rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2633 jiffies s: 90305 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: 15816 Comm: syz.3.4240 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:182 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x2a/0x60 kernel/kcov.c:216 Code: 48 8b 04 24 65 48 8b 0d 14 41 80 7e 65 8b 15 15 41 80 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00 00 <74> 2c 8b 91 f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b RSP: 0018:ffffc900001e0338 EFLAGS: 00000046 RAX: ffffffff8139f10e RBX: 0000000000000001 RCX: ffff88807dccda00 RDX: 0000000000000100 RSI: ffffffff8adf5dc0 RDI: ffffffff8adf5d80 RBP: 0000000000000001 R08: dffffc0000000000 R09: 1ffffffff2162048 R10: dffffc0000000000 R11: fffffbfff2162049 R12: dffffc0000000000 R13: 0000000000000008 R14: ffffffff8139eec8 R15: ffff88813fff92e0 FS: 00007fcf39d596c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2ff19ff8 CR3: 000000002e9d1000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000b6e DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rcu_read_unlock_sched include/linux/rcupdate.h:902 [inline] pfn_valid include/linux/mmzone.h:1867 [inline] __virt_addr_valid+0x3ce/0x540 arch/x86/mm/physaddr.c:65 kasan_addr_to_slab+0x9/0xc0 mm/kasan/common.c:36 __kasan_record_aux_stack+0xf/0xc0 mm/kasan/generic.c:471 irq_work_queue_on+0x10f/0x260 kernel/irq_work.c:140 rcu_read_unlock_special+0x3c9/0x510 kernel/rcu/tree_plugin.h:678 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426 rcu_read_unlock include/linux/rcupdate.h:823 [inline] __perf_event_output kernel/events/core.c:7741 [inline] perf_event_output_forward+0x271/0x2f0 kernel/events/core.c:7750 __perf_event_overflow+0x457/0x630 kernel/events/core.c:9496 perf_swevent_overflow kernel/events/core.c:9579 [inline] perf_swevent_event+0x315/0x570 kernel/events/core.c:9630 perf_tp_event+0x36b/0xc10 kernel/events/core.c:10064 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10032 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 a2 7c 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:ffffc900001e0c40 EFLAGS: 00000206 RAX: 4c6850abfd7c5e00 RBX: 1ffff9200003c190 RCX: 4c6850abfd7c5e00 RDX: dffffc0000000000 RSI: ffffffff8a8c17a0 RDI: ffffffff8adf5de0 RBP: ffffc900001e0d30 R08: ffffffff90b102e7 R09: 1ffffffff216205c R10: dffffc0000000000 R11: fffffbfff216205d R12: 0000000000000246 R13: dffffc0000000000 R14: ffff8880b8f3bb00 R15: 0000000000000002 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426 rcu_read_unlock include/linux/rcupdate.h:823 [inline] rebalance_domains+0x86f/0x9d0 kernel/sched/fair.c:11051 handle_softirqs+0x291/0x910 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:kasan_mem_to_shadow include/linux/kasan.h:60 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x4e/0x290 mm/kasan/generic.c:189 Code: e8 2f 41 81 f8 ff ff 01 00 0f 82 fa 01 00 00 49 bc 01 00 00 00 00 fc ff df 49 89 fe 49 c1 ee 03 49 ba 00 00 00 00 00 fc ff df <4f> 8d 1c 16 4c 8d 44 3e ff 4d 89 c1 49 c1 e9 03 4b 8d 1c 21 49 89 RSP: 0018:ffffc900033e74d8 EFLAGS: 00000a02 RAX: 1ffffd40003e6501 RBX: ffffea0001f32900 RCX: ffffffff81c7a9eb RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea0001f32900 RBP: dffffc0000000000 R08: 000000000001ffff R09: 1ffffd40003e6520 R10: dffffc0000000000 R11: fffff940003e6521 R12: dffffc0000000001 R13: 0000000000000002 R14: 1ffffd40003e6520 R15: 1ffffd40003e6521 instrument_atomic_read include/linux/instrumented.h:72 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] PageCompound include/linux/page-flags.h:297 [inline] free_pages_prepare mm/page_alloc.c:1456 [inline] free_pcp_prepare mm/page_alloc.c:1537 [inline] free_unref_page_prepare+0x4ab/0x9e0 mm/page_alloc.c:3414 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3509 free_slab mm/slub.c:2036 [inline] discard_slab mm/slub.c:2042 [inline] __unfreeze_partials+0x188/0x1e0 mm/slub.c:2591 put_cpu_partial+0x17c/0x250 mm/slub.c:2667 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:306 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x490 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_lru+0x182/0x2e0 mm/slub.c:3390 __d_alloc+0x2e/0x6e0 fs/dcache.c:1774 d_alloc fs/dcache.c:1854 [inline] d_alloc_parallel+0xdc/0x1590 fs/dcache.c:2647 lookup_open fs/namei.c:3415 [inline] open_last_lookups fs/namei.c:3558 [inline] path_openat+0x949/0x2f10 fs/namei.c:3788 do_filp_open+0x1ee/0x420 fs/namei.c:3818 do_sys_openat2+0x14b/0x4f0 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: 0033:0x7fcf38d9e019 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:00007fcf39d59028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fcf39025fa0 RCX: 00007fcf38d9e019 RDX: 00000000000026e1 RSI: 0000200000000080 RDI: ffffffffffffff9c RBP: 00007fcf38e3500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcf39026038 R14: 00007fcf39025fa0 R15: 00007ffc23810f18