INFO: task bch-copygc/loop:5227 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-02574-ga430d95c5efa #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:bch-copygc/loop state:D stack:20272 pid:5227 tgid:5227 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 __closure_sync+0x259/0x2f0 lib/closure.c:146 bch2_wait_on_allocator fs/bcachefs/alloc_foreground.h:238 [inline] __bch2_write+0x55a7/0x5d20 fs/bcachefs/io_write.c:1506 bch2_write+0x947/0x1670 fs/bcachefs/io_write.c:1633 closure_queue include/linux/closure.h:270 [inline] closure_call include/linux/closure.h:432 [inline] bch2_data_update_read_done+0x22e/0x330 fs/bcachefs/data_update.c:423 move_write fs/bcachefs/move.c:133 [inline] bch2_moving_ctxt_do_pending_writes+0x44c/0x8d0 fs/bcachefs/move.c:164 move_buckets_wait+0x2ba/0x1290 fs/bcachefs/movinggc.c:114 bch2_copygc_thread+0x83f/0xc20 fs/bcachefs/movinggc.c:386 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 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e738660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e738660 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e738660 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 2 locks held by getty/4971: #0: ffff8880301860a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-02574-ga430d95c5efa #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 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:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 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 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6032 Comm: syz-executor264 Not tainted 6.11.0-syzkaller-02574-ga430d95c5efa #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_switch+0xa4/0x120 kernel/kcov.c:350 Code: 8b 00 00 00 4c 8b 4c 24 20 65 4c 8b 1c 25 40 d4 03 00 31 d2 eb 08 48 ff c2 49 39 d2 74 71 4c 8b 74 d6 10 65 8b 05 d4 27 70 7e <25> 00 01 ff 00 74 11 3d 00 01 00 00 75 de 41 83 bb 1c 16 00 00 00 RSP: 0018:ffffc90004366e60 EFLAGS: 00000202 RAX: 0000000080000001 RBX: 0000000000000002 RCX: ffff888030d55a00 RDX: 0000000000000002 RSI: ffffffff8e5a4170 RDI: 0000000000000002 RBP: ffffffff908b0ad3 R08: 0000000000000005 R09: ffffffff81414746 R10: 0000000000000003 R11: ffff888030d55a00 R12: ffffffff908b0ad2 R13: dffffc0000000000 R14: 0000000000000004 R15: 1ffff9200086cdec FS: 0000555557f04480(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f37139ff000 CR3: 0000000032740000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0xff6/0x2a00 arch/x86/kernel/unwind_orc.c:581 arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __set_page_owner+0x92/0x800 mm/page_owner.c:320 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1500 prep_new_page mm/page_alloc.c:1508 [inline] get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3446 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4702 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2263 folio_alloc_mpol_noprof+0x36/0x50 mm/mempolicy.c:2281 shmem_alloc_folio mm/shmem.c:1722 [inline] shmem_alloc_and_add_folio+0x2cf/0x14f0 mm/shmem.c:1782 shmem_get_folio_gfp+0x8dc/0x2370 mm/shmem.c:2188 shmem_get_folio mm/shmem.c:2293 [inline] shmem_write_begin+0x170/0x450 mm/shmem.c:2898 generic_perform_write+0x37e/0x730 mm/filemap.c:4025 shmem_file_write_iter+0xf9/0x120 mm/shmem.c:3073 new_sync_write fs/read_write.c:590 [inline] vfs_write+0xa6d/0xc90 fs/read_write.c:683 ksys_write+0x1a0/0x2c0 fs/read_write.c:736 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: 0033:0x7f371aeb2890 Code: 40 00 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 80 3d f1 97 07 00 00 74 17 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 48 89 RSP: 002b:00007ffd8bd4e0c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007ffd8bd4e0e0 RCX: 00007f371aeb2890 RDX: 0000000001000000 RSI: 00007f3712a00000 RDI: 0000000000000003 RBP: 00007f3712a00000 R08: 0000000000005db3 R09: 0000000000005daf R10: 0000000000000032 R11: 0000000000000202 R12: 0000000000045f53 R13: 00007ffd8bd4e120 R14: 0000000000000003 R15: 0000000001000000 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.780 msecs