INFO: task syz.3.1831:6239 blocked for more than 122 seconds.
Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1831 state:D stack:0 pid:6239 tgid:6239 ppid:290 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_timeout+0xb2/0x3a0 kernel/time/timer.c:2595
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common+0x359/0x630 kernel/sched/completion.c:127
wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
exit_aio+0x2df/0x3b0 fs/aio.c:927
__mmput+0x30/0x320 kernel/fork.c:1346
mmput+0x55/0x170 kernel/fork.c:1372
exit_mm kernel/exit.c:574 [inline]
do_exit+0x918/0x2630 kernel/exit.c:940
do_group_exit+0x22a/0x300 kernel/exit.c:1095
__do_sys_exit_group kernel/exit.c:1106 [inline]
__se_sys_exit_group kernel/exit.c:1104 [inline]
__x64_sys_exit_group+0x43/0x50 kernel/exit.c:1104
x64_sys_call+0x2ed2/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:232
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: 0033:0x7f4d6978eb69
RSP: 002b:00007ffe5fa26628 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f4d6978eb69
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe5fa2668c R08: 000000105fa2671f R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000201
R13: 00000000000927c0 R14: 0000000000023176 R15: 00007ffe5fa266e0
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0 d02c7cfa86e34ad1734bbfdc1f5f1c3ce9be47fc
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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+0x2ca/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 0 to CPUs 1:
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 20 Comm: rcuop/0 Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0 d02c7cfa86e34ad1734bbfdc1f5f1c3ce9be47fc
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:delay_tsc+0x4c/0xa0 arch/x86/lib/delay.c:90
Code: 20 48 09 c6 0f 01 f9 66 90 48 c1 e2 20 48 09 c2 48 29 f2 48 39 fa 73 44 65 ff 0d 97 18 7f 7a 74 1d f3 90 65 ff 05 8c 18 7f 7a <65> 44 8b 0d 88 18 7f 7a 45 39 c8 75 0e 0f 01 f9 66 90 eb cb e8 9b
RSP: 0018:ffffc90000230038 EFLAGS: 00000003
RAX: 000000007b0b417c RBX: ffffffff88983c00 RCX: 0000000000000001
RDX: 0000000000000130 RSI: 0000008a7b0b404c RDI: 0000000000000899
RBP: ffffc90000230038 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: ffffffff8585d0b0 R12: ffffffff889dfde0
R13: 00000000000026d2 R14: ffffffff88983c40 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe307ee7d60 CR3: 000000010b38c000 CR4: 00000000003526b0
Call Trace:
__delay arch/x86/lib/delay.c:203 [inline]
__const_udelay+0x7a/0x90 arch/x86/lib/delay.c:217
wait_for_lsr drivers/tty/serial/8250/8250_port.c:2075 [inline]
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3315 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3337 [inline]
serial8250_console_write+0x141c/0x2130 drivers/tty/serial/8250/8250_port.c:3422
univ8250_console_write+0x6f/0xb0 drivers/tty/serial/8250/8250_core.c:396
console_emit_next_record kernel/printk/printk.c:3150 [inline]
console_flush_all+0x5e6/0xaa0 kernel/printk/printk.c:3238
__console_flush_and_unlock kernel/printk/printk.c:3297 [inline]
console_unlock+0xe9/0x270 kernel/printk/printk.c:3337
vprintk_emit+0x27c/0x640 kernel/printk/printk.c:2461
vprintk_default+0x2a/0x40 kernel/printk/printk.c:2476
vprintk+0x93/0xa0 kernel/printk/printk_safe.c:73
_printk+0xd0/0x120 kernel/printk/printk.c:2486
br_fdb_update+0x604/0x680 net/bridge/br_fdb.c:904
br_handle_frame_finish+0x39c/0x1720 net/bridge/br_input.c:141
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:6206
__napi_poll+0xd0/0x610 net/core/dev.c:6857
napi_poll net/core/dev.c:6926 [inline]
net_rx_action+0x584/0xce0 net/core/dev.c:7048
handle_softirqs+0x1ab/0x630 kernel/softirq.c:621
__do_softirq+0xf/0x16 kernel/softirq.c:659
do_softirq+0xa6/0x100 kernel/softirq.c:503
__local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_do_batch+0x5c6/0xd20 kernel/rcu/tree.c:2594
nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline]
rcu_nocb_cb_kthread+0x4dc/0xac0 kernel/rcu/tree_nocb.h:957
kthread+0x2ca/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
net_ratelimit: 86861 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:1b, 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:1b, 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:1b, 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:1b, 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:1b, vlan:0)