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

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 8ce36b2849ef Linux 6.1.163
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1236f6e6580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f0605c5af04d7603
dashboard link: https://syzkaller.appspot.com/bug?extid=820102eeabc9e10b0df0
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1189f15a580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15253652580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6cee9de046d6/disk-8ce36b28.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e0455cf6949c/vmlinux-8ce36b28.xz
kernel image: https://storage.googleapis.com/syzbot-assets/fb16f4beed74/bzImage-8ce36b28.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+820102...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2666 jiffies s: 3565 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: 4348 Comm: kworker/0:9 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: rcu_gp process_srcu
RIP: 0010:match_held_lock+0x5/0xb0 kernel/locking/lockdep.c:5108
Code: c7 c7 c0 10 8c 8a 48 c7 c6 00 11 8c 8a e8 23 49 21 f7 0f 0b eb b6 e8 ca fa ff ff 66 2e 0f 1f 84 00 00 00 00 00 b9 01 00 00 00 <48> 39 77 10 74 6c 53 81 7f 20 00 00 10 00 72 5f 48 8b 46 08 48 85
RSP: 0018:ffffc90000007650 EFLAGS: 00000097
RAX: 0000000000000000 RBX: ffff88807b878000 RCX: 0000000000000001
RDX: ffff88807b878000 RSI: ffffffff8cb2d620 RDI: ffff88807b878ae0
RBP: 00000000ffffffff R08: dffffc0000000000 R09: 1ffffffff215ea48
R10: dffffc0000000000 R11: fffffbfff215ea49 R12: 0000000000000000
R13: 0000000000000046 R14: ffffffff8cb2d620 R15: ffff88807b878ae0
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3bd8f4da08 CR3: 000000005e630000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
__lock_is_held kernel/locking/lockdep.c:5403 [inline]
lock_is_held_type+0xa6/0x190 kernel/locking/lockdep.c:5705
trace_call_bpf+0x19e/0x6b0 kernel/trace/bpf_trace.c:135
perf_trace_run_bpf_submit+0x79/0x1c0 kernel/events/core.c:9997
perf_trace_preemptirq_template+0x268/0x320 include/trace/events/preemptirq.h:14
trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40
trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44
asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:rcu_read_unlock_special+0x7f/0x510 kernel/rcu/tree_plugin.h:685
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 92 31 95 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc900000079c0 EFLAGS: 00000206
RAX: 0c33a682d6e6f300 RBX: 1ffff92000000f40 RCX: 0c33a682d6e6f300
RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0d20
RBP: ffffc90000007ac0 R08: ffffffff90af525f R09: 1ffffffff215ea4b
R10: dffffc0000000000 R11: fffffbfff215ea4c R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8e3b900 R15: 0000000000000001
__rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
rcu_read_unlock include/linux/rcupdate.h:823 [inline]
process_backlog+0x410/0x6f0 net/core/dev.c:6037
__napi_poll+0xc0/0x460 net/core/dev.c:6603
napi_poll net/core/dev.c:6670 [inline]
net_rx_action+0x5dd/0xb20 net/core/dev.c:6784
handle_softirqs+0x2a1/0x930 kernel/softirq.c:596
__do_softirq kernel/softirq.c:630 [inline]
invoke_softirq kernel/softirq.c:470 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:delay_tsc+0x57/0xc0 arch/x86/lib/delay.c:79
Code: 90 49 89 d7 49 c1 e7 20 49 09 c7 4d 29 f7 49 39 df 73 53 bf 01 00 00 00 e8 76 d8 38 f7 65 8b 05 37 5d e2 75 85 c0 74 1c f3 90 <bf> 01 00 00 00 e8 cf d6 38 f7 e8 fa 97 0c 00 39 c5 75 0e 0f 01 f9
RSP: 0018:ffffc90003207ab8 EFLAGS: 00000286
RAX: 0000000080000000 RBX: 0000000000002af9 RCX: 0000000000000000
RDX: 0000000000000037 RSI: ffffffff8adf0d00 RDI: 00000000ffffffff
RBP: 0000000000000000 R08: ffffffff8e1fcc2f R09: 1ffffffff1c3f985
R10: dffffc0000000000 R11: fffffbfff1c3f986 R12: ffff8880b8f44000
R13: dffffc0000000000 R14: 000000379d5ff98f R15: 00000000000021df
try_check_zero+0x3bf/0x3e0 kernel/rcu/srcutree.c:975
srcu_advance_state kernel/rcu/srcutree.c:1549 [inline]
process_srcu+0x1a0/0x1180 kernel/rcu/srcutree.c:1651
process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>


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