++++}, at: nilfs_transaction_lock+0x1fb/0x8b0 fs/nilfs2/segment.c:362

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

NMI backtrace for cpu 0
CPU: 0 PID: 1571 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8112 Comm: syz-executor304 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:784 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:806 [inline]
RIP: 0010:lock_is_held_type+0x82/0x210 kernel/locking/lockdep.c:3942
Code: f1 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 6a 01 00 00 48 83 3d 36 cd a6 08 00 0f 84 1d 01 00 00 9c 58 <0f> 1f 44 00 00 48 ba 00 00 00 00 00 fc ff df 48 89 c3 48 c7 c0 90
RSP: 0018:ffff8880956bf550 EFLAGS: 00000286
RAX: 0000000000000286 RBX: ffff8880b512e200 RCX: 0000000000000001
RDX: dffffc0000000000 RSI: 00000000ffffffff RDI: ffff8880b512ea84
RBP: ffffffff89f85f60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 00000000135a7410 R12: 00000000000001e2
R13: dffffc0000000000 R14: ffff88808e55dc08 R15: ffffea0000428448
FS:  000055555648f300(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005652cee9ce50 CR3: 00000000a51da000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 lock_is_held include/linux/lockdep.h:344 [inline]
 ___might_sleep+0x1ea/0x2b0 kernel/sched/core.c:6157
 lock_page include/linux/pagemap.h:482 [inline]
 pagecache_get_page+0x5f2/0xd50 mm/filemap.c:1577
 find_or_create_page include/linux/pagemap.h:322 [inline]
 grab_cache_page include/linux/pagemap.h:388 [inline]
 nilfs_grab_buffer+0xa5/0x560 fs/nilfs2/page.c:57
 nilfs_mdt_submit_block.constprop.0+0xa8/0xaa0 fs/nilfs2/mdt.c:121
 nilfs_mdt_read_block+0x96/0x3e0 fs/nilfs2/mdt.c:175
 nilfs_mdt_get_block+0xe6/0xd40 fs/nilfs2/mdt.c:250
 nilfs_sufile_get_segment_usage_block fs/nilfs2/sufile.c:92 [inline]
 nilfs_sufile_truncate_range fs/nilfs2/sufile.c:674 [inline]
 nilfs_sufile_resize+0x760/0x1230 fs/nilfs2/sufile.c:772
 nilfs_resize_fs+0x1e4/0xdb0 fs/nilfs2/super.c:423
 nilfs_ioctl_resize fs/nilfs2/ioctl.c:1054 [inline]
 nilfs_ioctl+0x1138/0x1bf0 fs/nilfs2/ioctl.c:1326
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688
 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7ff704870619
Code: Bad RIP value.
RSP: 002b:00007ffd19320f88 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff704870619
RDX: 0000000020000040 RSI: 0000000040086e8b RDI: 0000000000000006
RBP: 0000000000000000 R08: 00007ff7048deec0 R09: 00007ff7048deec0
R10: 00007ff7048deec0 R11: 0000000000000246 R12: 00007ffd19320fb0
R13: 0000000000000000 R14: 431bde82d7b634db R15: 0000000000000000

Crashes (41):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/02/14 15:00 linux-4.19.y 3f8a27f9e27b 93ae7e0a .config console log report syz C [disk image] [vmlinux] [mounted in repro] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2023/01/27 19:21 linux-4.19.y 3f8a27f9e27b 9dfcf09c .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/19 05:56 linux-4.19.y 3f8a27f9e27b 5bb70014 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/18 05:16 linux-4.19.y 3f8a27f9e27b 5bb70014 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/17 15:22 linux-4.19.y 3f8a27f9e27b 4ba8ab94 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/17 13:22 linux-4.19.y 3f8a27f9e27b 3a127a31 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/17 11:52 linux-4.19.y 3f8a27f9e27b 3a127a31 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/17 06:25 linux-4.19.y 3f8a27f9e27b 3a127a31 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/17 05:28 linux-4.19.y 3f8a27f9e27b 3a127a31 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/16 11:49 linux-4.19.y 3f8a27f9e27b 3a127a31 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/15 23:43 linux-4.19.y 3f8a27f9e27b 3a127a31 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/15 19:56 linux-4.19.y 3f8a27f9e27b 97de9cfc .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/14 23:36 linux-4.19.y 3f8a27f9e27b 97de9cfc .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/13 18:52 linux-4.19.y 3f8a27f9e27b 7ba4d859 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/13 11:06 linux-4.19.y 3f8a27f9e27b f42ee5d8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/13 09:56 linux-4.19.y 3f8a27f9e27b f42ee5d8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/13 09:29 linux-4.19.y 3f8a27f9e27b f42ee5d8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/13 09:19 linux-4.19.y 3f8a27f9e27b f42ee5d8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/12 19:33 linux-4.19.y 3f8a27f9e27b f42ee5d8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/12 19:11 linux-4.19.y 3f8a27f9e27b f42ee5d8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/12 18:01 linux-4.19.y 3f8a27f9e27b f42ee5d8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/12 14:18 linux-4.19.y 3f8a27f9e27b f42ee5d8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/12 11:47 linux-4.19.y 3f8a27f9e27b f42ee5d8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/12 09:13 linux-4.19.y 3f8a27f9e27b f42ee5d8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/11 16:48 linux-4.19.y 3f8a27f9e27b f42ee5d8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/11 03:57 linux-4.19.y 3f8a27f9e27b f42ee5d8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/10 03:20 linux-4.19.y 3f8a27f9e27b b2488a87 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/09 02:01 linux-4.19.y 3f8a27f9e27b 5fa28208 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/08 13:30 linux-4.19.y 3f8a27f9e27b 060f945e .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/08 01:42 linux-4.19.y 3f8a27f9e27b 6feb842b .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/07 12:59 linux-4.19.y 3f8a27f9e27b a779b11a .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/07 10:22 linux-4.19.y 3f8a27f9e27b 6d752409 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/07 05:34 linux-4.19.y 3f8a27f9e27b 6d752409 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/06 16:12 linux-4.19.y 3f8a27f9e27b 6d752409 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/05 22:40 linux-4.19.y 3f8a27f9e27b 6d752409 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/05 19:45 linux-4.19.y 3f8a27f9e27b 6d752409 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/05 17:04 linux-4.19.y 3f8a27f9e27b 6d752409 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/05 15:47 linux-4.19.y 3f8a27f9e27b 6d752409 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/05 08:57 linux-4.19.y 3f8a27f9e27b 6d752409 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/05 07:56 linux-4.19.y 3f8a27f9e27b 6d752409 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
2022/11/05 03:06 linux-4.19.y 3f8a27f9e27b 6d752409 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 INFO: task hung in nilfs_segctor_thread
* Struck through repros no longer work on HEAD.