rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=2fd/1/0x4000000000000000 softirq=31619/31620 fqs=2 (detected by 0, t=10505 jiffies, g=36289, q=311) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 11239 Comm: syz.7.1577 Not tainted 5.15.173-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:write_comp_data kernel/kcov.c:226 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x4/0x80 kernel/kcov.c:293 Code: 89 f8 89 f6 48 c7 44 0a 08 03 00 00 00 48 89 44 0a 10 48 89 74 0a 18 4c 89 44 0a 20 49 ff c1 4c 89 09 c3 0f 1f 00 4c 8b 04 24 <65> 48 8b 15 b4 f8 81 7e 65 8b 05 b5 f8 81 7e 25 00 01 ff 00 74 10 RSP: 0018:ffffc90000dd0cb8 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffff8880240e5940 RDX: 0000000000010000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff88805a7c32e8 R08: ffffffff888c1bab R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff88805a7c3000 R13: ffff88805a7c3340 R14: dffffc0000000000 R15: ffff88805a7c3328 FS: 00007ffa0566e6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d617ff8 CR3: 000000005516b000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: advance_sched+0x12b/0x940 net/sched/sch_taprio.c:721 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x598/0xcf0 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x13b/0x4b0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x78/0x80 kernel/kcov.c:302 Code: c1 e1 05 48 8d 41 28 4c 39 c8 77 1e 48 c7 44 11 08 07 00 00 00 48 89 7c 11 10 48 89 74 11 18 4c 89 44 11 20 49 ff c2 4c 89 12 0f 1f 80 00 00 00 00 41 57 41 56 41 54 53 48 8b 46 08 48 83 c0 RSP: 0018:ffffc900032efa78 EFLAGS: 00000297 RAX: 0000000000000002 RBX: 0000000000000000 RCX: ffff8880240e5940 RDX: ffffc900121a6000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900032efc70 R08: ffffffff884c871d R09: fffff5200065df63 R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc900032efbe0 R13: dffffc0000000000 R14: 1ffff9200065df58 R15: ffffc900032efae0 __copy_msghdr_from_user net/socket.c:2318 [inline] copy_msghdr_from_user net/socket.c:2369 [inline] recvmsg_copy_msghdr net/socket.c:2621 [inline] ___sys_recvmsg+0x15d/0x690 net/socket.c:2693 do_recvmmsg+0x36f/0x8f0 net/socket.c:2791 __sys_recvmmsg net/socket.c:2870 [inline] __do_sys_recvmmsg net/socket.c:2893 [inline] __se_sys_recvmmsg net/socket.c:2886 [inline] __x64_sys_recvmmsg+0x195/0x240 net/socket.c:2886 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7ffa07819809 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:00007ffa0566e058 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007ffa079df080 RCX: 00007ffa07819809 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000006 RBP: 00007ffa0788c93e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007ffa079df080 R15: 00007fffbbf47198 rcu: rcu_preempt kthread starved for 10495 jiffies! g36289 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:27064 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 0 CPU: 0 PID: 4244 Comm: kworker/0:8 Not tainted 5.15.173-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events bpf_map_free_deferred Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline] rcu_pending kernel/rcu/tree.c:3932 [inline] rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619 update_process_times+0x196/0x200 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x13b/0x4b0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x32/0x60 kernel/kcov.c:206 Code: 14 fc 81 7e 65 8b 15 15 fc 81 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 34 16 00 00 00 74 2c 8b 91 10 16 00 00 <83> fa 02 75 21 48 8b 91 18 16 00 00 48 8b 32 48 8d 7e 01 8b 89 14 RSP: 0018:ffffc90002e0f9f8 EFLAGS: 00000246 RAX: ffffffff81748c9e RBX: 1ffff920005c1f49 RCX: ffff888021b98000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90002e0faf0 R08: ffffffff81748c70 R09: ffffed10171e7679 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 0000000000000001 R14: ffffc90002e0fa48 R15: 0000000000000000 csd_lock_wait kernel/smp.c:440 [inline] smp_call_function_single+0x2ae/0x530 kernel/smp.c:758 rcu_barrier+0x262/0x4e0 kernel/rcu/tree.c:4078 htab_map_free+0x25/0x5e0 kernel/bpf/hashtab.c:1473 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287