INFO: task hung in jbd2_journal_commit_transaction

Status: premoderation: reported C repro on 2026/07/31 15:32
Reported-by: syzbot+8e0afc1746ad11c3a57c@syzkaller.appspotmail.com
First crash: 8d16h, last: 20h37m
▶ ▼ Similar bugs (13)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in jbd2_journal_commit_transaction (2) ext4 1 1 1976d 1976d 0/29 auto-closed as invalid on 2021/06/09 10:13
linux-6.6 INFO: task hung in jbd2_journal_commit_transaction (2) 1 6 15h43m 3d09h 0/2 upstream: reported on 2026/08/05 22:06
android-44 INFO: task hung in jbd2_journal_commit_transaction 1 syz, C 6 2962d 2675d 0/2 public: reported C repro on 2019/04/13 00:00
android-49 INFO: task hung in jbd2_journal_commit_transaction 1 5 2869d 3014d 0/3 auto-closed as invalid on 2019/03/29 12:13
upstream INFO: task hung in jbd2_journal_commit_transaction (5) ext4 1 syz, C error error 2286 4h56m 816d 0/29 upstream: reported C repro on 2024/05/15 03:54
linux-6.1 INFO: task hung in jbd2_journal_commit_transaction 1 1 1164d 1164d 0/3 auto-obsoleted due to no activity on 2023/09/09 09:50
linux-5.15 INFO: task hung in jbd2_journal_commit_transaction 1 13 20h43m 4d02h 0/3 upstream: reported on 2026/08/05 05:38
linux-6.1 INFO: task hung in jbd2_journal_commit_transaction (2) origin:lts-only 1 syz inconclusive 15 1d18h 393d 0/3 upstream: reported syz repro on 2025/07/11 16:44
upstream INFO: task hung in jbd2_journal_commit_transaction (4) ext4 1 7 1108d 1256d 0/29 auto-obsoleted due to no activity on 2023/10/25 18:13
upstream INFO: task hung in jbd2_journal_commit_transaction (3) ext4 1 syz, C error error 24 1409d 1694d 0/29 auto-obsoleted due to no activity on 2023/01/27 09:20
upstream INFO: task hung in jbd2_journal_commit_transaction ext4 1 syz, C 52 2856d 2875d 0/29 closed as dup on 2018/10/02 14:53
linux-6.6 INFO: task hung in jbd2_journal_commit_transaction 1 2 307d 394d 0/2 auto-obsoleted due to no activity on 2026/01/13 11:32
android-414 INFO: task hung in jbd2_journal_commit_transaction 1 syz, C 31 2861d 2677d 0/1 public: reported C repro on 2019/04/11 00:00

Sample crash report:
INFO: task jbd2/sda1-8:73 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:jbd2/sda1-8     state:D stack:0     pid:73    tgid:73    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6060 [inline]
 __schedule+0x1496/0x20b0 kernel/sched/core.c:7880
 __schedule_loop kernel/sched/core.c:7957 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7972
 io_schedule+0x88/0xe0 kernel/sched/core.c:8786
 bit_wait_io+0x17/0xd0 kernel/sched/wait_bit.c:209
 __wait_on_bit+0xb3/0x2e0 kernel/sched/wait_bit.c:49
 out_of_line_wait_on_bit+0x139/0x190 kernel/sched/wait_bit.c:64
 wait_on_bit_io include/linux/wait_bit.h:101 [inline]
 __wait_on_buffer+0x5a/0x70 fs/buffer.c:123
 wait_on_buffer include/linux/buffer_head.h:422 [inline]
 jbd2_journal_commit_transaction+0x2dba/0x5510 fs/jbd2/commit.c:814
 kjournald2+0x386/0x6a0 fs/jbd2/journal.c:201
 kthread+0x2c7/0x360 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 4d4a838cf2fc485b043991145ccf8426a0241c16
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
 watchdog+0xe45/0xf90 kernel/hung_task.c:423
 kthread+0x2c7/0x360 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 3170 Comm: syz-executor376 Not tainted syzkaller #0 4d4a838cf2fc485b043991145ccf8426a0241c16
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:rep_stos_alternative+0x43/0x80 arch/x86/lib/clear_page_64.S:97
Code: ff c9 75 f6 e9 ce 79 03 00 48 89 07 48 83 c7 08 83 e9 08 74 ef 83 f9 08 73 ef eb de 66 2e 0f 1f 84 00 00 00 00 00 90 48 89 07 <48> 89 47 08 48 89 47 10 48 89 47 18 48 89 47 20 48 89 47 28 48 89
RSP: 0018:ffffc9000457f958 EFLAGS: 00040202
RAX: 0000000000000000 RBX: 00007ffffffff001 RCX: 0000000000000380
RDX: 0000000000000000 RSI: 0000200000e2d380 RDI: 0000200000e2e000
RBP: ffffc9000457fab0 R08: ffff88810fb89300 R09: 0000000000000006
R10: 0000000000000005 R11: 0000000000000000 R12: 0000200000e2d380
R13: 0000000000001000 R14: 1ffff920008aff3c R15: 0000000000e2c000
FS:  000055556a9b83c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000e2e000 CR3: 00000001214f2000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 read_iter_zero+0x95/0x290 drivers/char/mem.c:480
 do_iter_readv_writev+0x62c/0x820 fs/read_write.c:-1
 vfs_readv+0x301/0xa00 fs/read_write.c:1037
 do_preadv fs/read_write.c:1154 [inline]
 __do_sys_preadv2 fs/read_write.c:1216 [inline]
 __se_sys_preadv2+0x181/0x2a0 fs/read_write.c:1207
 __x64_sys_preadv2+0xc3/0xf0 fs/read_write.c:1207
 x64_sys_call+0x17f1/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:328
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f6a127c2fc9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 d8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc3a1eb558 EFLAGS: 00000246 ORIG_RAX: 0000000000000147
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f6a127c2fc9
RDX: 0000000000000002 RSI: 0000200000001540 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc3a1eb58c
R13: 00007ffc3a1eb5c0 R14: 00007ffc3a1eb5a0 R15: 00000000000002ba
 </TASK>

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/08 11:14 android16-6.12 b54741372957 5d63f80b .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in jbd2_journal_commit_transaction
2026/08/02 05:58 android16-6.12 1a138e24e292 e611ffe1 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in jbd2_journal_commit_transaction
2026/08/01 05:14 android16-6.12 1a138e24e292 e611ffe1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in jbd2_journal_commit_transaction
2026/07/31 15:32 android16-6.12 7d66c8550304 7664cf44 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in jbd2_journal_commit_transaction
2026/08/08 06:11 android16-6.12 b54741372957 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in jbd2_journal_commit_transaction
2026/08/07 17:59 android16-6.12 282da3f968e5 e4ef95d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in jbd2_journal_commit_transaction
2026/08/05 09:53 android16-6.12 f068f96e8cc3 52aa2820 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in jbd2_journal_commit_transaction
2026/08/05 09:52 android16-6.12 f068f96e8cc3 52aa2820 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in jbd2_journal_commit_transaction
* Struck through repros no longer work on HEAD.