rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (3 ticks this GP) idle=7e14/1/0x4000000000000000 softirq=53249/53249 fqs=2 rcu: (detected by 0, t=10502 jiffies, g=74897, q=43 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 16296 Comm: syz-executor.4 Not tainted 6.4.0-rc2-next-20230515-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023 RIP: 0010:kasan_check_range+0xeb/0x190 mm/kasan/generic.c:187 Code: 74 f2 48 89 c2 b8 01 00 00 00 48 85 d2 74 27 49 39 d1 75 17 49 0f be 01 41 83 e2 07 49 39 c2 73 0a 5b b8 01 00 00 00 5d 41 5c 44 89 c2 e8 ec ee ff ff 83 f0 01 5b 5d 41 5c c3 48 85 d2 74 e1 RSP: 0018:ffffc900001e0968 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 1ffff9200003c135 RCX: ffffffff8165429e RDX: fffffbfff22a75a1 RSI: 0000000000000008 RDI: ffffffff9153ad00 RBP: 0000000000000100 R08: 0000000000000000 R09: fffffbfff22a75a0 R10: ffffffff9153ad07 R11: 0000000000000000 R12: ffff88801374e430 R13: 0000000000000008 R14: 0000000000000001 R15: ffff88801374e450 FS: 00007f6ac365f700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020374030 CR3: 00000000762a5000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] hlock_class kernel/locking/lockdep.c:228 [inline] mark_lock.part.0+0xee/0x1970 kernel/locking/lockdep.c:4634 mark_lock kernel/locking/lockdep.c:4620 [inline] mark_usage kernel/locking/lockdep.c:4577 [inline] __lock_acquire+0x907/0x5f30 kernel/locking/lockdep.c:5042 lock_acquire.part.0+0x11c/0x370 kernel/locking/lockdep.c:5705 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 debug_object_deactivate lib/debugobjects.c:774 [inline] debug_object_deactivate+0x105/0x300 lib/debugobjects.c:762 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline] debug_deactivate kernel/time/hrtimer.c:481 [inline] __run_hrtimer kernel/time/hrtimer.c:1653 [inline] __hrtimer_run_queues+0x3f3/0xa30 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x320/0x7b0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x14a/0x430 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x92/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:200 Code: 26 b9 8e 02 66 0f 1f 44 00 00 f3 0f 1e fa 48 8b be a8 01 00 00 e8 b0 ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 0f 1e fa 65 8b 05 0d 98 7f 7e 89 c1 48 8b 34 24 81 e1 00 01 00 RSP: 0018:ffffc90016037a00 EFLAGS: 00000246 RAX: 0000000000040000 RBX: 0000000000000000 RCX: ffffc9000d7a5000 RDX: 0000000000040000 RSI: ffffffff8805fe85 RDI: ffffc900160377c0 RBP: ffffc90016037db0 R08: 0000000000000001 R09: fffff52002c06ef8 R10: ffffc900160377c7 R11: 0000000000000001 R12: 0000000000000000 R13: 000000000000dd1f R14: 0000000000000002 R15: ffffc90016037df4 ____sys_recvmsg+0x218/0x5a0 net/socket.c:2724 ___sys_recvmsg+0xf2/0x180 net/socket.c:2764 do_recvmmsg+0x25e/0x6f0 net/socket.c:2858 __sys_recvmmsg net/socket.c:2937 [inline] __do_sys_recvmmsg net/socket.c:2960 [inline] __se_sys_recvmmsg net/socket.c:2953 [inline] __x64_sys_recvmmsg+0x20f/0x260 net/socket.c:2953 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f6ac288c169 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6ac365f168 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f6ac29ac050 RCX: 00007f6ac288c169 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000005 RBP: 00007f6ac28e7ca1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff45494d8f R14: 00007f6ac365f300 R15: 0000000000022000 rcu: rcu_preempt kthread starved for 10498 jiffies! g74897 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:27880 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5343 [inline] __schedule+0x1d15/0x5790 kernel/sched/core.c:6669 schedule+0xde/0x1a0 kernel/sched/core.c:6745 schedule_timeout+0x14e/0x2b0 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1609 rcu_gp_kthread+0x23a/0x360 kernel/rcu/tree.c:1808 kthread+0x344/0x440 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 6245 Comm: kworker/u4:20 Not tainted 6.4.0-rc2-next-20230515-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:285 [inline] RIP: 0010:smp_call_function_many_cond+0x684/0x1240 kernel/smp.c:828 Code: 89 ee e8 2f 41 0b 00 85 ed 74 48 48 8b 44 24 08 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 f4 83 c5 03 e8 ee 44 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 81 09 00 00 8b 43 08 31 RSP: 0018:ffffc90004a57948 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9943220 RCX: 0000000000000000 RDX: ffff88802b255940 RSI: ffffffff8178dec2 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffffed1017328645 R13: 0000000000000001 R14: dffffc0000000000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0f1cfa8000 CR3: 000000000c571000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x5a/0xa0 kernel/smp.c:996 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1925 [inline] text_poke_bp_batch+0x237/0x770 arch/x86/kernel/alternative.c:2125 text_poke_flush arch/x86/kernel/alternative.c:2316 [inline] text_poke_flush arch/x86/kernel/alternative.c:2313 [inline] text_poke_finish+0x1a/0x30 arch/x86/kernel/alternative.c:2323 arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x32f/0x410 kernel/jump_label.c:829 static_key_enable_cpuslocked+0x1b5/0x270 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate mm/kfence/core.c:831 [inline] toggle_allocation_gate+0xf8/0x230 mm/kfence/core.c:823 process_one_work+0x99a/0x15e0 kernel/workqueue.c:2407 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2554 kthread+0x344/0x440 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308