INFO: task syz.1.17:6464 blocked for more than 143 seconds. Not tainted 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.17 state:D stack:15688 pid:6464 tgid:6463 ppid:6349 task_flags:0x440140 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 __bch2_two_state_lock+0x1ea/0x370 fs/bcachefs/two_state_shared_lock.c:7 bch2_two_state_lock fs/bcachefs/two_state_shared_lock.h:55 [inline] bch2_readahead+0x94f/0x1100 fs/bcachefs/fs-io-buffered.c:296 read_pages+0x177/0x590 mm/readahead.c:160 page_cache_ra_order+0xa24/0xc70 mm/readahead.c:515 filemap_get_pages+0x43c/0x1eb0 mm/filemap.c:2591 filemap_splice_read+0x4fc/0xbc0 mm/filemap.c:2981 do_splice_read fs/splice.c:979 [inline] splice_direct_to_actor+0x4a6/0xcc0 fs/splice.c:1083 do_splice_direct_actor fs/splice.c:1201 [inline] do_splice_direct+0x181/0x270 fs/splice.c:1227 vfs_copy_file_range+0xabc/0x1310 fs/read_write.c:1625 __do_sys_copy_file_range fs/read_write.c:1675 [inline] __se_sys_copy_file_range+0x319/0x460 fs/read_write.c:1642 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: 0033:0x7fc24fd85d29 RSP: 002b:00007fc250c79038 EFLAGS: 00000246 ORIG_RAX: 0000000000000146 RAX: ffffffffffffffda RBX: 00007fc24ff75fa0 RCX: 00007fc24fd85d29 RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 00007fc24fe01b08 R08: 0000000000000080 R09: 0000000000000000 R10: 0000000020000280 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc24ff75fa0 R15: 00007fff831fbd08 INFO: task syz.1.17:6516 blocked for more than 144 seconds. Not tainted 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.17 state:D stack:25832 pid:6516 tgid:6463 ppid:6349 task_flags:0x400140 flags:0x00004004 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 io_schedule+0x81/0xe0 kernel/sched/core.c:7742 folio_wait_bit_common+0x6b0/0xb90 mm/filemap.c:1317 folio_lock include/linux/pagemap.h:1137 [inline] truncate_inode_pages_range+0xa77/0xda0 mm/truncate.c:429 bchfs_fallocate+0x2f4/0x680 fs/bcachefs/fs-io.c:757 bch2_fallocate_dispatch+0x345/0x4e0 fs/bcachefs/fs-io.c:810 vfs_fallocate+0x6a0/0x830 fs/open.c:338 ioctl_preallocate fs/ioctl.c:290 [inline] file_ioctl fs/ioctl.c:-1 [inline] do_vfs_ioctl+0x1b8f/0x1eb0 fs/ioctl.c:885 __do_sys_ioctl fs/ioctl.c:904 [inline] __se_sys_ioctl+0x82/0x170 fs/ioctl.c:892 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: 0033:0x7fc24fd85d29 RSP: 002b:00007fc250c58038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fc24ff76080 RCX: 00007fc24fd85d29 RDX: 0000000020000180 RSI: 0000000040305839 RDI: 0000000000000006 RBP: 00007fc24fe01b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc24ff76080 R15: 00007fff831fbd08 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8dde2e28 (wq_pool_mutex){+.+.}-{4:4}, at: pwq_release_workfn+0x3dc/0x870 kernel/workqueue.c:5091 4 locks held by kworker/u8:1/13: #0: ffff8880b88399d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605 #1: ffff8880b8823b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 #2: ffff8880b8823b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_change+0xe5/0x250 kernel/sched/psi.c:912 #3: ffffffff999c02f8 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xbb/0x420 lib/debugobjects.c:818 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 klogd/5178: #0: ffff8880b88399d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605 #1: ffff8880b8823b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 2 locks held by getty/5566: #0: ffff88814e5180a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036cb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz.1.17/6464: #0: ffff88805eb202e8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:922 [inline] ffff88805eb202e8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: page_cache_ra_order+0x445/0xc70 mm/readahead.c:491 2 locks held by syz.1.17/6516: #0: ffff88807c930420 (sb_writers#12){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff88807c930420 (sb_writers#12){.+.+}-{0:0}, at: vfs_fallocate+0x62a/0x830 fs/open.c:337 #1: ffff88805eb20148 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff88805eb20148 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: bch2_fallocate_dispatch+0x1ce/0x4e0 fs/bcachefs/fs-io.c:801 1 lock held by syz.4.362/9973: #0: ffffffff8dde2e28 (wq_pool_mutex){+.+.}-{4:4}, at: apply_wqattrs_lock kernel/workqueue.c:5179 [inline] #0: ffffffff8dde2e28 (wq_pool_mutex){+.+.}-{4:4}, at: __alloc_workqueue+0x9eb/0x1b70 kernel/workqueue.c:5734 1 lock held by syz.2.363/9982: #0: ffffffff8dde2e28 (wq_pool_mutex){+.+.}-{4:4}, at: destroy_workqueue+0x156/0xc70 kernel/workqueue.c:5878 1 lock held by syz.5.364/9984: #0: ffffffff8dde2e28 (wq_pool_mutex){+.+.}-{4:4}, at: apply_wqattrs_lock kernel/workqueue.c:5179 [inline] #0: ffffffff8dde2e28 (wq_pool_mutex){+.+.}-{4:4}, at: __alloc_workqueue+0x9eb/0x1b70 kernel/workqueue.c:5734 1 lock held by syz.3.365/9986: #0: ffffffff8dde2e28 (wq_pool_mutex){+.+.}-{4:4}, at: apply_wqattrs_lock kernel/workqueue.c:5179 [inline] #0: ffffffff8dde2e28 (wq_pool_mutex){+.+.}-{4:4}, at: __alloc_workqueue+0x9eb/0x1b70 kernel/workqueue.c:5734 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9986 Comm: syz.3.365 Not tainted 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:delay_tsc+0x5b/0xc0 arch/x86/lib/delay.c:79 Code: 90 49 89 d7 49 c1 e7 20 49 09 c7 4d 29 f7 49 39 df 73 53 bf 01 00 00 00 e8 d2 14 43 f6 65 8b 05 9b 57 24 07 85 c0 74 1c f3 90 01 00 00 00 e8 0b 13 43 f6 e8 e6 38 01 00 39 c5 75 0e 0f 01 f9 RSP: 0018:ffffc90003f7eeb0 EFLAGS: 00000002 RAX: 0000000000000002 RBX: 0000000000000899 RCX: 0000000000000000 RDX: 0000000000000090 RSI: ffffffff8bc0fa40 RDI: 00000000ffffffff RBP: 0000000000000000 R08: ffff888023e20237 R09: 1ffff110047c4046 R10: dffffc0000000000 R11: ffffffff8b4da840 R12: 1ffffffff3362f82 R13: 00000000ffffffff R14: 0000009037f883c0 R15: 0000000000000852 FS: 00007faa8f5fe6c0(0000) GS:ffff888126100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007faa90369160 CR3: 000000003f50c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: udelay include/asm-generic/delay.h:62 [inline] wait_for_lsr+0x160/0x2f0 drivers/tty/serial/8250/8250_port.c:2104 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3348 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3371 [inline] serial8250_console_write+0x134c/0x1ba0 drivers/tty/serial/8250/8250_port.c:3456 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x725/0xc40 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xc4/0x270 kernel/printk/printk.c:3325 vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450 bch2_print_maybe_redirect fs/bcachefs/super.c:110 [inline] __bch2_print+0x176/0x220 fs/bcachefs/super.c:129 bch2_fs_online+0xe1/0x4b0 fs/bcachefs/super.c:688 bch2_fs_alloc fs/bcachefs/super.c:960 [inline] bch2_fs_open+0x27a2/0x27e0 fs/bcachefs/super.c:2197 bch2_fs_get_tree+0x45d/0x1340 fs/bcachefs/fs.c:2489 vfs_get_tree+0x8f/0x2b0 fs/super.c:1759 do_new_mount+0x24a/0xa40 fs/namespace.c:3884 do_mount fs/namespace.c:4224 [inline] __do_sys_mount fs/namespace.c:4435 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4412 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: 0033:0x7faa903874ca Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007faa8f5fde68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007faa8f5fdef0 RCX: 00007faa903874ca RDX: 00000000200000c0 RSI: 0000000020000180 RDI: 00007faa8f5fdeb0 RBP: 00000000200000c0 R08: 00007faa8f5fdef0 R09: 0000000000000010 R10: 0000000000000010 R11: 0000000000000246 R12: 0000000020000180 R13: 00007faa8f5fdeb0 R14: 00000000000059d5 R15: 0000000020000480