INFO: task syz.7.268:8643 blocked for more than 143 seconds. Not tainted 6.15.0-rc5-syzkaller-00300-g3ce9925823c7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.268 state:D stack:19816 pid:8643 tgid:8641 ppid:7580 task_flags:0x400140 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 __closure_sync+0x163/0x220 lib/closure.c:146 closure_sync include/linux/closure.h:195 [inline] bch2_direct_IO_read fs/bcachefs/fs-io-direct.c:179 [inline] bch2_read_iter+0x1035/0x1440 fs/bcachefs/fs-io-direct.c:214 new_sync_read fs/read_write.c:489 [inline] vfs_read+0x4cd/0x980 fs/read_write.c:570 ksys_read+0x145/0x250 fs/read_write.c:713 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe8c158e969 RSP: 002b:00007fe8c24c1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007fe8c17b5fa0 RCX: 00007fe8c158e969 RDX: 0000000000001000 RSI: 0000200000000400 RDI: 0000000000000005 RBP: 00007fe8c1610ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe8c17b5fa0 R15: 00007fffada5cfc8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 2 locks held by udevd/5192: 2 locks held by getty/5582: #0: ffff888033e0a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036c32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by udevd/5823: 1 lock held by syz.7.268/8643: #0: ffff88803227e7f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1213 2 locks held by syz-executor/9425: 2 locks held by syz.0.526/11180: 1 lock held by syz.8.523/11184: 3 locks held by dhcpcd-run-hook/11206: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc5-syzkaller-00300-g3ce9925823c7 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5823 Comm: udevd Not tainted 6.15.0-rc5-syzkaller-00300-g3ce9925823c7 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:resched_offsets_ok kernel/sched/core.c:8767 [inline] RIP: 0010:__might_resched+0x155/0x610 kernel/sched/core.c:8782 Code: 44 8b 3d 7e 8b df 10 41 81 e7 ff ff ff 7f 65 48 8b 14 25 08 00 72 92 4c 8d b2 44 04 00 00 4d 89 f4 49 c1 ec 03 43 0f b6 04 2c <84> c0 0f 85 49 03 00 00 41 8b 06 c1 e0 08 44 01 f8 3b 44 24 2c 75 RSP: 0018:ffffc90004317580 EFLAGS: 00000a07 RAX: 0000000000000000 RBX: 1ffff92000862eb8 RCX: 7075b522161d7600 RDX: ffff88805acc0000 RSI: ffffffff8d921532 RDI: ffffffff8bc0ffa0 RBP: ffffc90004317698 R08: ffff88805acc0000 R09: 0000000000000004 R10: 0000000000000003 R11: 0000000000000000 R12: 1ffff1100b598088 R13: dffffc0000000000 R14: ffff88805acc0444 R15: 0000000000000000 FS: 00007fce7f619880(0000) GS:ffff888126200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fce7f615000 CR3: 0000000076d9e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: down_read+0x22/0x2e0 kernel/locking/rwsem.c:1523 anon_vma_lock_read include/linux/rmap.h:137 [inline] validate_mm+0x1d4/0x4b0 mm/vma.c:623 __split_vma+0x867/0x9b0 mm/vma.c:524 vms_gather_munmap_vmas+0x2de/0x12b0 mm/vma.c:1315 do_vmi_align_munmap+0x25d/0x420 mm/vma.c:1483 do_vmi_munmap+0x253/0x2e0 mm/vma.c:1540 __vm_munmap+0x23b/0x3d0 mm/vma.c:3013 __do_sys_munmap mm/mmap.c:1084 [inline] __se_sys_munmap mm/mmap.c:1081 [inline] __x64_sys_munmap+0x60/0x70 mm/mmap.c:1081 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fce7ef1e097 Code: 73 01 c3 48 8b 0d 61 2d 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 31 2d 0d 00 f7 d8 64 89 01 48 RSP: 002b:00007fffb3209788 EFLAGS: 00000246 ORIG_RAX: 000000000000000b RAX: ffffffffffffffda RBX: 0000555e8075e350 RCX: 00007fce7ef1e097 RDX: 0000555e8075e398 RSI: 0000000000000200 RDI: 00007fce7f60b000 RBP: 000000000000000c R08: 0000555e80769480 R09: 0000000000000003 R10: 0000000000000000 R11: 0000000000000246 R12: 0000555e8076dc80 R13: 00007fce7f74039c R14: 0000000000001800 R15: 0000000000000009