INFO: task syz.6.893:3042 blocked for more than 123 seconds. Not tainted 6.12.30-syzkaller-g2e58e85c038f #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.893 state:D stack:0 pid:3042 tgid:3041 ppid:2087 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x132b/0x1e00 kernel/sched/core.c:7789 __schedule_loop kernel/sched/core.c:7870 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7885 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7942 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285 device_lock include/linux/device.h:1025 [inline] usbdev_open+0x171/0x840 drivers/usb/core/devio.c:1051 chrdev_open+0x4db/0x5f0 fs/char_dev.c:414 do_dentry_open+0x978/0x1510 fs/open.c:960 vfs_open+0x86/0x230 fs/open.c:1090 do_open fs/namei.c:3774 [inline] path_openat+0x2b6c/0x34b0 fs/namei.c:3933 do_filp_open+0x1c6/0x3e0 fs/namei.c:3960 do_sys_openat2+0x12c/0x1c0 fs/open.c:1438 do_sys_open fs/open.c:1453 [inline] __do_sys_openat fs/open.c:1469 [inline] __se_sys_openat fs/open.c:1464 [inline] __x64_sys_openat+0x13a/0x170 fs/open.c:1464 x64_sys_call+0xe69/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:258 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f569538d310 RSP: 002b:00007f56961e1b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000402 RCX: 00007f569538d310 RDX: 0000000000000402 RSI: 00007f56961e1c10 RDI: 00000000ffffff9c RBP: 00007f56961e1c10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 0000000000000001 R14: 00007f56955b5fa0 R15: 00007ffe44ee79c8 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted 6.12.30-syzkaller-g2e58e85c038f #0 c5e7ad78b71ddb211d6a9cda70735ca8545dcbc5 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline] watchdog+0xd8f/0xed0 kernel/hung_task.c:423 kthread+0x2c7/0x370 kernel/kthread.c:389 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153 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: 33 Comm: rcuop/1 Not tainted 6.12.30-syzkaller-g2e58e85c038f #0 c5e7ad78b71ddb211d6a9cda70735ca8545dcbc5 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:update_stack_state+0x12e/0x4b0 arch/x86/kernel/unwind_frame.c:-1 Code: 8d 73 20 48 89 b5 60 ff ff ff 4c 89 f6 48 c1 ee 03 48 89 b5 40 ff ff ff 48 89 8d 70 ff ff ff 48 c1 e9 03 48 89 8d 48 ff ff ff <48> 89 95 58 ff ff ff 48 c1 ea 03 48 89 95 68 ff ff ff 48 89 45 c0 RSP: 0018:ffffc900000070f8 EFLAGS: 00000a06 RAX: ffffc90000007270 RBX: ffffc90000007248 RCX: 1ffff92000000e4b RDX: ffffc90000007260 RSI: 1ffff92000000e4a RDI: ffffc900000072a0 RBP: ffffc900000071b8 R08: ffffc90000007310 R09: ffffc90000007308 R10: 0000000000000011 R11: ffffffff81740950 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffc90000007250 R15: ffffc90000227ed0 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5e16ee7d60 CR3: 000000010cbf8000 CR4: 00000000003526b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0x3c2/0x750 arch/x86/kernel/unwind_frame.c:315 arch_stack_walk+0x139/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9d/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:565 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x73/0x90 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4164 [inline] slab_alloc_node mm/slub.c:4213 [inline] kmem_cache_alloc_noprof+0x131/0x3a0 mm/slub.c:4222 skb_clone+0x229/0x460 net/core/skbuff.c:2094 deliver_clone net/bridge/br_forward.c:125 [inline] maybe_deliver net/bridge/br_forward.c:190 [inline] br_flood+0x4ed/0x730 net/bridge/br_forward.c:236 br_handle_frame_finish+0x12bb/0x1720 net/bridge/br_input.c:215 nf_hook_bridge_pre net/bridge/br_input.c:301 [inline] br_handle_frame+0x5a6/0xba0 net/bridge/br_input.c:424 __netif_receive_skb_core+0xf48/0x3940 net/core/dev.c:5651 __netif_receive_skb_one_core net/core/dev.c:5755 [inline] __netif_receive_skb net/core/dev.c:5870 [inline] process_backlog+0x3e5/0xae0 net/core/dev.c:6202 __napi_poll+0xd3/0x610 net/core/dev.c:6853 napi_poll net/core/dev.c:6922 [inline] net_rx_action+0x584/0xce0 net/core/dev.c:7044 handle_softirqs+0x1ae/0x630 kernel/softirq.c:603 __do_softirq+0xf/0x16 kernel/softirq.c:641 do_softirq+0xa6/0x100 kernel/softirq.c:485 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:412 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_do_batch+0x5c6/0xd20 kernel/rcu/tree.c:2586 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline] rcu_nocb_cb_kthread+0x4dc/0xac0 kernel/rcu/tree_nocb.h:957 kthread+0x2c7/0x370 kernel/kthread.c:389 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 net_ratelimit: 40814 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:86:35:3e:bc:79:9f, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:86:35:3e:bc:79:9f, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:86:35:3e:bc:79:9f, vlan:0) net_ratelimit: 53832 callbacks suppressed bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:86:35:3e:bc:79:9f, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:86:35:3e:bc:79:9f, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)