INFO: task udevd:4899 blocked for more than 143 seconds. Not tainted 6.11.0-rc1-syzkaller-00033-g25f51b76f90f #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:26400 pid:4899 tgid:4899 ppid:2544 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xcda/0x2f80 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 device_lock include/linux/device.h:1009 [inline] uevent_show+0x188/0x3b0 drivers/base/core.c:2743 dev_attr_show+0x53/0xe0 drivers/base/core.c:2437 sysfs_kf_seq_show+0x23e/0x410 fs/sysfs/file.c:59 seq_read_iter+0x4fa/0x12c0 fs/seq_file.c:230 kernfs_fop_read_iter+0x41a/0x590 fs/kernfs/file.c:279 new_sync_read fs/read_write.c:395 [inline] vfs_read+0x869/0xbd0 fs/read_write.c:476 ksys_read+0x12f/0x260 fs/read_write.c:619 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1d92a71b6a RSP: 002b:00007ffc4bbca5e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000562ca427ae20 RCX: 00007f1d92a71b6a RDX: 0000000000001000 RSI: 0000562ca4285c80 RDI: 0000000000000008 RBP: 0000562ca427ae20 R08: 0000000000000008 R09: 0000000000000020 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007ffc4bbcaac8 R15: 000000000000000a Showing all locks held in the system: 1 lock held by rcu_preempt/16: #0: ffff8881f623d758 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:560 [inline] #0: ffff8881f623d758 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1415 [inline] #0: ffff8881f623d758 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1714 [inline] #0: ffff8881f623d758 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x28e/0x2f80 kernel/sched/core.c:6436 1 lock held by khungtaskd/30: #0: ffffffff88cb68a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff88cb68a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff88cb68a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6620 2 locks held by getty/2602: #0: ffff8881134f90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2211 4 locks held by udevd/4899: #0: ffff88811719b540 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xde/0x12c0 fs/seq_file.c:182 #1: ffff888120199888 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888111abfc38 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff8881318f3190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #3: ffff8881318f3190 (&dev->mutex){....}-{3:3}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2743 5 locks held by kworker/0:3/4917: 1 lock held by syz.4.390/6160: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc1-syzkaller-00033-g25f51b76f90f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 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+0xf4e/0x1280 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5153 Comm: udevd Not tainted 6.11.0-rc1-syzkaller-00033-g25f51b76f90f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:200 Code: be b0 01 00 00 e8 a0 ff ff ff 31 c0 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 65 48 8b 15 e4 5f b0 7e 65 8b 05 e5 5f b0 7e a9 00 01 RSP: 0018:ffffc9000f237418 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff8a422fcc RCX: ffffffff81155344 RDX: ffff88811c050000 RSI: ffffffff811552f0 RDI: 0000000000000006 RBP: ffffffff8a422fcc R08: 0000000000000006 R09: ffffffff81a82513 R10: ffffffff81a824f0 R11: 0000000000000000 R12: ffffffff81a82513 R13: ffffffff81a824f0 R14: dffffc0000000000 R15: ffffffff8a422fc8 FS: 00007f1d92946c80(0000) GS:ffff8881f6200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff6c6deff8 CR3: 000000011d76e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __orc_find+0x7a/0x130 arch/x86/kernel/unwind_orc.c:100 orc_find arch/x86/kernel/unwind_orc.c:227 [inline] unwind_next_frame+0x335/0x23a0 arch/x86/kernel/unwind_orc.c:494 arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object+0xf7/0x160 mm/kasan/common.c:240 __kasan_slab_free+0x14/0x30 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2252 [inline] slab_free mm/slub.c:4473 [inline] kmem_cache_free+0x110/0x380 mm/slub.c:4548 skb_kfree_head net/core/skbuff.c:1082 [inline] skb_kfree_head net/core/skbuff.c:1079 [inline] skb_free_head+0x18a/0x1d0 net/core/skbuff.c:1096 skb_release_data+0x772/0x920 net/core/skbuff.c:1123 skb_release_all net/core/skbuff.c:1188 [inline] __kfree_skb net/core/skbuff.c:1202 [inline] consume_skb net/core/skbuff.c:1426 [inline] consume_skb+0xd0/0x170 net/core/skbuff.c:1420 netlink_recvmsg+0x606/0xf30 net/netlink/af_netlink.c:1979 sock_recvmsg_nosec net/socket.c:1046 [inline] sock_recvmsg+0x1f6/0x250 net/socket.c:1068 ____sys_recvmsg+0x21f/0x6b0 net/socket.c:2816 ___sys_recvmsg+0x115/0x1a0 net/socket.c:2858 __sys_recvmsg+0x114/0x1e0 net/socket.c:2888 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1d92a7f91e Code: ff 89 ef 48 89 04 24 e8 4f 57 f9 ff 48 8b 04 24 48 83 c4 30 5d c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 21 b8 2f 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 70 48 8b 15 db c4 0c 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffc4bbd0ec8 EFLAGS: 00000246 ORIG_RAX: 000000000000002f RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1d92a7f91e RDX: 0000000000000000 RSI: 00007ffc4bbd0ef8 RDI: 000000000000000c RBP: 0000562ca428e6a0 R08: 0000000000000007 R09: 8917099a070c084f R10: 00000000ffffffff R11: 0000000000000246 R12: 0000562ca428e6a0 R13: 00007ffc4bbd0fb8 R14: 0000000000000000 R15: 0000562c9fb194df