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INFO: task hung in erofs_bread

Status: upstream: reported C repro on 2024/12/09 17:51
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+5a27cfbb1410f017c309@syzkaller.appspotmail.com
First crash: 328d, last: 4d23h
Fix bisection: the issue occurs on the latest tested release (bisect log)
Crash: INFO: rcu detected stall in corrupted (log)
Repro: C syz .config
  
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/06/16 linux-6.1.y (ToT) 58485ff1a74f C [report] INFO: task hung in erofs_bread
2025/06/16 upstream (ToT) e04c78d86a96 C Didn't crash
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in erofs_bread erofs 1 C 4 49d 48d 29/29 fixed on 2025/10/29 21:02
▶ ▼ Fix bisection attempts (2)
Created Duration User Patch Repo Result
2025/08/17 22:37 2h13m fix candidate upstream OK (0) job log
2025/07/17 23:17 2h34m bisect fix linux-6.1.y OK (0) job log log

Sample crash report:
INFO: task syz-executor402:4292 blocked for more than 143 seconds.
      Not tainted 6.1.141-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor402 state:D
 stack:25832 pid:4292  ppid:4277   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8797
 folio_wait_bit_common+0x6e1/0xf60 mm/filemap.c:1324
 folio_put_wait_locked mm/filemap.c:1493 [inline]
 do_read_cache_folio+0x1a9/0x760 mm/filemap.c:3609
 erofs_bread+0x18e/0x670 fs/erofs/data.c:50
 erofs_find_target_block fs/erofs/namei.c:102 [inline]
 erofs_namei+0x28f/0xf00 fs/erofs/namei.c:175
 erofs_lookup+0x14b/0x390 fs/erofs/namei.c:204
 __lookup_slow+0x27d/0x3a0 fs/namei.c:1690
 lookup_slow+0x53/0x70 fs/namei.c:1707
 walk_component+0x2be/0x3f0 fs/namei.c:1998
 lookup_last fs/namei.c:2455 [inline]
 path_lookupat+0x169/0x440 fs/namei.c:2479
 filename_lookup+0x1f0/0x500 fs/namei.c:2508
 kern_path+0x31/0x50 fs/namei.c:2606
 unix_find_bsd net/unix/af_unix.c:1039 [inline]
 unix_find_other+0xf5/0x7f0 net/unix/af_unix.c:1100
 unix_dgram_sendmsg+0x8e3/0x16c0 net/unix/af_unix.c:1962
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x59b/0x970 net/socket.c:2519
 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573
 __sys_sendmmsg+0x272/0x490 net/socket.c:2659
 __do_sys_sendmmsg net/socket.c:2688 [inline]
 __se_sys_sendmmsg net/socket.c:2685 [inline]
 __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2685
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f54678b0d49
RSP: 002b:00007f546784c218 EFLAGS: 00000246
 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f54679386d8 RCX: 00007f54678b0d49
RDX: 0000000000000002 RSI: 00002000000254c0 RDI: 0000000000000005
RBP: 00007f54679386d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000001580
R13: 0000200000025500 R14: 00002000000254c0 R15: 0000200000000204
 </TASK>
INFO: task syz-executor402:4294 blocked for more than 147 seconds.
      Not tainted 6.1.141-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor402 state:D
 stack:26208 pid:4294  ppid:4276   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8797
 folio_wait_bit_common+0x6e1/0xf60 mm/filemap.c:1324
 folio_put_wait_locked mm/filemap.c:1493 [inline]
 do_read_cache_folio+0x1a9/0x760 mm/filemap.c:3609
 erofs_bread+0x18e/0x670 fs/erofs/data.c:50
 erofs_find_target_block fs/erofs/namei.c:102 [inline]
 erofs_namei+0x28f/0xf00 fs/erofs/namei.c:175
 erofs_lookup+0x14b/0x390 fs/erofs/namei.c:204
 __lookup_slow+0x27d/0x3a0 fs/namei.c:1690
 lookup_slow+0x53/0x70 fs/namei.c:1707
 walk_component+0x2be/0x3f0 fs/namei.c:1998
 lookup_last fs/namei.c:2455 [inline]
 path_lookupat+0x169/0x440 fs/namei.c:2479
 filename_lookup+0x1f0/0x500 fs/namei.c:2508
 kern_path+0x31/0x50 fs/namei.c:2606
 unix_find_bsd net/unix/af_unix.c:1039 [inline]
 unix_find_other+0xf5/0x7f0 net/unix/af_unix.c:1100
 unix_dgram_sendmsg+0x8e3/0x16c0 net/unix/af_unix.c:1962
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x59b/0x970 net/socket.c:2519
 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573
 __sys_sendmmsg+0x272/0x490 net/socket.c:2659
 __do_sys_sendmmsg net/socket.c:2688 [inline]
 __se_sys_sendmmsg net/socket.c:2685 [inline]
 __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2685
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f54678b0d49
RSP: 002b:00007f546784c218 EFLAGS: 00000246
 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f54679386d8 RCX: 00007f54678b0d49
RDX: 0000000000000002 RSI: 00002000000254c0 RDI: 0000000000000005
RBP: 00007f54679386d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000001580
R13: 0000200000025500 R14: 00002000000254c0 R15: 0000200000000204
 </TASK>
INFO: task syz-executor402:4295 blocked for more than 150 seconds.
      Not tainted 6.1.141-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor402 state:D
 stack:26208 pid:4295  ppid:4278   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8797
 folio_wait_bit_common+0x6e1/0xf60 mm/filemap.c:1324
 folio_put_wait_locked mm/filemap.c:1493 [inline]
 do_read_cache_folio+0x1a9/0x760 mm/filemap.c:3609
 erofs_bread+0x18e/0x670 fs/erofs/data.c:50
 erofs_find_target_block fs/erofs/namei.c:102 [inline]
 erofs_namei+0x28f/0xf00 fs/erofs/namei.c:175
 erofs_lookup+0x14b/0x390 fs/erofs/namei.c:204
 __lookup_slow+0x27d/0x3a0 fs/namei.c:1690
 lookup_slow+0x53/0x70 fs/namei.c:1707
 walk_component+0x2be/0x3f0 fs/namei.c:1998
 lookup_last fs/namei.c:2455 [inline]
 path_lookupat+0x169/0x440 fs/namei.c:2479
 filename_lookup+0x1f0/0x500 fs/namei.c:2508
 kern_path+0x31/0x50 fs/namei.c:2606
 unix_find_bsd net/unix/af_unix.c:1039 [inline]
 unix_find_other+0xf5/0x7f0 net/unix/af_unix.c:1100
 unix_dgram_sendmsg+0x8e3/0x16c0 net/unix/af_unix.c:1962
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x59b/0x970 net/socket.c:2519
 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573
 __sys_sendmmsg+0x272/0x490 net/socket.c:2659
 __do_sys_sendmmsg net/socket.c:2688 [inline]
 __se_sys_sendmmsg net/socket.c:2685 [inline]
 __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2685
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f54678b0d49
RSP: 002b:00007f546784c218 EFLAGS: 00000246
 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f54679386d8 RCX: 00007f54678b0d49
RDX: 0000000000000002 RSI: 00002000000254c0 RDI: 0000000000000005
RBP: 00007f54679386d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000001580
R13: 0000200000025500 R14: 00002000000254c0 R15: 0000200000000204
 </TASK>
INFO: task syz-executor402:4296 blocked for more than 153 seconds.
      Not tainted 6.1.141-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor402 state:D

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/13 17:59 linux-6.1.y 58485ff1a74f 98683f8f .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan INFO: task hung in erofs_bread
2025/10/29 14:39 linux-6.1.y 8e6e2188d949 fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in erofs_bread
2025/08/13 13:07 linux-6.1.y 3594f306da12 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in erofs_bread
2025/06/13 16:28 linux-6.1.y 58485ff1a74f 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in erofs_bread
2025/03/18 01:53 linux-6.1.y 344a09659766 ce3352cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in erofs_bread
2024/12/09 17:51 linux-6.1.y e4d90d63d385 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in erofs_bread
* Struck through repros no longer work on HEAD.