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INFO: task hung in bch2_read_iter (2)

Status: auto-obsoleted due to no activity on 2025/11/15 05:24
Subsystems: fs
[Documentation on labels]
First crash: 176d, last: 176d
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in bch2_read_iter fs 1 109 394d 503d 0/29 auto-obsoleted due to no activity on 2025/03/21 11:55

Sample crash report:
INFO: task syz.5.415:9102 blocked for more than 143 seconds.
      Tainted: G        W           6.17.0-rc1-syzkaller-00211-g90d970cade8e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.415       state:D stack:19720 pid:9102  tgid:9081  ppid:6460   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 __bch2_two_state_lock+0x1ea/0x370 fs/bcachefs/two_state_shared_lock.c:7
 bch2_two_state_lock fs/bcachefs/two_state_shared_lock.h:55 [inline]
 bch2_read_iter+0x213/0x1450 fs/bcachefs/fs-io-direct.c:221
 __kernel_read+0x4d5/0x970 fs/read_write.c:530
 integrity_kernel_read+0x89/0xd0 security/integrity/iint.c:28
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:480 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:511 [inline]
 ima_calc_file_hash+0x86a/0x1700 security/integrity/ima/ima_crypto.c:568
 ima_collect_measurement+0x42e/0x8e0 security/integrity/ima/ima_api.c:293
 process_measurement+0x112d/0x1a40 security/integrity/ima/ima_main.c:405
 ima_file_check+0xd7/0x120 security/integrity/ima/ima_main.c:633
 security_file_post_open+0xbb/0x290 security/security.c:3160
 do_open fs/namei.c:3889 [inline]
 path_openat+0x2f32/0x3840 fs/namei.c:4046
 do_filp_open+0x1fa/0x410 fs/namei.c:4073
 do_sys_openat2+0x121/0x1c0 fs/open.c:1435
 do_sys_open fs/open.c:1450 [inline]
 __do_sys_openat fs/open.c:1466 [inline]
 __se_sys_openat fs/open.c:1461 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1461
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc64313ebe9
RSP: 002b:00007fc641385038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fc643366090 RCX: 00007fc64313ebe9
RDX: 0000000000028040 RSI: 0000200000000280 RDI: ffffffffffffff9c
RBP: 00007fc6431c1e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc643366128 R14: 00007fc643366090 R15: 00007ffd34495a58
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Tainted: G        W           6.17.0-rc1-syzkaller-00211-g90d970cade8e #0 PREEMPT_{RT,(full)} 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
 watchdog+0xf93/0xfe0 kernel/hung_task.c:491
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 28 Comm: rcuc/1 Tainted: G        W           6.17.0-rc1-syzkaller-00211-g90d970cade8e #0 PREEMPT_{RT,(full)} 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:unwind_get_return_address+0x3b/0x90 arch/x86/kernel/unwind_orc.c:369
Code: 00 00 fc ff df 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 4c 83 3b 00 74 3a 48 83 c3 48 49 89 df 49 c1 ef 03 43 80 3c 37 00 <74> 08 48 89 df e8 ab de aa 00 48 8b 3b e8 43 bc 19 00 85 c0 74 14
RSP: 0018:ffffc90000a2f628 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffc90000a2f690 RCX: 5704b2c5af9ba600
RDX: ffffffff8fb36001 RSI: ffffffff8b620b60 RDI: ffffc90000a2f648
RBP: ffffc90000a2f6d0 R08: ffffc90000a2f6a7 R09: 0000000000000000
R10: ffffc90000a2f698 R11: fffff52000145ed5 R12: ffff88801ca90000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000145ed2
FS:  0000000000000000(0000) GS:ffff8881269c5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9cd22f6000 CR3: 0000000034b38000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:243 [inline]
 __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2417 [inline]
 slab_free mm/slub.c:4680 [inline]
 kmem_cache_free+0x195/0x510 mm/slub.c:4782
 rcu_do_batch kernel/rcu/tree.c:2605 [inline]
 rcu_core kernel/rcu/tree.c:2861 [inline]
 rcu_cpu_kthread+0xbf3/0x1b50 kernel/rcu/tree.c:2949
 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/17 05:15 upstream 90d970cade8e 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in bch2_read_iter
* Struck through repros no longer work on HEAD.