rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=31cc/1/0x4000000000000000 softirq=57344/57345 fqs=3 rcu: (detected by 1, t=10502 jiffies, g=61793, q=317 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 15717 Comm: syz.6.3081 Not tainted 6.13.0-rc6-syzkaller-00231-g77a903cd8e5a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:kasan_check_range+0x5/0x290 mm/kasan/generic.c:188 Code: c2 88 06 8e e8 6c b6 e3 ff 90 0f 0b 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 <41> 57 41 56 41 54 53 b0 01 48 85 f6 0f 84 a0 01 00 00 4c 8d 04 37 RSP: 0018:ffffc90000007660 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 000000000000006c RCX: ffffffff817abe22 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff94271888 RBP: 0000000000000000 R08: ffffffff94271887 R09: 1ffffffff284e310 R10: dffffc0000000000 R11: fffffbfff284e311 R12: 0000000000000001 R13: ffff88802f7ec728 R14: 0000000000000001 R15: ffff88802f7ec728 FS: 00007fcffe41f6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcffe3fdf98 CR3: 0000000033a58000 CR4: 00000000003526f0 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] check_wait_context kernel/locking/lockdep.c:4875 [inline] __lock_acquire+0x8a2/0x2100 kernel/locking/lockdep.c:5176 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 debug_object_activate+0x17f/0x580 lib/debugobjects.c:818 debug_hrtimer_activate kernel/time/hrtimer.c:428 [inline] debug_activate kernel/time/hrtimer.c:469 [inline] enqueue_hrtimer+0x30/0x3c0 kernel/time/hrtimer.c:1076 __run_hrtimer kernel/time/hrtimer.c:1756 [inline] __hrtimer_run_queues+0x6cb/0xd30 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:variable_ffs arch/x86/include/asm/bitops.h:321 [inline] RIP: 0010:handle_softirqs+0x1ef/0x9b0 kernel/softirq.c:549 Code: 00 00 00 45 0f b7 e4 48 c7 c7 80 93 09 8c e8 e8 4f 5f 0a 65 66 c7 05 36 0b a2 7e 00 00 e8 99 62 45 00 fb 49 c7 c6 c0 b0 60 8e ff ff ff ff 41 0f bc c4 41 89 c7 41 ff c7 0f 84 0a 04 00 00 44 RSP: 0018:ffffc90000007e20 EFLAGS: 00000282 RAX: 9c5cf3945e003200 RBX: ffffc90000007ee0 RCX: ffffffff817b27ea RDX: dffffc0000000000 RSI: ffffffff8c0a98e0 RDI: ffffffff8c5edd60 RBP: ffffc90000007f50 R08: ffffffff942718b7 R09: 1ffffffff284e316 R10: dffffc0000000000 R11: fffffbfff284e317 R12: 0000000000000040 R13: 0000000000000000 R14: ffffffff8e60b0c0 R15: 1ffff11005efd780 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline] sysvec_call_function_single+0xa3/0xc0 arch/x86/kernel/smp.c:266 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5853 Code: 2b 00 74 08 4c 89 f7 e8 6a 99 88 00 f6 44 24 61 02 0f 85 85 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:ffffc90003d9f7a0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920007b3f00 RCX: ffff88802f7ec6d8 RDX: dffffc0000000000 RSI: ffffffff8c0aaae0 RDI: ffffffff8c5edd60 RBP: ffffc90003d9f8f0 R08: ffffffff942718b7 R09: 1ffffffff284e316 R10: dffffc0000000000 R11: fffffbfff284e317 R12: 1ffff920007b3efc R13: dffffc0000000000 R14: ffffc90003d9f800 R15: 0000000000000246 __might_fault+0xc6/0x120 mm/memory.c:6751 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x2a/0xc0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] copy_msghdr_from_user+0xae/0x680 net/socket.c:2513 recvmsg_copy_msghdr net/socket.c:2769 [inline] ___sys_recvmsg net/socket.c:2841 [inline] do_recvmmsg+0x3bd/0xab0 net/socket.c:2940 __sys_recvmmsg net/socket.c:3014 [inline] __do_sys_recvmmsg net/socket.c:3037 [inline] __se_sys_recvmmsg net/socket.c:3030 [inline] __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3030 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcffd585d29 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:00007fcffe41f038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007fcffd776080 RCX: 00007fcffd585d29 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000006 RBP: 00007fcffd601b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fcffd776080 R15: 00007ffcbaace9d8 rcu: rcu_preempt kthread starved for 10496 jiffies! g61793 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:24600 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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: CPU: 1 UID: 0 PID: 14999 Comm: kworker/u8:2 Not tainted 6.13.0-rc6-syzkaller-00231-g77a903cd8e5a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x19f3/0x2c60 kernel/smp.c:884 Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 c6 e6 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 71 e2 0b 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 55 e2 RSP: 0018:ffffc900126976e0 EFLAGS: 00000293 RAX: ffffffff81938f8b RBX: 1ffff110170c8c65 RCX: ffff888035e38000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900126978e0 R08: ffffffff81938f5a R09: 1ffffffff284e310 R10: dffffc0000000000 R11: fffffbfff284e311 R12: dffffc0000000000 R13: ffff8880b8646328 R14: ffff8880b873f940 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fede3aa56c0 CR3: 000000000e736000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1051 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2114 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2522 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xbc/0x260 mm/kfence/core.c:849 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244