syzbot


INFO: task hung in exfat_write_inode

Status: upstream: reported C repro on 2022/12/22 18:53
Subsystems: exfat
[Documentation on labels]
Reported-by: syzbot+2f73ed585f115e98aee8@syzkaller.appspotmail.com
First crash: 437d, last: 5d15h
Cause bisection: introduced by (bisect log) :
commit 907fa893258ba6076f5fff32900a461decb9e8c5
Author: Namjae Jeon <namjae.jeon@samsung.com>
Date: Thu May 21 23:10:10 2020 +0000

  exfat: add the dummy mount options to be backward compatible with staging/exfat

Crash: BUG: unable to handle kernel NULL pointer dereference in exfat_free_cluster (log)
Repro: C syz .config
  
Fix bisection: failed (error log, bisect log)
  
Discussions (6)
Title Replies (including bot) Last reply
[syzbot] [exfat?] INFO: task hung in exfat_write_inode 0 (5) 2023/11/30 08:43
[syzbot] Monthly exfat report (Nov 2023) 2 (3) 2023/11/29 15:48
[syzbot] Monthly exfat report (Oct 2023) 0 (1) 2023/10/25 13:11
[syzbot] Monthly exfat report (Sep 2023) 0 (1) 2023/09/11 08:39
[syzbot] Monthly exfat report (Aug 2023) 0 (1) 2023/08/09 12:33
[syzbot] Monthly fat report 0 (1) 2023/03/30 10:28
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: task hung in exfat_write_inode 3 51d 115d 0/3 upstream: reported on 2023/08/12 04:03
Last patch testing requests (12)
Created Duration User Patch Repo Result
2023/11/30 08:43 17m lizhi.xu@windriver.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git f9ff5644bcc0 report log
2023/11/30 07:55 19m lizhi.xu@windriver.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git f9ff5644bcc0 report log
2023/11/30 07:28 16m lizhi.xu@windriver.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git f9ff5644bcc0 report log
2023/11/30 00:00 30m retest repro upstream report log
2023/11/30 00:00 26m retest repro upstream report log
2023/11/15 22:28 21m retest repro upstream report log
2023/11/15 17:39 53m retest repro linux-next OK log
2023/11/01 06:40 15m retest repro upstream report log
2023/08/25 02:24 20m retest repro upstream report log
2023/08/25 02:24 20m retest repro upstream report log
2023/08/25 02:24 17m retest repro upstream report log
2023/08/25 02:24 21m retest repro linux-next report log
Fix bisection attempts (3)
Created Duration User Patch Repo Result
2023/04/27 19:32 8h03m bisect fix upstream error job log (0)
2023/03/14 23:17 55m bisect fix upstream job log (0) log
2023/01/31 13:51 33m bisect fix upstream job log (0) log
Cause bisection attempts (2)
Created Duration User Patch Repo Result
2023/11/29 14:52 6h49m bisect upstream job log (1) log
2023/01/16 21:52 8h05m bisect upstream error job log (0)
marked invalid by nogikh@google.com

Sample crash report:
INFO: task kworker/u4:0:9 blocked for more than 143 seconds.
      Not tainted 6.5.0-rc3-syzkaller-00123-g57012c57536f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:0    state:D stack:25584 pid:9     ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:5)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0xee1/0x59f0 kernel/sched/core.c:6710
 schedule+0xe7/0x1b0 kernel/sched/core.c:6786
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6845
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x967/0x1340 kernel/locking/mutex.c:747
 exfat_write_inode+0x6c/0x130 fs/exfat/inode.c:93
 write_inode fs/fs-writeback.c:1456 [inline]
 __writeback_single_inode+0xa81/0xe70 fs/fs-writeback.c:1668
 writeback_sb_inodes+0x599/0x1010 fs/fs-writeback.c:1894
 __writeback_inodes_wb+0xff/0x2d0 fs/fs-writeback.c:1965
 wb_writeback+0x7f8/0xa90 fs/fs-writeback.c:2072
 wb_check_background_flush fs/fs-writeback.c:2142 [inline]
 wb_do_writeback fs/fs-writeback.c:2230 [inline]
 wb_workfn+0x874/0xfd0 fs/fs-writeback.c:2257
 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2597
 worker_thread+0x687/0x1110 kernel/workqueue.c:2748
 kthread+0x33a/0x430 kernel/kthread.c:389
 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296
RIP: 0000:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
INFO: task kworker/u4:1:11 blocked for more than 144 seconds.
      Not tainted 6.5.0-rc3-syzkaller-00123-g57012c57536f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:1    state:D stack:25088 pid:11    ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:2)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0xee1/0x59f0 kernel/sched/core.c:6710
 schedule+0xe7/0x1b0 kernel/sched/core.c:6786
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6845
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x967/0x1340 kernel/locking/mutex.c:747
 exfat_write_inode+0x6c/0x130 fs/exfat/inode.c:93
 write_inode fs/fs-writeback.c:1456 [inline]
 __writeback_single_inode+0xa81/0xe70 fs/fs-writeback.c:1668
 writeback_sb_inodes+0x599/0x1010 fs/fs-writeback.c:1894
 __writeback_inodes_wb+0xff/0x2d0 fs/fs-writeback.c:1965
 wb_writeback+0x7f8/0xa90 fs/fs-writeback.c:2072
 wb_check_background_flush fs/fs-writeback.c:2142 [inline]
 wb_do_writeback fs/fs-writeback.c:2230 [inline]
 wb_workfn+0x874/0xfd0 fs/fs-writeback.c:2257
 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2597
 worker_thread+0x687/0x1110 kernel/workqueue.c:2748
 kthread+0x33a/0x430 kernel/kthread.c:389
 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296
RIP: 0000:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
INFO: task kworker/u4:2:40 blocked for more than 145 seconds.
      Not tainted 6.5.0-rc3-syzkaller-00123-g57012c57536f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:2    state:D stack:25328 pid:40    ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:4)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0xee1/0x59f0 kernel/sched/core.c:6710
 schedule+0xe7/0x1b0 kernel/sched/core.c:6786
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6845
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x967/0x1340 kernel/locking/mutex.c:747
 exfat_write_inode+0x6c/0x130 fs/exfat/inode.c:93
 write_inode fs/fs-writeback.c:1456 [inline]
 __writeback_single_inode+0xa81/0xe70 fs/fs-writeback.c:1668
 writeback_sb_inodes+0x599/0x1010 fs/fs-writeback.c:1894
 __writeback_inodes_wb+0xff/0x2d0 fs/fs-writeback.c:1965
 wb_writeback+0x7f8/0xa90 fs/fs-writeback.c:2072
 wb_check_background_flush fs/fs-writeback.c:2142 [inline]
 wb_do_writeback fs/fs-writeback.c:2230 [inline]
 wb_workfn+0x874/0xfd0 fs/fs-writeback.c:2257
 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2597
 worker_thread+0x687/0x1110 kernel/workqueue.c:2748
 kthread+0x33a/0x430 kernel/kthread.c:389
 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296
RIP: 0000:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
INFO: task kworker/u4:3:51 blocked for more than 147 seconds.
      Not tainted 6.5.0-rc3-syzkaller-00123-g57012c57536f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:3    state:D stack:26960 pid:51    ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:3)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0xee1/0x59f0 kernel/sched/core.c:6710
 schedule+0xe7/0x1b0 kernel/sched/core.c:6786
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6845
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x967/0x1340 kernel/locking/mutex.c:747
 exfat_write_inode+0x6c/0x130 fs/exfat/inode.c:93
 write_inode fs/fs-writeback.c:1456 [inline]
 __writeback_single_inode+0xa81/0xe70 fs/fs-writeback.c:1668
 writeback_sb_inodes+0x599/0x1010 fs/fs-writeback.c:1894
 __writeback_inodes_wb+0xff/0x2d0 fs/fs-writeback.c:1965
 wb_writeback+0x7f8/0xa90 fs/fs-writeback.c:2072
 wb_check_background_flush fs/fs-writeback.c:2142 [inline]
 wb_do_writeback fs/fs-writeback.c:2230 [inline]
 wb_workfn+0x874/0xfd0 fs/fs-writeback.c:2257
 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2597
 worker_thread+0x687/0x1110 kernel/workqueue.c:2748
 kthread+0x33a/0x430 kernel/kthread.c:389
 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296
RIP: 0000:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
INFO: task kworker/u4:5:1111 blocked for more than 148 seconds.
      Not tainted 6.5.0-rc3-syzkaller-00123-g57012c57536f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:5    state:D stack:26960 pid:1111  ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:1)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0xee1/0x59f0 kernel/sched/core.c:6710
 schedule+0xe7/0x1b0 kernel/sched/core.c:6786
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6845
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x967/0x1340 kernel/locking/mutex.c:747
 exfat_write_inode+0x6c/0x130 fs/exfat/inode.c:93
 write_inode fs/fs-writeback.c:1456 [inline]
 __writeback_single_inode+0xa81/0xe70 fs/fs-writeback.c:1668
 writeback_sb_inodes+0x599/0x1010 fs/fs-writeback.c:1894
 __writeback_inodes_wb+0xff/0x2d0 fs/fs-writeback.c:1965
 wb_writeback+0x7f8/0xa90 fs/fs-writeback.c:2072
 wb_check_background_flush fs/fs-writeback.c:2142 [inline]
 wb_do_writeback fs/fs-writeback.c:2230 [inline]
 wb_workfn+0x874/0xfd0 fs/fs-writeback.c:2257
 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2597
 worker_thread+0x687/0x1110 kernel/workqueue.c:2748
 kthread+0x33a/0x430 kernel/kthread.c:389
 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296
RIP: 0000:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
INFO: task kworker/u4:6:5031 blocked for more than 149 seconds.
      Not tainted 6.5.0-rc3-syzkaller-00123-g57012c57536f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:6    state:D stack:26960 pid:5031  ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0xee1/0x59f0 kernel/sched/core.c:6710
 schedule+0xe7/0x1b0 kernel/sched/core.c:6786
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6845
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x967/0x1340 kernel/locking/mutex.c:747
 exfat_write_inode+0x6c/0x130 fs/exfat/inode.c:93
 write_inode fs/fs-writeback.c:1456 [inline]
 __writeback_single_inode+0xa81/0xe70 fs/fs-writeback.c:1668
 writeback_sb_inodes+0x599/0x1010 fs/fs-writeback.c:1894
 __writeback_inodes_wb+0xff/0x2d0 fs/fs-writeback.c:1965
 wb_writeback+0x7f8/0xa90 fs/fs-writeback.c:2072
 wb_check_background_flush fs/fs-writeback.c:2142 [inline]
 wb_do_writeback fs/fs-writeback.c:2230 [inline]
 wb_workfn+0x874/0xfd0 fs/fs-writeback.c:2257
 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2597
 worker_thread+0x687/0x1110 kernel/workqueue.c:2748
 kthread+0x33a/0x430 kernel/kthread.c:389
 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296
RIP: 0000:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/u4:0/9:
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:20 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: raw_atomic64_set include/linux/atomic/atomic-arch-fallback.h:2608 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: raw_atomic_long_set include/linux/atomic/atomic-long.h:79 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:3196 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:675 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:702 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x96a/0x16f0 kernel/workqueue.c:2567
 #1: ffffc900002ffd80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x99e/0x16f0 kernel/workqueue.c:2571
 #2: ffff8880796700e0 (&type->s_umount_key#58){.+.+}-{3:3}, at: trylock_super+0x1c/0x100 fs/super.c:413
 #3: ffff8880197000e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x6c/0x130 fs/exfat/inode.c:93
4 locks held by kworker/u4:1/11:
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:20 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: raw_atomic64_set include/linux/atomic/atomic-arch-fallback.h:2608 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: raw_atomic_long_set include/linux/atomic/atomic-long.h:79 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:3196 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:675 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:702 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x96a/0x16f0 kernel/workqueue.c:2567
 #1: ffffc9000031fd80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x99e/0x16f0 kernel/workqueue.c:2571
 #2: ffff888018f080e0 (&type->s_umount_key#58){.+.+}-{3:3}, at: trylock_super+0x1c/0x100 fs/super.c:413
 #3: ffff888019ba80e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x6c/0x130 fs/exfat/inode.c:93
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8c9a2730 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x2c/0xe20 kernel/rcu/tasks.h:522
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8c9a2430 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x2c/0xe20 kernel/rcu/tasks.h:522
1 lock held by khungtaskd/27:
 #0: ffffffff8c9a3340 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x340 kernel/locking/lockdep.c:6615
4 locks held by kworker/u4:2/40:
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:20 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: raw_atomic64_set include/linux/atomic/atomic-arch-fallback.h:2608 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: raw_atomic_long_set include/linux/atomic/atomic-long.h:79 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:3196 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:675 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:702 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x96a/0x16f0 kernel/workqueue.c:2567
 #1: ffffc90000d1fd80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x99e/0x16f0 kernel/workqueue.c:2571
 #2: ffff88801f0140e0 (&type->s_umount_key#58){.+.+}-{3:3}, at: trylock_super+0x1c/0x100 fs/super.c:413
 #3: ffff888079a100e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x6c/0x130 fs/exfat/inode.c:93
4 locks held by kworker/u4:3/51:
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:20 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: raw_atomic64_set include/linux/atomic/atomic-arch-fallback.h:2608 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: raw_atomic_long_set include/linux/atomic/atomic-long.h:79 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:3196 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:675 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:702 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x96a/0x16f0 kernel/workqueue.c:2567
 #1: ffffc90000dcfd80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x99e/0x16f0 kernel/workqueue.c:2571
 #2: ffff88801ebb20e0 (&type->s_umount_key#58){.+.+}-{3:3}, at: trylock_super+0x1c/0x100 fs/super.c:413
 #3: ffff88802cd4e0e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x6c/0x130 fs/exfat/inode.c:93
4 locks held by kworker/u4:5/1111:
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:20 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: raw_atomic64_set include/linux/atomic/atomic-arch-fallback.h:2608 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: raw_atomic_long_set include/linux/atomic/atomic-long.h:79 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:3196 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:675 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:702 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x96a/0x16f0 kernel/workqueue.c:2567
 #1: ffffc900057ffd80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x99e/0x16f0 kernel/workqueue.c:2571
 #2: ffff88807906a0e0 (&type->s_umount_key#58){.+.+}-{3:3}, at: trylock_super+0x1c/0x100 fs/super.c:413
 #3: ffff88801778c0e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x6c/0x130 fs/exfat/inode.c:93
2 locks held by getty/4768:
 #0: ffff88814ba35098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900020382f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfcb/0x1480 drivers/tty/n_tty.c:2187
6 locks held by syz-executor365/5022:
6 locks held by syz-executor365/5023:
6 locks held by syz-executor365/5024:
6 locks held by syz-executor365/5025:
6 locks held by syz-executor365/5026:
6 locks held by syz-executor365/5027:
4 locks held by kworker/u4:6/5031:
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:20 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: raw_atomic64_set include/linux/atomic/atomic-arch-fallback.h:2608 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: raw_atomic_long_set include/linux/atomic/atomic-long.h:79 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:3196 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:675 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:702 [inline]
 #0: ffff8880136eb938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x96a/0x16f0 kernel/workqueue.c:2567
 #1: ffffc9000350fd80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x99e/0x16f0 kernel/workqueue.c:2571
 #2: ffff88807a5340e0 (&type->s_umount_key#58){.+.+}-{3:3}, at: trylock_super+0x1c/0x100 fs/super.c:413
 #3: ffff8880210920e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x6c/0x130 fs/exfat/inode.c:93

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 6.5.0-rc3-syzkaller-00123-g57012c57536f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x277/0x380 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x2ac/0x310 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xf29/0x11b0 kernel/hung_task.c:379
 kthread+0x33a/0x430 kernel/kthread.c:389
 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296
RIP: 0000:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5027 Comm: syz-executor365 Not tainted 6.5.0-rc3-syzkaller-00123-g57012c57536f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x0/0x20 kernel/kcov.c:303
Code: d6 fe ff ff 66 0f 1f 44 00 00 f3 0f 1e fa 48 8b 0c 24 0f b7 d6 0f b7 f7 bf 03 00 00 00 e9 b8 fe ff ff 0f 1f 84 00 00 00 00 00 <f3> 0f 1e fa 48 8b 0c 24 89 f2 89 fe bf 05 00 00 00 e9 9a fe ff ff
RSP: 0018:ffffc900034ff948 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: 000000001f1b0178 RCX: 0000000000000000
RDX: 1ffff1100f4a68c5 RSI: 000000001f1b0178 RDI: 0000000000000001
RBP: ffff888021092000 R08: 0000000000000004 R09: 000000000001f1b0
R10: 000000000001f1b0 R11: 0000000000000000 R12: ffff88807a534000
R13: 0000000000000000 R14: 0000000000000000 R15: 000000000001f1b0
FS:  0000555555d39380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 000000007dc60000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 is_valid_cluster fs/exfat/exfat_fs.h:415 [inline]
 exfat_clear_bitmap+0x79/0x570 fs/exfat/balloc.c:171
 __exfat_free_cluster+0x772/0x9b0 fs/exfat/fatent.c:192
 exfat_free_cluster+0x7a/0x100 fs/exfat/fatent.c:232
 __exfat_truncate+0x62a/0x7c0 fs/exfat/file.c:184
 exfat_evict_inode+0x263/0x340 fs/exfat/inode.c:622
 evict+0x2ed/0x6b0 fs/inode.c:665
 iput_final fs/inode.c:1791 [inline]
 iput.part.0+0x55e/0x7a0 fs/inode.c:1817
 iput+0x5c/0x80 fs/inode.c:1807
 dentry_unlink_inode+0x292/0x430 fs/dcache.c:401
 __dentry_kill+0x3b8/0x640 fs/dcache.c:607
 dentry_kill fs/dcache.c:745 [inline]
 dput+0x703/0xfd0 fs/dcache.c:913
 do_renameat2+0xc4c/0xdc0 fs/namei.c:5011
 __do_sys_rename fs/namei.c:5055 [inline]
 __se_sys_rename fs/namei.c:5053 [inline]
 __x64_sys_rename+0x81/0xa0 fs/namei.c:5053
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fb5a0498259
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 21 18 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:00007ffec688aba8 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb5a0498259
RDX: 00007fb5a0498259 RSI: 0000000020000080 RDI: 0000000020000040
RBP: 0000000000000004 R08: 0000000020000000 R09: 0000000020000000
R10: 00000000000014d3 R11: 0000000000000246 R12: 00007ffec688abf0
R13: 00007ffec688ac30 R14: 0000000000020000 R15: 0000000000000003
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.818 msecs

Crashes (38):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/07/28 04:46 upstream 57012c57536f 92476829 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-selinux-root INFO: task hung in exfat_write_inode
2023/06/06 11:55 upstream f8dba31b0a82 a4ae4f42 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-smack-root INFO: task hung in exfat_write_inode
2022/12/18 21:22 upstream f9ff5644bcc0 05494336 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs INFO: task hung in exfat_write_inode
2022/12/18 18:34 upstream f9ff5644bcc0 05494336 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-smack-root INFO: task hung in exfat_write_inode
2023/02/12 23:13 linux-next 38d2b86a665b 93e26d60 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-linux-next-kasan-gce-root INFO: task hung in exfat_write_inode
2023/10/17 01:53 upstream 58720809f527 342b9c55 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2023/10/08 04:47 upstream b9ddbb0cde2a 5e837c76 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2023/10/07 03:47 upstream 7de25c855b63 ea12a918 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2023/10/05 08:43 upstream ba7d997a2a29 b7d7ff54 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2023/09/28 05:59 upstream 633b47cb009d c2ab1e5d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2023/09/28 03:19 upstream 633b47cb009d 2895a507 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in exfat_write_inode
2023/09/26 16:36 upstream 6465e260f487 0b6a67ac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2023/09/26 10:35 upstream 6465e260f487 0b6a67ac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in exfat_write_inode
2023/09/25 14:13 upstream 6465e260f487 0b6a67ac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2023/09/18 02:45 upstream e789286468a9 0b6a67ac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2023/09/08 19:41 upstream a48fa7efaf11 6654cf89 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2023/09/01 14:29 upstream 99d99825fc07 696ea0d2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2023/07/27 12:51 upstream 0a8db05b571a 41fe1bae .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2023/07/20 16:20 upstream bfa3037d8280 7b630fdb .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in exfat_write_inode
2023/03/28 19:31 upstream 3a93e40326c8 48c74771 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in exfat_write_inode
2023/03/26 12:26 upstream da8e7da11e4b fbf0499a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2023/03/15 15:54 upstream 6015b1aca1a2 18b58603 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2022/12/22 12:30 upstream 0a924817d2ed 9da18ae8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2022/12/22 12:19 upstream 0a924817d2ed 9da18ae8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2022/12/22 06:54 upstream b6bb9676f216 4067838e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2022/12/22 04:52 upstream b6bb9676f216 4067838e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2022/12/21 23:51 upstream b6bb9676f216 4067838e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2022/12/21 14:23 upstream b6bb9676f216 4067838e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2022/12/21 04:13 upstream b6bb9676f216 d3e76707 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in exfat_write_inode
2022/12/21 01:48 upstream b6bb9676f216 d3e76707 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in exfat_write_inode
2022/12/20 09:40 upstream 6feb57c2fd7c d3e76707 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in exfat_write_inode
2022/12/18 07:17 upstream f9ff5644bcc0 05494336 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in exfat_write_inode
2022/12/17 08:13 upstream 77856d911a8c 05494336 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in exfat_write_inode
2022/12/16 15:54 upstream 84e57d292203 05494336 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in exfat_write_inode
2022/12/15 06:06 upstream 6f1f5caed5bf b18f0a64 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in exfat_write_inode
2022/09/23 21:58 upstream bf682942cd26 0042f2b4 .config console log report info [disk image] [vmlinux] ci2-upstream-fs INFO: task hung in exfat_write_inode
2023/10/18 06:16 linux-next 2dac75696c6d 342b9c55 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in exfat_write_inode
2023/10/18 05:44 linux-next 2dac75696c6d 342b9c55 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in exfat_write_inode
* Struck through repros no longer work on HEAD.