rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 ticks this GP) idle=af7c/1/0x4000000000000000 softirq=68049/68049 fqs=4 (detected by 0, t=10505 jiffies, g=98713, q=340 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 21311 Comm: syz-executor.4 Not tainted 6.1.94-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:203 Code: e8 25 00 00 00 0f 0b 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 18 f9 e8 0c 48 89 de 5b e9 67 a9 56 00 cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0d e4 db 77 7e 65 8b 15 e5 db 77 7e f7 c2 00 RSP: 0018:ffffc900001e0d58 EFLAGS: 00000002 RAX: 0000000000010001 RBX: 0000000000000001 RCX: ffff888015381dc0 RDX: ffff888015381dc0 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900001e0eb0 R08: ffffffff8179be72 R09: ffff88807e9eb340 R10: 0000000000000000 R11: dffffc0000000001 R12: 1bc16d67538d79df R13: ffff8880b992a5c0 R14: ffff8880b992a4c0 R15: dffffc0000000000 FS: 00007fa28a5ad6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555555e8f788 CR3: 000000003943e000 CR4: 00000000003526e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1652 [inline] __hrtimer_run_queues+0x31f/0xe50 kernel/time/hrtimer.c:1750 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 Code: 2b 00 74 08 4c 89 f7 e8 4f ab 77 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc9000586fb40 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000b0df74 RCX: ffffffff816b2042 RDX: dffffc0000000000 RSI: ffffffff8aec13c0 RDI: ffffffff8b3d4660 RBP: ffffc9000586fc98 R08: dffffc0000000000 R09: fffffbfff2093a47 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000b0df70 R13: dffffc0000000000 R14: ffffc9000586fba0 R15: 0000000000000246 __fs_reclaim_acquire mm/page_alloc.c:4670 [inline] fs_reclaim_acquire+0x83/0x120 mm/page_alloc.c:4684 might_alloc include/linux/sched/mm.h:271 [inline] slab_pre_alloc_hook+0x2a/0x300 mm/slab.h:710 slab_alloc_node mm/slub.c:3318 [inline] __kmem_cache_alloc_node+0x47/0x260 mm/slub.c:3437 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1045 kmalloc include/linux/slab.h:556 [inline] kvm_uevent_notify_change+0x222/0x3a0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:5728 kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:5027 [inline] kvm_dev_ioctl+0x16a8/0x1860 arch/x86/kvm/../../../virt/kvm/kvm_main.c:5051 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fa28987d0a9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa28a5ad0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fa2899b3f80 RCX: 00007fa28987d0a9 RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000003 RBP: 00007fa2898ec074 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fa2899b3f80 R15: 00007ffd1e3cb858 rcu: rcu_preempt kthread starved for 10485 jiffies! g98713 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:26712 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 16908 Comm: kworker/u4:15 Not tainted 6.1.94-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:check_kcov_mode kernel/kcov.c:184 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x32/0x60 kernel/kcov.c:207 Code: e4 db 77 7e 65 8b 15 e5 db 77 7e f7 c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 <83> fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc RSP: 0018:ffffc9000fd37598 EFLAGS: 00000246 RAX: ffffffff817f53eb RBX: 1ffff110173281b1 RCX: ffff888055240000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000fd37980 R08: ffffffff817f53b4 R09: fffffbfff2093a45 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000 R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b9940d88 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d822000 CR3: 000000000ce8e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: csd_lock_wait kernel/smp.c:424 [inline] smp_call_function_many_cond+0x1fcb/0x3460 kernel/smp.c:998 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1334 [inline] text_poke_bp_batch+0x2bb/0x940 arch/x86/kernel/alternative.c:1534 text_poke_flush arch/x86/kernel/alternative.c:1725 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1732 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x12e/0x250 kernel/jump_label.c:177 static_key_enable+0x16/0x20 kernel/jump_label.c:190 toggle_allocation_gate+0xbf/0x480 mm/kfence/core.c:804 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308