rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (1 GPs behind) idle=5d84/1/0x4000000000000000 softirq=11186/11187 fqs=5 (t=10502 jiffies g=11665 q=554 ncpus=2) rcu: rcu_preempt kthread starved for 10493 jiffies! g11665 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:26496 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4474 Comm: syz.0.27 Not tainted 6.1.140-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:87 [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+0x81/0x290 mm/kasan/generic.c:189 Code: 03 4e 8d 14 3b 4d 89 d6 4d 29 ce 49 83 fe 10 7f 26 4d 85 f6 0f 84 39 01 00 00 48 f7 d3 4c 01 db 41 80 39 00 0f 85 c1 01 00 00 <49> ff c1 48 ff c3 75 ee e9 1c 01 00 00 44 89 cb 83 e3 07 0f 84 b5 RSP: 0018:ffffc90003577980 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffffffffffffffff RCX: ffffffff81636be5 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8dfe8028 RBP: ffffc90003577ab0 R08: dffffc0000000000 R09: fffffbfff1bfd005 R10: fffffbfff1bfd006 R11: 1ffffffff1bfd005 R12: dffffc0000000000 R13: dffffc0000000000 R14: 0000000000000001 R15: dffffc0000000001 FS: 0000555556c7a500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000006b000 CR3: 000000007c365000 CR4: 00000000003506f0 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_release include/trace/events/lock.h:69 [inline] lock_release+0xc5/0x910 kernel/locking/lockdep.c:5673 __clear_user arch/x86/include/asm/uaccess_64.h:96 [inline] copy_fpstate_to_sigframe+0x1a6/0xcb0 arch/x86/kernel/fpu/signal.c:216 get_sigframe arch/x86/kernel/signal.c:297 [inline] __setup_rt_frame arch/x86/kernel/signal.c:472 [inline] setup_rt_frame arch/x86/kernel/signal.c:784 [inline] handle_signal arch/x86/kernel/signal.c:828 [inline] arch_do_signal_or_restart+0x610/0x1230 arch/x86/kernel/signal.c:873 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 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: 0033:0x7fd992b8e969 Code: 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 01 48 RSP: 002b:00007ffe70ec1ce8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007fd992db5fa0 RCX: 00007fd992b8e969 RDX: 000020000006b000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fd992c10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd992db5fa0 R14: 00007fd992db5fa0 R15: 0000000000000004 CPU: 1 PID: 4473 Comm: syz.2.26 Not tainted 6.1.140-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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 ce 2e 4a f7 48 89 df e8 26 f4 4a f7 e8 91 f6 6d f7 fb bf 01 00 00 00 36 71 3e f7 65 8b 05 d7 32 e9 75 85 c0 74 02 5b c3 e8 24 44 e7 RSP: 0018:ffffc900034d7bb8 EFLAGS: 00000286 RAX: 4728406e15b6b700 RBX: ffff888077511bc0 RCX: 4728406e15b6b700 RDX: dffffc0000000000 RSI: ffffffff8a6c0000 RDI: 0000000000000001 RBP: ffff888077512058 R08: dffffc0000000000 R09: ffffed100eea2379 R10: ffffed100eea2379 R11: 1ffff1100eea2378 R12: 1ffff1100eea240b R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000 FS: 000055556c34a500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000006b000 CR3: 0000000029919000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x1163/0x1350 kernel/signal.c:2874 arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 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: 0033:0x7f4e4098e969 Code: 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 01 48 RSP: 002b:00007fff3c468d18 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007f4e40bb5fa0 RCX: 00007f4e4098e969 RDX: 000020000006b000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f4e40a10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4e40bb5fa0 R14: 00007f4e40bb5fa0 R15: 0000000000000004 sched: RT throttling activated