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INFO: task hung in generic_file_write_iter (2)

Status: auto-obsoleted due to no activity on 2023/02/10 17:47
Subsystems: fs
[Documentation on labels]
First crash: 1220d, last: 1220d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in generic_file_write_iter (4) jfs 1 syz error 9 3d23h 7d08h 0/29 upstream: reported syz repro on 2026/02/25 03:09
android-49 INFO: task hung in generic_file_write_iter 1 2 2751d 2752d 0/3 auto-closed as invalid on 2019/02/22 14:09
upstream INFO: task hung in generic_file_write_iter mm fs 1 7 2647d 2786d 11/29 fixed on 2019/03/06 07:43
upstream INFO: task hung in generic_file_write_iter (3) exfat 1 C error 4 184d 223d 29/29 fixed on 2025/09/04 16:57

Sample crash report:
INFO: task syz-executor.3:25632 blocked for more than 143 seconds.
      Not tainted 6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:23864 pid:25632 ppid:17920  flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5191 [inline]
 __schedule+0x8c9/0xd70 kernel/sched/core.c:6503
 schedule+0xcb/0x190 kernel/sched/core.c:6579
 rwsem_down_write_slowpath+0xfc1/0x1480 kernel/locking/rwsem.c:1190
 __down_write_common kernel/locking/rwsem.c:1305 [inline]
 __down_write kernel/locking/rwsem.c:1314 [inline]
 down_write+0x231/0x270 kernel/locking/rwsem.c:1563
 inode_lock include/linux/fs.h:756 [inline]
 generic_file_write_iter+0x7f/0x310 mm/filemap.c:3910
 do_iter_write+0x6c2/0xc20 fs/read_write.c:861
 iter_file_splice_write+0x7fc/0xfc0 fs/splice.c:686
 do_splice_from fs/splice.c:764 [inline]
 direct_splice_actor+0xe6/0x1c0 fs/splice.c:931
 splice_direct_to_actor+0x4e4/0xc00 fs/splice.c:886
 do_splice_direct+0x279/0x3d0 fs/splice.c:974
 do_sendfile+0x5fb/0xf80 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64+0x14f/0x1b0 fs/read_write.c:1309
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fec5c28b5a9
RSP: 002b:00007fec5cfa3168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fec5c3abf80 RCX: 00007fec5c28b5a9
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000007
RBP: 00007fec5c2e67b0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000f03b0000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffce45e435f R14: 00007fec5cfa3300 R15: 0000000000022000
 </TASK>
INFO: task syz-executor.3:25634 blocked for more than 143 seconds.
      Not tainted 6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:24056 pid:25634 ppid:17920  flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5191 [inline]
 __schedule+0x8c9/0xd70 kernel/sched/core.c:6503
 schedule+0xcb/0x190 kernel/sched/core.c:6579
 io_schedule+0x83/0x100 kernel/sched/core.c:8723
 folio_wait_bit_common+0x83a/0x12a0 mm/filemap.c:1296
 folio_wait_writeback+0xf8/0x200 mm/page-writeback.c:3036
 __filemap_fdatawait_range+0x20c/0x780 mm/filemap.c:524
 filemap_write_and_wait_range+0x1ff/0x2b0 mm/filemap.c:683
 __generic_file_write_iter+0x2cc/0x400 mm/filemap.c:3867
 generic_file_write_iter+0xab/0x310 mm/filemap.c:3913
 do_iter_write+0x6c2/0xc20 fs/read_write.c:861
 iter_file_splice_write+0x7fc/0xfc0 fs/splice.c:686
 do_splice_from fs/splice.c:764 [inline]
 direct_splice_actor+0xe6/0x1c0 fs/splice.c:931
 splice_direct_to_actor+0x4e4/0xc00 fs/splice.c:886
 do_splice_direct+0x279/0x3d0 fs/splice.c:974
 do_sendfile+0x5fb/0xf80 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64+0x14f/0x1b0 fs/read_write.c:1309
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fec5c28b5a9
RSP: 002b:00007fec5cf82168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fec5c3ac050 RCX: 00007fec5c28b5a9
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000007
RBP: 00007fec5c2e67b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0008000000000004 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffce45e435f R14: 00007fec5cf82300 R15: 0000000000022000
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46f/0x4f0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1ba/0x420 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xcf5/0xd40 kernel/hung_task.c:377
 kthread+0x266/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 28367 Comm: kworker/u4:59 Not tainted 6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
Workqueue: phy24 ieee80211_iface_work
RIP: 0010:lock_acquire+0x93/0x3c0 kernel/locking/lockdep.c:5636
Code: f2 4b 89 44 25 00 43 c7 44 25 09 f2 f2 f2 00 43 c7 44 25 11 f3 f3 f3 f3 66 43 c7 44 25 15 f3 f3 43 c6 44 25 17 f3 89 54 24 0c <89> 4c 24 08 4c 89 4c 24 18 ff 75 10 e8 1c 03 00 00 48 83 c4 08 48
RSP: 0018:ffffc90007b2f740 EFLAGS: 00000a02
RAX: f2f2f200f1f1f1f1 RBX: ffff8880a2d40168 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880a2d40168
RBP: ffffc90007b2f878 R08: 0000000000000001 R09: 0000000000000000
R10: fffff52000f65f0a R11: 1ffff92000f65f04 R12: dffffc0000000000
R13: 1ffff92000f65eec R14: 0000000000000001 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c014b06680 CR3: 0000000027be9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
 _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
 spin_lock_bh include/linux/spinlock.h:355 [inline]
 cfg80211_put_bss+0x39/0x230 net/wireless/scan.c:2593
 ieee80211_rx_bss_info net/mac80211/ibss.c:1192 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1609 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x1ac1/0x2c00 net/mac80211/ibss.c:1638
 ieee80211_iface_process_skb net/mac80211/iface.c:1630 [inline]
 ieee80211_iface_work+0x773/0xcf0 net/mac80211/iface.c:1684
 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289
 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
 kthread+0x266/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/10/30 21:30 upstream b229b6ca5abb 2a71366b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in generic_file_write_iter
* Struck through repros no longer work on HEAD.