INFO: task syz.3.207:950 blocked for more than 123 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.207 state:D stack:0 pid:950 tgid:948 ppid:289 flags:0x00004004
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
rcu_barrier+0x415/0x530 kernel/rcu/tree.c:4657
flush_rcu_work+0x71/0x90 kernel/workqueue.c:4292
kvfree_rcu_barrier+0x23c/0x2f0 kernel/rcu/tree.c:3955
kmem_cache_destroy+0x32/0x170 mm/slab_common.c:490
p9_client_destroy+0x42b/0x480 net/9p/client.c:1088
v9fs_session_init+0x13b7/0x1820 fs/9p/v9fs.c:490
v9fs_mount+0xd7/0xa00 fs/9p/vfs_super.c:122
legacy_get_tree+0x106/0x1b0 fs/fs_context.c:662
vfs_get_tree+0x9e/0x290 fs/super.c:1817
do_new_mount+0x251/0xb40 fs/namespace.c:3537
path_mount+0x688/0x1050 fs/namespace.c:3864
do_mount fs/namespace.c:3877 [inline]
__do_sys_mount fs/namespace.c:4087 [inline]
__se_sys_mount+0x2bd/0x480 fs/namespace.c:4064
__x64_sys_mount+0xc3/0xf0 fs/namespace.c:4064
x64_sys_call+0x2021/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:166
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: 0033:0x7f713ef8efc9
RSP: 002b:00007f713fe26038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f713f1e5fa0 RCX: 00007f713ef8efc9
RDX: 0000200000000000 RSI: 0000200000000300 RDI: 0000000000000000
RBP: 00007f713f011f91 R08: 0000200000000340 R09: 0000000000000000
R10: 0000000001814800 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f713f1e6038 R14: 00007f713f1e5fa0 R15: 00007ffdf148e7d8
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 20 Comm: rcuop/0 Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:ip6_mc_input+0x4/0x670 net/ipv6/ip6_input.c:497
Code: 49 89 c7 e9 fa fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 b8 c2 a9 23 73 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec a0 00
RSP: 0018:ffffc90000007500 EFLAGS: 00000257
RAX: ffffffff84e2b14a RBX: ffff888110853640 RCX: ffff888103663900
RDX: 0000000000000100 RSI: 0000000000800000 RDI: ffff888110853640
RBP: ffffc90000007530 R08: 0000000000000000 R09: ffff888110853640
R10: 0000000000000000 R11: ffffffff84e2fdf0 R12: dffffc0000000000
R13: 1ffff1102210a6d3 R14: ffff88810a7ff668 R15: 1ffff110214ffecd
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005576fec83b98 CR3: 000000010b70a000 CR4: 00000000003526b0
Call Trace:
NF_HOOK include/linux/netfilter.h:317 [inline]
ipv6_rcv+0xed/0x220 net/ipv6/ip6_input.c:309
__netif_receive_skb_one_core net/core/dev.c:5769 [inline]
__netif_receive_skb net/core/dev.c:5882 [inline]
netif_receive_skb_internal net/core/dev.c:5968 [inline]
netif_receive_skb+0x147/0x7b0 net/core/dev.c:6027
br_netif_receive_skb net/bridge/br_input.c:30 [inline]
NF_HOOK include/linux/netfilter.h:317 [inline]
br_pass_frame_up+0x126/0x1c0 net/bridge/br_input.c:70
br_handle_frame_finish+0x12d9/0x1720 net/bridge/br_input.c:221
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+0xf4b/0x3940 net/core/dev.c:5663
__netif_receive_skb_one_core net/core/dev.c:5767 [inline]
__netif_receive_skb net/core/dev.c:5882 [inline]
process_backlog+0x3e5/0xae0 net/core/dev.c:6218
__napi_poll+0xd3/0x610 net/core/dev.c:6869
napi_poll net/core/dev.c:6938 [inline]
net_rx_action+0x584/0xce0 net/core/dev.c:7060
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: 87963 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 veth0_to_bridge with own address as source address (addr:00:00:00:00:67:5f, 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 veth0_to_bridge with own address as source address (addr:00:00:00:00:67:5f, 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:00:00:00:00:67:5f, 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 veth0_to_bridge with own address as source address (addr:76:72:f2:24:f3:84, 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 veth0_to_bridge with own address as source address (addr:00:00:00:00:67:5f, vlan:0)