rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=26961, q=420 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4295003730-4294993228), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g26961 f0x2 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:27568 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 13816 Comm: syz.7.1832 Not tainted 6.13.0-rc6-syzkaller-00038-g09a0fa92e5b4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:hlock_id kernel/locking/lockdep.c:430 [inline] RIP: 0010:__lock_acquire+0xb9b/0x3c40 kernel/locking/lockdep.c:5214 Code: 24 68 48 b8 00 00 00 00 00 fc ff df 48 8b 54 24 38 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 33 27 00 00 41 0f b7 47 20 <66> 25 ff 1f 66 89 04 24 41 0f b6 47 22 83 e0 03 48 83 7c 24 10 00 RSP: 0018:ffffc90000a18af0 EFLAGS: 00000046 RAX: 0000000000004000 RBX: 35a08aec8a9222e9 RCX: ffffffff81768742 RDX: 1ffff1100f10c5f2 RSI: 0000000000000008 RDI: 000000005a08aec3 RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff2dca398 R10: ffffffff96e51cc7 R11: 0000000000000002 R12: ffffed100f10c5e3 R13: ffff888078862440 R14: 0000000000000002 R15: ffff888078862f70 FS: 00007f64ed5f96c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000000 CR3: 0000000035ae8000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 debug_object_deactivate+0x13b/0x370 lib/debugobjects.c:873 debug_hrtimer_deactivate kernel/time/hrtimer.c:433 [inline] debug_deactivate kernel/time/hrtimer.c:475 [inline] __run_hrtimer kernel/time/hrtimer.c:1707 [inline] __hrtimer_run_queues+0x47c/0xae0 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire.part.0+0x155/0x380 kernel/locking/lockdep.c:5814 Code: b8 ff ff ff ff 65 0f c1 05 e0 c1 8b 7e 83 f8 01 0f 85 d0 01 00 00 9c 58 f6 c4 02 0f 85 e5 01 00 00 48 85 ed 0f 85 b6 01 00 00 <48> b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 00 00 00 48 c7 RSP: 0018:ffffc9000554f7c8 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 1ffff92000aa9efa RCX: 00000000d439196c RDX: 0000000000000001 RSI: ffffffff8b6cdce0 RDI: ffffffff8bd1eca0 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff2dca398 R10: ffffffff96e51cc7 R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff8e1bb900 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] avc_has_perm_noaudit+0x67/0x3a0 security/selinux/avc.c:1156 avc_has_perm+0xc1/0x1c0 security/selinux/avc.c:1195 sock_has_perm+0x253/0x2f0 security/selinux/hooks.c:4634 security_socket_sendmsg+0x9b/0x240 security/security.c:4671 __sock_sendmsg net/socket.c:723 [inline] ____sys_sendmsg+0x7ec/0xc90 net/socket.c:2583 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2637 __sys_sendmsg+0x16e/0x220 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f64ec785d29 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:00007f64ed5f9038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f64ec975fa0 RCX: 00007f64ec785d29 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003 RBP: 00007f64ec801b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f64ec975fa0 R15: 00007ffdf4f1eb58