syzbot


INFO: task hung in nilfs_fiemap

Status: auto-obsoleted due to no activity on 2024/11/20 18:42
Subsystems: nilfs
[Documentation on labels]
First crash: 170d, last: 170d

Sample crash report:
INFO: task syz.3.22:5457 blocked for more than 143 seconds.
      Not tainted 6.11.0-rc4-syzkaller-00033-g872cf28b8df9 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.22        state:D stack:27096 pid:5457  tgid:5449  ppid:5234   flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678
 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178
 __down_write_common kernel/locking/rwsem.c:1306 [inline]
 __down_write kernel/locking/rwsem.c:1315 [inline]
 down_write+0x1d7/0x220 kernel/locking/rwsem.c:1580
 inode_lock include/linux/fs.h:799 [inline]
 nilfs_fiemap+0x1d2/0xb10 fs/nilfs2/inode.c:1175
 ioctl_fiemap fs/ioctl.c:220 [inline]
 do_vfs_ioctl+0x1c07/0x2e50 fs/ioctl.c:841
 __do_sys_ioctl fs/ioctl.c:905 [inline]
 __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0f94579e79
RSP: 002b:00007f0f953ff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f0f94716130 RCX: 00007f0f94579e79
RDX: 0000000020000080 RSI: 00000000c020660b RDI: 0000000000000007
RBP: 00007f0f945e7916 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f0f94716130 R15: 00007fff6768b1a8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
 #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626
3 locks held by kworker/u8:6/975:
2 locks held by getty/4974:
 #0: ffff88802b80d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211
2 locks held by syz.3.22/5456:
1 lock held by syz.3.22/5457:
 #0: ffff888079e2af40 (&type->i_mutex_dir_key#17){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:799 [inline]
 #0: ffff888079e2af40 (&type->i_mutex_dir_key#17){+.+.}-{3:3}, at: nilfs_fiemap+0x1d2/0xb10 fs/nilfs2/inode.c:1175
1 lock held by syz.0.285/7523:
1 lock held by syz.1.286/7527:
 #0: ffffffff8e73d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:296 [inline]
 #0: ffffffff8e73d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:958
2 locks held by syz.4.284/7532:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc4-syzkaller-00033-g872cf28b8df9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
 watchdog+0xff4/0x1040 kernel/hung_task.c:379
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7532 Comm: syz.4.284 Not tainted 6.11.0-rc4-syzkaller-00033-g872cf28b8df9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:generic_perform_write+0x294/0x840 mm/filemap.c:4009
Code: e8 b1 29 2c 00 4c 8b 2b 4c 8b 64 24 20 49 8d 44 24 ff 48 23 44 24 08 49 29 c4 4d 39 ec 4d 0f 43 e5 48 8b 3c 24 e8 6c ab 01 00 <4c> 89 ff 4c 89 e6 e8 81 6b da 02 48 89 c3 48 89 c7 4c 89 e6 e8 f3
RSP: 0018:ffffc9000307fb20 EFLAGS: 00000286
RAX: 0000000000000000 RBX: ffffc9000307fd88 RCX: 0000000000040000
RDX: ffffc9001548a000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: ffffc9000307fc60 R08: ffffffff81cd04e6 R09: 1ffffd40002bf706
R10: dffffc0000000000 R11: fffff940002bf707 R12: 0000000000037000
R13: 0000000000237000 R14: dffffc0000000000 R15: ffffc9000307fd70
FS:  00007fbd2cbe46c0(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f103f861870 CR3: 000000007ed6a000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 shmem_file_write_iter+0xfc/0x120 mm/shmem.c:3074
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0xa72/0xc90 fs/read_write.c:590
 ksys_write+0x1a0/0x2c0 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbd2bd7895f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 c9 8d 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 1c 8e 02 00 48
RSP: 002b:00007fbd2cbe3df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fbd2bd7895f
RDX: 0000000001000000 RSI: 00007fbd21400000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000051a4
R10: 0000000020005282 R11: 0000000000000293 R12: 0000000000000003
R13: 00007fbd2cbe3ef0 R14: 00007fbd2cbe3eb0 R15: 00007fbd21400000
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/22 18:31 upstream 872cf28b8df9 ca02180f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in nilfs_fiemap
* Struck through repros no longer work on HEAD.