rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-....: (0 ticks this GP) idle=c1d/1/0x4000000000000002 softirq=52955/52955 fqs=5201 (detected by 1, t=10502 jiffies, g=70253, q=1454) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 18803 Comm: syz.7.3862 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713 Code: 89 c4 48 89 e7 e8 da 4d dd ff e9 85 03 00 00 90 90 90 90 90 0f 01 ca fc 6a ff e8 85 02 00 00 48 89 c4 48 89 e7 e8 aa 52 dd ff 65 03 00 00 90 90 90 90 90 0f 01 ca fc 6a ff e8 65 02 00 00 48 RSP: 0018:ffffc90000007a58 EFLAGS: 00000082 RAX: 6acb2ffe2f369500 RBX: 0000000000000000 RCX: 6acb2ffe2f369500 RDX: dffffc0000000000 RSI: ffffffff8a2b3180 RDI: ffffffff8a7a09c0 RBP: 0000000000000000 R08: ffffffff901d815f R09: 1ffffffff203b02b R10: dffffc0000000000 R11: fffffbfff203b02c R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f3af07936c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000022000 CR3: 000000002a287000 CR4: 00000000003506f0 DR0: 0000000000000004 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: 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 cc 9c 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:ffffc90000007b00 EFLAGS: 00000206 RAX: 6acb2ffe2f369500 RBX: 1ffff92000000f64 RCX: 6acb2ffe2f369500 RDX: dffffc0000000000 RSI: ffffffff8a2b3180 RDI: ffffffff8a7a09c0 RBP: ffffc90000007be0 R08: ffffffff901d815f R09: 1ffffffff203b02b R10: dffffc0000000000 R11: fffffbfff203b02c R12: ffffffff8c323800 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] ieee80211_rx_napi+0x20f/0x390 net/mac80211/rx.c:5019 ieee80211_rx include/net/mac80211.h:4573 [inline] ieee80211_handle_queued_frames+0x105/0x1b0 net/mac80211/main.c:237 tasklet_action_common+0x2ad/0x410 kernel/softirq.c:806 handle_softirqs+0x339/0x830 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 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:preempt_schedule_irq+0xb6/0x160 kernel/sched/core.c:6799 Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 7f bf 01 00 00 00 e8 a5 c1 8c f7 e8 e0 b1 b9 f7 fb bf 01 00 00 00 65 b5 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f RSP: 0018:ffffc9000338f120 EFLAGS: 00000282 RAX: 6acb2ffe2f369500 RBX: 0000000000000000 RCX: 6acb2ffe2f369500 RDX: dffffc0000000000 RSI: ffffffff8a2b3180 RDI: 0000000000000001 RBP: ffffc9000338f1d0 R08: ffffffff901d815f R09: 1ffffffff203b02b R10: dffffc0000000000 R11: fffffbfff203b02c R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000671e24 irqentry_exit+0x63/0x70 kernel/entry/common.c:432 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:84 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [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+0x92/0x290 mm/kasan/generic.c:189 Code: 49 83 ff 10 7f 29 4d 85 ff 0f 84 38 01 00 00 4c 89 cb 48 f7 d3 4c 01 f3 41 80 3b 00 0f 85 86 01 00 00 49 ff c3 48 ff c3 75 ee 18 01 00 00 44 89 dd 83 e5 07 0f 84 b5 00 00 00 41 80 3b 00 4d RSP: 0018:ffffc9000338f290 EFLAGS: 00000256 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff815d25d6 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d8a06e8 RBP: ffffc9000338f3e0 R08: ffffffff8d8a06ef R09: 1ffffffff1b140dd R10: dffffc0000000000 R11: fffffbfff1b140de R12: dffffc0000000001 R13: 1ffff92000671e64 R14: 1ffffffff1b140dd R15: 0000000000000001 instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] cpumask_test_cpu include/linux/cpumask.h:344 [inline] cpu_online include/linux/cpumask.h:895 [inline] trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0xb6/0x400 kernel/locking/lockdep.c:5594 __fs_reclaim_acquire mm/page_alloc.c:4580 [inline] fs_reclaim_acquire+0x6d/0x100 mm/page_alloc.c:4594 prepare_alloc_pages+0x15a/0x5f0 mm/page_alloc.c:5272 __alloc_pages+0x11b/0x480 mm/page_alloc.c:5490 alloc_pages_vma+0x393/0x7c0 mm/mempolicy.c:2146 shmem_alloc_page mm/shmem.c:1586 [inline] shmem_alloc_and_acct_page+0x47f/0xbe0 mm/shmem.c:1611 shmem_getpage_gfp+0x14f4/0x2d40 mm/shmem.c:1906 shmem_getpage mm/shmem.c:151 [inline] shmem_write_begin+0xcd/0x1a0 mm/shmem.c:2474 generic_perform_write+0x2b6/0x550 mm/filemap.c:3785 __generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912 generic_file_write_iter+0xa6/0x1b0 mm/filemap.c:3944 call_write_iter include/linux/fs.h:2173 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x745/0xd60 fs/read_write.c:594 ksys_write+0x152/0x260 fs/read_write.c:647 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: 0033:0x7f3af2539e59 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:00007f3af0793028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f3af27b2fa0 RCX: 00007f3af2539e59 RDX: 00000000002a979d RSI: 0000200000000000 RDI: 0000000000000007 RBP: 00007f3af25cfd6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3af27b3038 R14: 00007f3af27b2fa0 R15: 00007fffa4f014f8