INFO: task syz.4.3027:16297 blocked for more than 143 seconds. Not tainted 6.16.0-rc2-syzkaller-00318-g739a6c93cc75 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.3027 state:D stack:28328 pid:16297 tgid:16295 ppid:16012 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747 blk_trace_startstop+0xa3/0x640 kernel/trace/blktrace.c:700 blk_trace_ioctl+0x19b/0x430 kernel/trace/blktrace.c:742 blkdev_common_ioctl+0xdce/0x2450 block/ioctl.c:629 blkdev_ioctl+0x4ef/0x6d0 block/ioctl.c:698 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 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: 0033:0x7f6ef178e929 RSP: 002b:00007f6ef2512038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f6ef19b6080 RCX: 00007f6ef178e929 RDX: 0000000000000000 RSI: 0000000000001275 RDI: 0000000000000045 RBP: 00007f6ef1810b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f6ef19b6080 R15: 00007f6ef1adfa28 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 3 locks held by udevd/5200: 2 locks held by getty/5591: #0: ffff888030e560a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by syz.0.3025/16291: 1 lock held by syz.4.3027/16297: #0: ffff888142b53040 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_startstop+0xa3/0x640 kernel/trace/blktrace.c:700 1 lock held by syz.1.3447/17838: 2 locks held by syz.1.3447/17849: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc2-syzkaller-00318-g739a6c93cc75 #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:307 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 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: 16291 Comm: syz.0.3025 Not tainted 6.16.0-rc2-syzkaller-00318-g739a6c93cc75 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:__reset_page_owner+0x28/0x1f0 mm/page_owner.c:295 Code: 90 90 66 0f 1f 00 55 41 57 41 56 41 55 41 54 53 89 f5 49 89 fe e8 d8 32 93 ff e8 93 69 6d ff 49 89 c7 4c 89 f7 e8 78 bf 01 00 <48> 85 c0 0f 84 52 01 00 00 48 8b 0d 38 a0 fa 0b 48 8d 1c 08 48 83 RSP: 0018:ffffc9000422f930 EFLAGS: 00000246 RAX: ffff888140e710f0 RBX: 0000000000000000 RCX: 0000000000080000 RDX: ffffc9000e182000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff822ee952 R10: dffffc0000000000 R11: fffff94000abe81f R12: ffffea00055f40c0 R13: ffffea00055f40c8 R14: ffffea00055f40c0 R15: 000000d6cdf48a13 FS: 00007f24b45f66c0(0000) GS:ffff888125c51000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000005486c000 CR4: 00000000003526f0 Call Trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706 relay_destroy_buf+0x10e/0x3a0 kernel/relay.c:201 relay_remove_buf kernel/relay.c:221 [inline] kref_put include/linux/kref.h:65 [inline] relay_close_buf kernel/relay.c:429 [inline] relay_open+0x734/0x920 kernel/relay.c:525 do_blk_trace_setup+0x591/0x9d0 kernel/trace/blktrace.c:590 blk_trace_setup+0x116/0x1f0 kernel/trace/blktrace.c:632 blk_trace_ioctl+0x181/0x430 kernel/trace/blktrace.c:730 blkdev_ioctl+0x416/0x6d0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 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: 0033:0x7f24b678e929 Code: Unable to access opcode bytes at 0x7f24b678e8ff. RSP: 002b:00007f24b45f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f24b69b6080 RCX: 00007f24b678e929 RDX: 0000200000001240 RSI: 00000000c0481273 RDI: 0000000000000003 RBP: 00007f24b6810b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f24b69b6080 R15: 00007f24b6adfa28