INFO: task syz-executor:8207 blocked for more than 143 seconds.
      Tainted: G        W           6.17.0-rc2-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21960 pid:8207  tgid:8207  ppid:1      task_flags:0x400140 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
 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:100 [inline]
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common kernel/sched/completion.c:132 [inline]
 wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153
 kthread_stop+0x194/0x5c0 kernel/kthread.c:790
 bch2_copygc_stop+0x4b/0x120 fs/bcachefs/movinggc.c:438
 __bch2_fs_read_only+0x47/0x5b0 fs/bcachefs/super.c:280
 bch2_fs_read_only+0x42a/0xb00 fs/bcachefs/super.c:366
 __bch2_fs_stop+0x100/0x900 fs/bcachefs/super.c:677
 generic_shutdown_super+0x132/0x2c0 fs/super.c:643
 bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2618
 deactivate_locked_super+0xbc/0x130 fs/super.c:474
 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1378
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f03d828ff17
RSP: 002b:00007ffce46a95e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f03d8311c05 RCX: 00007f03d828ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffce46a96a0
RBP: 00007ffce46a96a0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffce46aa730
R13: 00007f03d8311c05 R14: 00000000000613d2 R15: 00007ffce46aa770
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Tainted: G        W           6.17.0-rc2-syzkaller #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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 13449 Comm: syz.0.758 Tainted: G        W           6.17.0-rc2-syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x19/0xa0 kernel/kcov.c:314
Code: 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 b0 f5 91 65 44 8b 05 27 50 37 10 <41> 81 e0 00 00 ff 00 ba 00 01 00 00 23 91 0c 0b 00 00 41 89 d1 45
RSP: 0018:ffffc900064d7700 EFLAGS: 00000246
RAX: ffffffff821e193b RBX: 0000000000000000 RCX: ffff88802f003b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000020
RBP: 0000000000000000 R08: 0000000080000000 R09: 0000000000000000
R10: ffffc900064d77e0 R11: fffff52000c9af01 R12: 1ffff92000c9aef7
R13: 0000000000140cca R14: 0000000000000000 R15: 1ffff92000c9ae01
FS:  00007f6b1eb766c0(0000) GS:ffff8881268c5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001240 CR3: 0000000070cb6000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 should_fail_alloc_page+0xbb/0x100 mm/fail_page_alloc.c:44
 prepare_alloc_pages+0x213/0x670 mm/page_alloc.c:4923
 __alloc_frozen_pages_noprof+0x123/0x370 mm/page_alloc.c:5137
 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2416
 folio_alloc_mpol_noprof+0x39/0xe0 mm/mempolicy.c:2435
 shmem_alloc_folio mm/shmem.c:1908 [inline]
 shmem_alloc_and_add_folio mm/shmem.c:1947 [inline]
 shmem_get_folio_gfp+0x633/0x1a70 mm/shmem.c:2597
 shmem_get_folio mm/shmem.c:2703 [inline]
 shmem_write_begin+0xef/0x2a0 mm/shmem.c:3353
 generic_perform_write+0x29a/0x8c0 mm/filemap.c:4175
 shmem_file_write_iter+0xfb/0x120 mm/shmem.c:3528
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x5d2/0xb40 fs/read_write.c:686
 ksys_write+0x14b/0x260 fs/read_write.c:738
 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: 0033:0x7f6b2090d69f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007f6b1eb75df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f6b2090d69f
RDX: 0000000001000000 RSI: 00007f6b16735000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000005594
R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000003
R13: 00007f6b1eb75ef0 R14: 00007f6b1eb75eb0 R15: 00007f6b16735000
 </TASK>