[v6.6] INFO: rcu detected stall in ip_list_rcv

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4791134e4aeb Linux 6.6.118
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1295d4c2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=12606d4b8832c7e4
dashboard link: https://syzkaller.appspot.com/bug?extid=70204a71afdd800448da
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d5853385c5d5/disk-4791134e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/13d5cf580b4d/vmlinux-4791134e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a9536fd663f0/bzImage-4791134e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+70204a...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 13444 jiffies s: 49793 root: 0x2/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 12620 Comm: syz.1.1822 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:check_region_inline mm/kasan/generic.c:172 [inline]
RIP: 0010:kasan_check_range+0x26/0x290 mm/kasan/generic.c:187
Code: cc cc cc cc 66 0f 1f 00 b0 01 48 85 f6 0f 84 b8 01 00 00 55 41 57 41 56 41 55 41 54 53 4c 8d 04 37 49 39 f8 0f 82 5a 02 00 00 <49> 89 f9 49 c1 e9 2f 41 81 f9 ff ff 01 00 0f 82 46 02 00 00 49 89
RSP: 0018:ffffc900001eecc8 EFLAGS: 00000012
RAX: 0000000000000001 RBX: ffff88802af0bc00 RCX: ffffffff8167b5a4
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90da9508
RBP: 0000000000000008 R08: ffffffff90da9510 R09: 1ffffffff21b52a1
R10: dffffc0000000000 R11: fffffbfff21b52a2 R12: 0000000000000100
R13: dffffc0000000000 R14: ffff88802af0c898 R15: 0000000000000067
FS: 00007fe99d1a06c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100000000 CR3: 000000006646d000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
<IRQ>
instrument_atomic_read include/linux/instrumented.h:68 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
hlock_class kernel/locking/lockdep.c:228 [inline]
mark_lock+0x94/0x320 kernel/locking/lockdep.c:4656
mark_usage kernel/locking/lockdep.c:4599 [inline]
__lock_acquire+0xd49/0x7c80 kernel/locking/lockdep.c:5091
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0xa3/0xe0 kernel/locking/spinlock.c:170
__run_hrtimer kernel/time/hrtimer.c:1754 [inline]
__hrtimer_run_queues+0x5e3/0xc40 kernel/time/hrtimer.c:1814
hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
__sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x51/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:212
Code: 00 0f 0b 0f 1f 80 00 00 00 00 f3 0f 1e fa 53 48 89 fb e8 13 00 00 00 48 8b 3d 5c 05 c5 0c 48 89 de 5b e9 43 9d 56 00 cc cc cc <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0d f0 24 7e 7e 65 8b 15 f1 24 7e
RSP: 0018:ffffc900001ef4f8 EFLAGS: 00000a06
RAX: f2f2f200f1f1f1f1 RBX: 000000000001e3d6 RCX: 1ffffffff19a9349
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900001ef5b8 R08: ffffffff90da95c7 R09: 1ffffffff21b52b8
R10: dffffc0000000000 R11: fffffbfff21b52b9 R12: 0027a10ce5f3b5ce
R13: 000001fb63109b96 R14: 1ffff9200003dea0 R15: dffffc0000000000
seqcount_lockdep_reader_access+0x74/0x1c0 include/linux/seqlock.h:97
timekeeping_get_delta kernel/time/timekeeping.c:254 [inline]
timekeeping_get_ns kernel/time/timekeeping.c:388 [inline]
ktime_get_with_offset+0x103/0x330 kernel/time/timekeeping.c:891
ktime_get_real include/linux/timekeeping.h:79 [inline]
net_timestamp_set net/core/dev.c:2194 [inline]
dev_queue_xmit_nit+0x8d2/0xbb0 net/core/dev.c:2344
xmit_one net/core/dev.c:3615 [inline]
dev_hard_start_xmit+0x148/0x740 net/core/dev.c:3635
sch_direct_xmit+0x252/0x4a0 net/sched/sch_generic.c:345
__dev_xmit_skb net/core/dev.c:3856 [inline]
__dev_queue_xmit+0x173e/0x35a0 net/core/dev.c:4391
neigh_output include/net/neighbour.h:543 [inline]
ip_finish_output2+0xd21/0x11d0 net/ipv4/ip_output.c:235
dst_output include/net/dst.h:467 [inline]
ip_local_out net/ipv4/ip_output.c:129 [inline]
__ip_queue_xmit+0x10aa/0x1a10 net/ipv4/ip_output.c:535
__tcp_transmit_skb+0x1c97/0x32a0 net/ipv4/tcp_output.c:1422
tcp_ack_snd_check net/ipv4/tcp_input.c:5728 [inline]
tcp_rcv_established+0xb00/0x1cf0 net/ipv4/tcp_input.c:6174
tcp_v4_do_rcv+0x4ed/0xb80 net/ipv4/tcp_ipv4.c:1734
tcp_v4_rcv+0x2334/0x2a50 net/ipv4/tcp_ipv4.c:2166
ip_protocol_deliver_rcu+0x20e/0x3f0 net/ipv4/ip_input.c:205
ip_local_deliver_finish+0x2ca/0x510 net/ipv4/ip_input.c:233
NF_HOOK+0x303/0x390 include/linux/netfilter.h:304
dst_input include/net/dst.h:477 [inline]
ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline]
ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline]
ip_sublist_rcv+0xa38/0xd20 net/ipv4/ip_input.c:639
ip_list_rcv+0x3e3/0x430 net/ipv4/ip_input.c:674
__netif_receive_skb_list_ptype net/core/dev.c:5651 [inline]
__netif_receive_skb_list_core+0x578/0x740 net/core/dev.c:5699
__netif_receive_skb_list net/core/dev.c:5751 [inline]
netif_receive_skb_list_internal+0x91b/0xc60 net/core/dev.c:5842
gro_normal_list include/net/gro.h:451 [inline]
gro_normal_one include/net/gro.h:464 [inline]
napi_skb_finish net/core/gro.c:573 [inline]
napi_gro_receive+0x565/0xb00 net/core/gro.c:603
receive_buf+0x218c/0x3780 drivers/net/virtio_net.c:1870
virtnet_receive drivers/net/virtio_net.c:2155 [inline]
virtnet_poll+0x61f/0x1180 drivers/net/virtio_net.c:2229
__napi_poll+0xc0/0x460 net/core/dev.c:6612
napi_poll net/core/dev.c:6679 [inline]
net_rx_action+0x5ea/0xbf0 net/core/dev.c:6815
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:generic_exec_single+0x476/0x4f0 kernel/smp.c:418
Code: 75 11 e8 cd e6 0a 00 48 85 db 75 16 e8 c3 e6 0a 00 eb 15 e8 bc e6 0a 00 e8 c7 73 f4 08 48 85 db 74 ea e8 ad e6 0a 00 fb 31 c0 <48> c7 44 24 20 0e 36 e0 45 4b c7 04 2c 00 00 00 00 66 43 c7 44 2c
RSP: 0018:ffffc9000362fa00 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000200 RCX: ffff88802af0bc00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000362fad0 R08: ffffffff90da95ff R09: 1ffffffff21b52bf
R10: dffffc0000000000 R11: fffffbfff21b52c0 R12: 1ffff920006c5f44
R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff920006c5f65
smp_call_function_single+0x352/0x580 kernel/smp.c:647
task_function_call kernel/events/core.c:120 [inline]
perf_install_in_context+0x591/0x8e0 kernel/events/core.c:2948
__do_sys_perf_event_open kernel/events/core.c:12915 [inline]
__se_sys_perf_event_open+0x17fa/0x1c20 kernel/events/core.c:12567
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe99c38f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe99d1a0038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007fe99c5e5fa0 RCX: 00007fe99c38f749
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000480
RBP: 00007fe99c413f91 R08: 000000000000000b R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe99c5e6038 R14: 00007fe99c5e5fa0 R15: 00007ffe6da2c4e8
</TASK>


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