rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=8c8c/1/0x4000000000000000 softirq=25239/25239 fqs=1 rcu: (detected by 0, t=10506 jiffies, g=31989, q=206 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9367 Comm: syz-executor.5 Not tainted 6.5.0-rc3-syzkaller-00018-g0b5547c51827 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023 RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline] RIP: 0010:lock_acquire+0x45f/0x510 kernel/locking/lockdep.c:5732 Code: 00 41 57 44 8b 44 24 14 8b 54 24 10 e8 ea 15 fe ff 5e 5f 65 ff 0d 79 2d 9c 7e 0f 85 37 fc ff ff e8 06 f6 98 ff e9 2d fc ff ff 1c a7 07 00 84 c0 0f 85 59 fc ff ff 0f 0b e9 52 fc ff ff 0f 0b RSP: 0018:ffffc900001e0ca0 EFLAGS: 00000047 RAX: 0000000000000001 RBX: 1ffff9200003c196 RCX: ffffffff81678877 RDX: fffffbfff1d56ffb RSI: 0000000000000008 RDI: ffffffff8eab7fd0 RBP: 0000000000000001 R08: 0000000000000000 R09: fffffbfff1d56ffa R10: ffffffff8eab7fd7 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8c9a6580 R15: 0000000000000000 FS: 00007fd4d4a8c6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000201a0030 CR3: 0000000020f47000 CR4: 0000000000350ee0 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:303 [inline] rcu_read_lock include/linux/rcupdate.h:749 [inline] advance_sched+0x67e/0xc60 net/sched/sch_taprio.c:996 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x203/0xc10 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1098 [inline] __sysvec_apic_timer_interrupt+0x14a/0x430 arch/x86/kernel/apic/apic.c:1115 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1109 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:__sanitizer_cov_trace_pc+0x57/0x70 kernel/kcov.c:213 Code: 04 16 00 00 85 c0 74 2b 8b 82 e0 15 00 00 83 f8 02 75 20 48 8b 8a e8 15 00 00 8b 92 e4 15 00 00 48 8b 01 48 83 c0 01 48 39 d0 <73> 07 48 89 01 48 89 34 c1 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f RSP: 0018:ffffc9000401fcc0 EFLAGS: 00000246 RAX: 0000000000040000 RBX: 0000000000000002 RCX: ffffc9001589a000 RDX: 0000000000040000 RSI: ffffffff881ddf65 RDI: 0000000000000005 RBP: 0000000000000002 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000006828 R13: 0000000000000000 R14: 00000000201a0ac0 R15: 0000000000010106 do_recvmmsg+0x295/0x740 net/socket.c:2849 __sys_recvmmsg net/socket.c:2928 [inline] __do_sys_recvmmsg net/socket.c:2951 [inline] __se_sys_recvmmsg net/socket.c:2944 [inline] __x64_sys_recvmmsg+0x235/0x290 net/socket.c:2944 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fd4d3c7cb29 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:00007fd4d4a8c0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007fd4d3d9c050 RCX: 00007fd4d3c7cb29 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000005 RBP: 00007fd4d3cc847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007fd4d3d9c050 R15: 00007ffe155f73f8 rcu: rcu_preempt kthread starved for 10500 jiffies! g31989 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:28224 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0xee1/0x59f0 kernel/sched/core.c:6710 schedule+0xe7/0x1b0 kernel/sched/core.c:6786 schedule_timeout+0x157/0x2c0 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x1ec/0xa50 kernel/rcu/tree.c:1609 rcu_gp_kthread+0x249/0x380 kernel/rcu/tree.c:1808 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296 RIP: 0000:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 9252 Comm: kworker/u4:22 Not tainted 6.5.0-rc3-syzkaller-00018-g0b5547c51827 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:296 [inline] RIP: 0010:smp_call_function_many_cond+0x4db/0x1570 kernel/smp.c:835 Code: 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 fc 4c 89 fd 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 1c 5f 0b 00 f3 90 41 0f b6 04 24 <40> 38 c5 7c 08 84 c0 0f 85 3c 0e 00 00 8b 43 08 31 ff 83 e0 01 41 RSP: 0018:ffffc900038ff938 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9943020 RCX: 0000000000000000 RDX: ffff88807d9f5940 RSI: ffffffff817b1194 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffed1017328605 R13: 0000000000000001 R14: ffff8880b983d580 R15: ffff8880b9943028 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 000000000c776000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1003 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2001 [inline] text_poke_bp_batch+0x250/0x780 arch/x86/kernel/alternative.c:2211 text_poke_flush arch/x86/kernel/alternative.c:2402 [inline] text_poke_flush arch/x86/kernel/alternative.c:2399 [inline] text_poke_finish+0x1a/0x30 arch/x86/kernel/alternative.c:2409 arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x32e/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+0xf4/0x250 mm/kfence/core.c:823 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2597 worker_thread+0x687/0x1110 kernel/workqueue.c:2748 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296 RIP: 0000:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000