rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10500 ticks this GP) idle=0c5c/1/0x4000000000000000 softirq=9931/9931 fqs=42 (t=10502 jiffies g=10733 q=206 ncpus=2) rcu: rcu_preempt kthread starved for 10419 jiffies! g10733 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:26864 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x99/0x3b0 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: 0 Comm: swapper/1 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline] RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 ef 2f 01 03 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc900001e0e38 EFLAGS: 00000046 RAX: 000000000009791a RBX: 000000000009791a RCX: 0000000000000838 RDX: 0000000000000000 RSI: 000000000009791a RDI: 0000000000000838 RBP: 0000000000000000 R08: ffffffff8e1fc32f R09: 1ffffffff1c3f865 R10: dffffc0000000000 R11: fffffbfff1c3f866 R12: dffffc0000000000 R13: 00000000100053e2 R14: ffffffff8c64fb40 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f22265fd58 CR3: 000000005b8c9000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: apic_write arch/x86/include/asm/apic.h:394 [inline] lapic_next_event+0x5b/0x70 arch/x86/kernel/apic/apic.c:478 clockevents_program_event+0x1bc/0x310 kernel/time/clockevents.c:334 hrtimer_interrupt+0x59d/0x9c0 kernel/time/hrtimer.c:1886 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:default_idle+0xb/0x10 arch/x86/kernel/process.c:742 Code: 48 89 df e8 a7 10 9d f7 e9 44 ff ff ff e8 7d 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 87 5d 50 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48 RSP: 0018:ffffc90000177de8 EFLAGS: 000002c6 RAX: d85efee99e5e3500 RBX: ffffffff8a3651a7 RCX: d85efee99e5e3500 RDX: 0000000000000001 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0c20 RBP: ffffc90000177f20 R08: ffff8880b8f3580b R09: 1ffff110171e6b01 R10: dffffc0000000000 R11: ffffed10171e6b02 R12: 1ffff9200002efc8 R13: dffffc0000000000 R14: ffff88813fed9dc0 R15: 0000000000000001 default_idle_call+0x84/0xc0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x20d/0x5a0 kernel/sched/idle.c:303 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401 start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xcf/0xdb CPU: 0 PID: 4468 Comm: syz.4.13 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:35 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:106 [inline] RIP: 0010:lock_acquire+0x166/0x4a0 kernel/locking/lockdep.c:5658 Code: 0f 85 2f 02 00 00 41 83 3e 00 0f 85 18 01 00 00 43 c6 44 3d 08 00 48 c7 84 24 a0 00 00 00 00 00 00 00 9c 8f 84 24 a0 00 00 00 <4c> 8b b4 24 a0 00 00 00 43 c6 44 3d 08 f8 fa 48 c7 c7 00 1f 8c 8a RSP: 0018:ffffc900049ffa00 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 2ef78937fb200800 RDX: 0000000000000000 RSI: ffffffff8adf0c00 RDI: ffffffff8adf0bc0 RBP: ffffc900049ffb10 R08: ffffffff8e1fc32f R09: 1ffffffff1c3f865 R10: dffffc0000000000 R11: fffffbfff1c3f866 R12: 0000000000000000 R13: 1ffff9200093ff4c R14: ffff88802be5289c R15: dffffc0000000000 FS: 00007f7ad17706c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000058 CR3: 000000007e033000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __fs_reclaim_acquire mm/page_alloc.c:4719 [inline] fs_reclaim_acquire+0x6d/0x100 mm/page_alloc.c:4733 might_alloc include/linux/sched/mm.h:271 [inline] slab_pre_alloc_hook+0x2a/0x310 mm/slab.h:710 slab_alloc_node mm/slub.c:3279 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc+0x56/0x2f0 mm/slub.c:3383 getname_kernel+0x56/0x2f0 fs/namei.c:227 kern_path+0x19/0x50 fs/namei.c:2613 unix_find_bsd net/unix/af_unix.c:1047 [inline] unix_find_other+0x102/0x800 net/unix/af_unix.c:1108 unix_stream_connect+0x259/0xd20 net/unix/af_unix.c:1501 __sys_connect_file net/socket.c:2010 [inline] __sys_connect+0x3cb/0x450 net/socket.c:2027 __do_sys_connect net/socket.c:2037 [inline] __se_sys_connect net/socket.c:2034 [inline] __x64_sys_connect+0x76/0x80 net/socket.c:2034 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: 0033:0x7f7ad099aeb9 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:00007f7ad1770028 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007f7ad0c15fa0 RCX: 00007f7ad099aeb9 RDX: 000000000000006e RSI: 0000200000000000 RDI: 0000000000000005 RBP: 00007f7ad0a08c1f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7ad0c16038 R14: 00007f7ad0c15fa0 R15: 00007ffda9e5f108