rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-....: (1 GPs behind) idle=95d/1/0x4000000000000002 softirq=16867/16868 fqs=2101 
	(detected by 1, t=10506 jiffies, g=21369, q=290)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7486 Comm: syz.0.1157 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:171 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:226 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x23/0x80 kernel/kcov.c:299
Code: ff c1 48 89 0a c3 90 48 8b 04 24 65 48 8b 0d 34 5c 89 7e 65 8b 15 35 5c 89 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 <83> b9 34 16 00 00 00 74 4e 8b 91 10 16 00 00 83 fa 03 75 43 48 8b
RSP: 0018:ffffc90000007260 EFLAGS: 00000046
RAX: ffffffff81988908 RBX: ffffc90000007358 RCX: ffff88802aba1dc0
RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffffc90000007340 R08: ffff88802aba1dc7 R09: 1ffff110055743b8
R10: dffffc0000000000 R11: ffffed10055743b9 R12: 0000000000000001
R13: ffff8880b90351c8 R14: 1ffff1100bf6c577 R15: 0000000000000007
FS:  00007f252267d6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbd9aee0018 CR3: 000000005b888000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000200000000300
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 perf_swevent_event+0x1f8/0x540 kernel/events/core.c:9633
 perf_tp_event+0x324/0xbe0 kernel/events/core.c:10057
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10031
 perf_trace_preemptirq_template+0x2aa/0x360 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674
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 f2 0f 9d 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc90000007760 EFLAGS: 00000206
RAX: 3e512fd1f14fcd00 RBX: 1ffff92000000ef0 RCX: 3e512fd1f14fcd00
RDX: dffffc0000000000 RSI: ffffffff8a2b2be0 RDI: ffffffff8a7a4540
RBP: ffffc90000007840 R08: ffffffff901ef18f R09: 1ffffffff203de31
R10: dffffc0000000000 R11: fffffbfff203de32 R12: ffffffff8c323400
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 __ip_queue_xmit+0x127d/0x1c60 net/ipv4/ip_output.c:539
 __tcp_transmit_skb+0x1ca3/0x31e0 net/ipv4/tcp_output.c:1404
 tcp_delack_timer_handler+0x2f8/0x700 net/ipv4/tcp_timer.c:314
 tcp_delack_timer+0x18d/0x2f0 net/ipv4/tcp_timer.c:341
 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
 expire_timers kernel/time/timer.c:1699 [inline]
 __run_timers+0x56c/0x810 kernel/time/timer.c:1970
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
 handle_softirqs+0x336/0x830 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:30 [inline]
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:52 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:178 [inline]
RIP: 0010:unwind_next_frame+0xfb3/0x1cf0 arch/x86/kernel/unwind_orc.c:448
Code: 89 37 e9 33 01 00 00 49 89 f4 48 89 f5 4c 89 e8 48 29 e8 48 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe 4c 8d 7c 45 00 <4c> 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84
RSP: 0018:ffffc9000308f670 EFLAGS: 00000202
RAX: 0000000000000004 RBX: ffffc9000308f708 RCX: 0000000000000005
RDX: ffffffff8e0fb8f0 RSI: ffffffff8da081e8 RDI: ffffffff81351ed7
RBP: ffffffff8da08200 R08: 000000000000000c R09: 0000000000000001
R10: dffffc0000000000 R11: fffff52000611eed R12: ffffffff8da081fc
R13: ffffffff8da08214 R14: ffffffff81be388e R15: ffffffff8da08208
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1710 [inline]
 slab_free_freelist_hook+0xec/0x170 mm/slub.c:1736
 slab_free mm/slub.c:3504 [inline]
 kfree+0xef/0x2a0 mm/slub.c:4564
 tomoyo_realpath_from_path+0x5ad/0x5e0 security/tomoyo/realpath.c:291
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_number_perm+0x251/0x6b0 security/tomoyo/file.c:723
 security_file_ioctl+0x6c/0xa0 security/security.c:1617
 __do_sys_ioctl fs/ioctl.c:868 [inline]
 __se_sys_ioctl+0x48/0x170 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f2524467159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f252267d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f25246ef180 RCX: 00007f2524467159
RDX: 0000200000000380 RSI: 000000004008240b RDI: 0000000000000006
RBP: 00007f25244fe024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f25246ef218 R14: 00007f25246ef180 R15: 00007ffef80d2538
 </TASK>