rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=5aac/1/0x4000000000000000 softirq=10391/10392 fqs=6 (t=10500 jiffies g=10529 q=27 ncpus=2) rcu: rcu_preempt kthread starved for 10486 jiffies! g10529 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:27840 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4609 Comm: syz.3.51 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:kasan_check_range+0x1ab/0x290 mm/kasan/generic.c:-1 Code: 4d 89 d6 4d 8d 56 07 4d 85 f6 4d 0f 49 d6 49 83 e2 f8 4d 29 d6 74 12 41 80 39 00 0f 85 a0 00 00 00 49 ff c1 49 ff ce 75 ee 5b <41> 5e 41 5f c3 84 db 75 61 f7 c3 00 ff 00 00 75 5e f7 c3 00 00 ff RSP: 0018:ffffc900001e0c28 EFLAGS: 00000056 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8162f659 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8e1f6ca8 RBP: ffffc900001e0d48 R08: dffffc0000000000 R09: fffffbfff1c3ed96 R10: fffffbfff1c3ed96 R11: 1ffffffff1c3ed95 R12: 0000000000000001 R13: 1ffff9200003c194 R14: 0000000000000001 R15: dffffc0000000001 FS: 00007fee791926c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000006b000 CR3: 0000000028992000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:72 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:444 [inline] cpu_online include/linux/cpumask.h:1030 [inline] trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0xd9/0x490 kernel/locking/lockdep.c:5633 seqcount_lockdep_reader_access+0xc6/0x1c0 include/linux/seqlock.h:102 ktime_get_update_offsets_now+0x44/0x3e0 kernel/time/timekeeping.c:2317 hrtimer_update_base kernel/time/hrtimer.c:659 [inline] hrtimer_interrupt+0x130/0x9c0 kernel/time/hrtimer.c:1855 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline] __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 3e 9d 41 f7 48 89 df e8 96 62 42 f7 e8 b1 54 65 f7 fb bf 01 00 00 00 46 dd 35 f7 65 8b 05 c7 94 e0 75 85 c0 74 02 5b c3 e8 14 a6 de RSP: 0018:ffffc900052afb98 EFLAGS: 00000282 RAX: 4ce004b796611400 RBX: ffff888076b3e5c0 RCX: 4ce004b796611400 RDX: dffffc0000000000 RSI: ffffffff8a8c0580 RDI: 0000000000000001 RBP: ffff888076b3ea58 R08: dffffc0000000000 R09: ffffed100ed67cb9 R10: ffffed100ed67cb9 R11: 1ffff1100ed67cb8 R12: 1ffff1100ed67d4b R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000 spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x1163/0x1350 kernel/signal.c:2874 arch_do_signal_or_restart+0xb7/0x1240 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fee7838efc7 Code: ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 RSP: 002b:00007fee79192038 EFLAGS: 00000246 RAX: 0000000000000113 RBX: 00007fee785e5fa0 RCX: 00007fee7838efc9 RDX: 000000000000000a RSI: 0000000000000000 RDI: 0000000000000008 RBP: 00007fee78411f91 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fee785e6038 R14: 00007fee785e5fa0 R15: 00007ffc2241a8a8 CPU: 0 PID: 4615 Comm: syz.1.54 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:rseq_handle_notify_resume include/linux/sched.h:2333 [inline] RIP: 0010:rseq_signal_deliver include/linux/sched.h:2342 [inline] RIP: 0010:setup_rt_frame arch/x86/kernel/signal.c:773 [inline] RIP: 0010:handle_signal arch/x86/kernel/signal.c:828 [inline] RIP: 0010:arch_do_signal_or_restart+0x229/0x1240 arch/x86/kernel/signal.c:873 Code: 49 8d bc 24 78 15 00 00 be 08 00 00 00 e8 ef 65 a4 00 49 0f ba ac 24 78 15 00 00 01 e8 b0 91 5a 00 fb 4d 8d ac 24 68 15 00 00 <4c> 89 e8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ef e8 22 64 a4 00 49 RSP: 0018:ffffc900053ffca0 EFLAGS: 00000286 RAX: ff8062a6f6790200 RBX: dffffc0000000000 RCX: ff8062a6f6790200 RDX: dffffc0000000000 RSI: ffffffff8a8c0580 RDI: ffffffff8adef3a0 RBP: ffffc900053ffec0 R08: dffffc0000000000 R09: ffffed1005a17a20 R10: ffffed1005a17a20 R11: 1ffff11005a17a1f R12: ffff88802d0bbb80 R13: ffff88802d0bd0e8 R14: ffffffffffffffff R15: 0000000000000021 FS: 00007fe3acbc16c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f80dff8 CR3: 0000000072943000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe3abd8efc7 Code: ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 RSP: 002b:00007fe3acbc10e8 EFLAGS: 00000246 RAX: 00000000000000ca RBX: 00007fe3abfe5fa8 RCX: 00007fe3abd8efc9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fe3abfe5fa8 RBP: 00007fe3abfe5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe3abfe6038 R14: 00007ffd3dd8a100 R15: 00007ffd3dd8a1e8