[v6.1] INFO: rcu detected stall in mrp_join_timer (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f6e38ae624cf Linux 6.1.158
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1718797c580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7eb38bd5021fec61
dashboard link: https://syzkaller.appspot.com/bug?extid=e4c6a43ae3bed911b96a
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/0d8305ca1c94/disk-f6e38ae6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8bc85383c07b/vmlinux-f6e38ae6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d337081bce56/bzImage-f6e38ae6.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e4c6a4...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2658 jiffies s: 273957 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 26569 Comm: syz.8.5796 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x13/0x60 kernel/kcov.c:216
Code: 48 8b 3d 80 96 9e 0c 48 89 de 5b e9 f7 65 4f 00 00 00 cc cc 00 00 cc 48 8b 04 24 65 48 8b 0d d4 98 81 7e 65 8b 15 d5 98 81 7e <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00
RSP: 0018:ffffc90000006f98 EFLAGS: 00000097
RAX: ffffffff818a71be RBX: 0000000000000000 RCX: ffff888078ced940
RDX: 0000000000010103 RSI: 0000000000000000 RDI: 0000000000000008
RBP: ffffc90000007098 R08: ffffffff8f9f7008 R09: ffffffff8f9f7018
R10: ffffffff8f9f7010 R11: ffffffff8f9f7003 R12: 0000000000000000
R13: ffff888079270498 R14: ffff8880792704a8 R15: 0000000000000001
FS: 00007f3b1fd8e6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff8d20a8d58 CR3: 0000000063d09000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 00002000000000c0 DR2: 0000000000000000
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
<IRQ>
__bpf_prog_run include/linux/filter.h:597 [inline]
bpf_prog_run include/linux/filter.h:610 [inline]
bpf_prog_run_array include/linux/bpf.h:1668 [inline]
trace_call_bpf+0x3de/0x680 kernel/trace/bpf_trace.c:135
perf_trace_run_bpf_submit+0x79/0x1c0 kernel/events/core.c:9997
perf_trace_lock_acquire+0x329/0x3c0 include/trace/events/lock.h:24
trace_lock_acquire include/trace/events/lock.h:24 [inline]
lock_acquire+0x441/0x490 kernel/locking/lockdep.c:5633
seqcount_lockdep_reader_access+0xc6/0x1c0 include/linux/seqlock.h:102
timekeeping_get_delta kernel/time/timekeeping.c:254 [inline]
timekeeping_get_ns kernel/time/timekeeping.c:388 [inline]
ktime_get+0x7b/0x270 kernel/time/timekeeping.c:848
hrtimer_forward_now include/linux/hrtimer.h:509 [inline]
perf_swevent_hrtimer+0x435/0x500 kernel/events/core.c:10932
__run_hrtimer kernel/time/hrtimer.c:1747 [inline]
__hrtimer_run_queues+0x515/0xd60 kernel/time/hrtimer.c:1811
hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1873
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
__sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc90000007a20 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 54a1f181d71f9000
RDX: 0000000000000000 RSI: ffffffff8a8c1700 RDI: ffffffff8adef760
RBP: ffffc90000007b28 R08: dffffc0000000000 R09: fffffbfff215c465
R10: fffffbfff215c465 R11: 1ffffffff215c464 R12: 0000000000000000
R13: 1ffff92000000f50 R14: 0000000000000246 R15: dffffc0000000000
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
mrp_join_timer+0x24/0x170 net/802/mrp.c:603
call_timer_fn+0x1a0/0x670 kernel/time/timer.c:1700
expire_timers kernel/time/timer.c:1751 [inline]
__run_timers+0x529/0x7d0 kernel/time/timer.c:2022
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2035
handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
__do_softirq kernel/softirq.c:630 [inline]
invoke_softirq kernel/softirq.c:470 [inline]
__irq_exit_rcu+0x12f/0x220 kernel/softirq.c:679
irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
sysvec_irq_work+0x9d/0xc0 arch/x86/kernel/irq_work.c:17
</IRQ>
<TASK>
asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:finish_task_switch+0x26a/0x8f0 kernel/sched/core.c:5123
Code: 0f 84 3b 01 00 00 48 85 db 0f 85 5a 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 e0 6d c9 08 e8 6b b7 2e 00 fb 4c 8b 65 c0 <49> 8d bc 24 f8 15 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc900040b77b8 EFLAGS: 00000286
RAX: 54a1f181d71f9000 RBX: 0000000000000000 RCX: 54a1f181d71f9000
RDX: dffffc0000000000 RSI: ffffffff8a8c0580 RDI: ffffffff8adef760
RBP: ffffc900040b7810 R08: dffffc0000000000 R09: ffffed10171c6afa
R10: ffffed10171c6afa R11: 1ffff110171c6af9 R12: ffff888078ced940
R13: dffffc0000000000 R14: ffff888027c21dc0 R15: ffff8880b8e3b590
context_switch kernel/sched/core.c:5247 [inline]
__schedule+0x10f4/0x40b0 kernel/sched/core.c:6561
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
irqentry_exit+0x63/0x70 kernel/entry/common.c:439
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:put_cpu_partial+0x17c/0x250 mm/slub.c:2670
Code: 00 00 00 9c 8f 44 24 10 f7 44 24 10 00 02 00 00 75 3b f7 c5 00 02 00 00 75 40 4d 85 e4 74 0b 48 89 df 4c 89 e6 e8 74 11 00 00 <65> 48 8b 04 25 28 00 00 00 48 3b 44 24 18 0f 85 b4 00 00 00 48 83
RSP: 0018:ffffc900040b7b20 EFLAGS: 00000246
RAX: 54a1f181d71f9000 RBX: ffff888019a56500 RCX: 54a1f181d71f9000
RDX: dffffc0000000000 RSI: ffffffff8a8c0580 RDI: ffffffff8adef760
RBP: 0000000000000282 R08: dffffc0000000000 R09: ffffed10171c6afa
R10: ffffed10171c6afa R11: 1ffff110171c6af9 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888078ced940 R15: ffff8880b8e44420
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
slab_alloc_node mm/slub.c:3359 [inline]
slab_alloc mm/slub.c:3367 [inline]
__kmem_cache_alloc_lru mm/slub.c:3374 [inline]
kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383
sk_prot_alloc+0x57/0x210 net/core/sock.c:2046
sk_alloc+0x36/0x340 net/core/sock.c:2108
unix_create1+0xb3/0x710 net/unix/af_unix.c:-1
unix_create+0x143/0x1f0 net/unix/af_unix.c:1017
__sock_create+0x4a2/0x940 net/socket.c:1550
sock_create net/socket.c:1606 [inline]
__sys_socketpair+0x232/0x540 net/socket.c:1737
__do_sys_socketpair net/socket.c:1786 [inline]
__se_sys_socketpair net/socket.c:1783 [inline]
__x64_sys_socketpair+0x97/0xb0 net/socket.c:1783
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f3b1ef8f749
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:00007f3b1fd8e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007f3b1f1e5fa0 RCX: 00007f3b1ef8f749
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000001
RBP: 00007f3b1f013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000040 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3b1f1e6038 R14: 00007f3b1f1e5fa0 R15: 00007fff54d8cf98
</TASK>


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