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INFO: task hung in bch2_mark_pagecache_reserved (2)

Status: auto-obsoleted due to no activity on 2025/04/03 14:49
Subsystems: bcachefs
[Documentation on labels]
First crash: 236d, last: 236d
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in bch2_mark_pagecache_reserved bcachefs 1 4 381d 458d 0/29 auto-obsoleted due to no activity on 2024/11/09 10:13
upstream INFO: task hung in bch2_mark_pagecache_reserved (3) bcachefs 1 C error 2 9d18h 5d23h 0/29 upstream: reported C repro on 2025/08/22 04:15

Sample crash report:
INFO: task syz.9.1586:19736 blocked for more than 143 seconds.
      Not tainted 6.13.0-rc5-syzkaller-00012-g0bc21e701a6f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.1586      state:D stack:12112 pid:19736 tgid:19735 ppid:16453  flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6848
 io_schedule+0x8d/0x110 kernel/sched/core.c:7681
 folio_wait_bit_common+0x839/0xee0 mm/filemap.c:1308
 folio_lock include/linux/pagemap.h:1151 [inline]
 bch2_mark_pagecache_reserved+0x388/0xc60 fs/bcachefs/fs-io-pagecache.c:314
 __bchfs_fallocate+0x180e/0x2770 fs/bcachefs/fs-io.c:677
 bchfs_fallocate+0x31b/0x730 fs/bcachefs/fs-io.c:733
 bch2_fallocate_dispatch+0x3ac/0x540 fs/bcachefs/fs-io.c:780
 vfs_fallocate+0x569/0x6e0 fs/open.c:327
 do_vfs_ioctl+0x258c/0x2e40 fs/ioctl.c:885
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl+0x80/0x170 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff308185d29
RSP: 002b:00007ff30902e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ff308375fa0 RCX: 00007ff308185d29
RDX: 0000000020000180 RSI: 0000000040305839 RDI: 0000000000000007
RBP: 00007ff308201b08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff308375fa0 R15: 00007ffe2fc27878
 </TASK>
INFO: task syz.9.1586:19783 blocked for more than 144 seconds.
      Not tainted 6.13.0-rc5-syzkaller-00012-g0bc21e701a6f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.1586      state:D stack:15312 pid:19783 tgid:19735 ppid:16453  flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6848
 __bch2_two_state_lock+0x229/0x2c0 fs/bcachefs/two_state_shared_lock.c:7
 bch2_two_state_lock fs/bcachefs/two_state_shared_lock.h:55 [inline]
 bch2_readahead+0x9a2/0x11e0 fs/bcachefs/fs-io-buffered.c:258
 read_pages+0x176/0x750 mm/readahead.c:160
 page_cache_ra_order+0x7e3/0xb60 mm/readahead.c:512
 page_cache_sync_readahead include/linux/pagemap.h:1397 [inline]
 filemap_get_pages+0x605/0x2080 mm/filemap.c:2546
 filemap_splice_read+0x68e/0xef0 mm/filemap.c:2922
 do_splice_read fs/splice.c:985 [inline]
 splice_direct_to_actor+0x4af/0xc80 fs/splice.c:1089
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0x289/0x3e0 fs/splice.c:1233
 do_sendfile+0x564/0x8a0 fs/read_write.c:1363
 __do_sys_sendfile64 fs/read_write.c:1424 [inline]
 __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1410
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff308185d29
RSP: 002b:00007ff308fec038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007ff308376160 RCX: 00007ff308185d29
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000005
RBP: 00007ff308201b08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000100001 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff308376160 R15: 00007ffe2fc27878
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc5-syzkaller-00012-g0bc21e701a6f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline]
 watchdog+0xff6/0x1040 kernel/hung_task.c:397
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5809 Comm: udevd Not tainted 6.13.0-rc5-syzkaller-00012-g0bc21e701a6f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__might_resched+0x2ef/0x780 kernel/sched/core.c:8760
Code: e7 cd f1 0c 48 8b 05 80 d0 a8 11 48 29 c1 48 83 c1 9c 79 57 48 85 c0 74 52 48 c7 44 24 40 0e 36 e0 45 4a c7 04 3a 00 00 00 00 <42> c7 44 3a 09 00 00 00 00 66 42 c7 44 3a 0d 00 00 42 c6 44 3a 0f
RSP: 0018:ffffc90003fbf700 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 1ffff920007f7ef4 RCX: dffffc0000000000
RDX: dffffc0000000000 RSI: ffff88807f4e3c00 RDI: ffffc90003fbf7a0
RBP: ffffc90003fbf808 R08: ffffffff901853f7 R09: 1ffffffff2030a7e
R10: dffffc0000000000 R11: fffffbfff2030a7f R12: 0000000000000000
R13: ffff88807f4e4044 R14: 0000000000000141 R15: 1ffff920007f7ee8
FS:  00007efee3ca3c80(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055f79dbdf620 CR3: 0000000035804000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 might_alloc include/linux/sched/mm.h:321 [inline]
 slab_pre_alloc_hook mm/slub.c:4070 [inline]
 slab_alloc_node mm/slub.c:4148 [inline]
 kmem_cache_alloc_noprof+0x61/0x380 mm/slub.c:4175
 vma_lock_alloc kernel/fork.c:446 [inline]
 vm_area_dup+0x61/0x290 kernel/fork.c:499
 dup_mmap kernel/fork.c:694 [inline]
 dup_mm kernel/fork.c:1691 [inline]
 copy_mm+0xb95/0x1fd0 kernel/fork.c:1743
 copy_process+0x1845/0x3d50 kernel/fork.c:2394
 kernel_clone+0x223/0x870 kernel/fork.c:2806
 __do_sys_clone kernel/fork.c:2949 [inline]
 __se_sys_clone kernel/fork.c:2933 [inline]
 __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2933
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efee38fca12
Code: 41 5d 41 5e 41 5f c3 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 10 48 8b 15 e7 43 0f 00 f7 d8 64 89 02 48 83
RSP: 002b:00007fff1b0a7398 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 000055f79dbef801 RCX: 00007efee38fca12
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 000055f79dbef890 R08: 0000000000000000 R09: 000055f769ce0160
R10: 00007efee3ca3f50 R11: 0000000000000246 R12: 00007fff1b0a7998
R13: 0000000000000000 R14: 0000000000000000 R15: 00007fff1b0a9218
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/03 14:41 upstream 0bc21e701a6f d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in bch2_mark_pagecache_reserved
* Struck through repros no longer work on HEAD.