rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2673 jiffies s: 83237 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: 17750 Comm: syz.3.3455 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x0/0x80 kernel/kcov.c:314 Code: 28 4d 39 ca 77 22 89 ff 89 f6 49 ff c0 4c 89 01 48 c7 44 11 08 03 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 90 <48> 8b 04 24 65 48 8b 15 44 f7 7f 7e 65 8b 0d 45 f7 7f 7e 81 e1 00 RSP: 0018:ffffc900000079e8 EFLAGS: 00000082 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 6b85e0308737be00 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000008 RBP: 0000000000000000 R08: ffff8880b8e3580b R09: 1ffff110171c6b01 R10: dffffc0000000000 R11: ffffed10171c6b02 R12: ffffffff8cb7fba0 R13: dffffc0000000000 R14: ffffc90000007aa0 R15: ffffc90000007ac0 FS: 00007f33a705f6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000485dd000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: perf_swevent_get_recursion_context+0x22/0x150 kernel/events/core.c:9753 perf_trace_buf_alloc+0x54/0x300 kernel/trace/trace_event_perf.c:414 perf_trace_preemptirq_template+0x143/0x320 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 d2 33 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:ffffc90000007c20 EFLAGS: 00000206 RAX: 6b85e0308737be00 RBX: 1ffff92000000f8c RCX: 6b85e0308737be00 RDX: dffffc0000000000 RSI: ffffffff8a8c10a0 RDI: ffffffff8adf0d20 RBP: ffffc90000007d08 R08: ffff8880b8e3580b R09: 1ffff110171c6b01 R10: dffffc0000000000 R11: ffffed10171c6b02 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] rebalance_domains+0x8da/0xa10 kernel/sched/fair.c:11051 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 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:49 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:178 [inline] RIP: 0010:unwind_next_frame+0x137b/0x20b0 arch/x86/kernel/unwind_orc.c:448 Code: 00 00 fc ff df 0f b6 04 08 84 c0 75 27 49 63 06 4c 01 f0 49 8d 4e 04 48 39 e8 4c 0f 46 e9 49 8d 46 fc 4c 0f 47 e0 4d 0f 46 fe <4d> 39 e5 76 a8 e9 d6 ee ff ff 44 89 f1 80 e1 07 80 c1 03 38 c1 7c RSP: 0018:ffffc90005de73f0 EFLAGS: 00000293 RAX: ffffffff8e36b484 RBX: ffffc90005de74c8 RCX: ffffffff8e36b48c RDX: ffffffff8ea9fa0a RSI: ffffffff8e36b46c RDI: ffffffff81391adf RBP: ffffffff81d2d9ca R08: 000000000000000a R09: 0000000000000002 R10: dffffc0000000000 R11: fffff52000bbcea5 R12: ffffffff8e36b490 R13: ffffffff8e36b48c R14: ffffffff8e36b488 R15: ffffffff8e36b488 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:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:329 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 kmem_cache_zalloc include/linux/slab.h:689 [inline] __alloc_file+0x25/0x230 fs/file_table.c:138 alloc_empty_file+0x90/0x180 fs/file_table.c:187 path_openat+0x10f/0x2ee0 fs/namei.c:3777 do_filp_open+0x1f1/0x430 fs/namei.c:3818 do_sys_openat2+0x150/0x4b0 fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1347 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f33a619c819 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:00007f33a705f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f33a6416090 RCX: 00007f33a619c819 RDX: 0000000000000002 RSI: 0000200000000200 RDI: ffffffffffffffff RBP: 00007f33a6232c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f33a6416128 R14: 00007f33a6416090 R15: 00007ffd129ac048