rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10500 ticks this GP) idle=4bf/1/0x4000000000000000 softirq=6605/6605 fqs=0 (t=10500 jiffies g=6961 q=718) rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g6961 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=3742 rcu: rcu_preempt kthread starved for 10500 jiffies! g6961 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:25944 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xb72/0x1460 kernel/sched/core.c:6253 schedule+0x12b/0x1f0 kernel/sched/core.c:6326 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x1fd/0x770 kernel/rcu/tree.c:1955 rcu_gp_kthread+0xa5/0x350 kernel/rcu/tree.c:2128 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 0 CPU: 0 PID: 3898 Comm: syz-executor.3 Not tainted 5.16.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_check_gp_kthread_starvation+0x1ff/0x270 kernel/rcu/tree_stall.h:481 print_cpu_stall kernel/rcu/tree_stall.h:625 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3878 [inline] rcu_sched_clock_irq+0x1e2e/0x2bc0 kernel/rcu/tree.c:2597 update_process_times+0x197/0x200 kernel/time/timer.c:1785 tick_sched_handle kernel/time/tick-sched.c:226 [inline] tick_sched_timer+0x27d/0x420 kernel/time/tick-sched.c:1428 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4cb/0xa60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:196 Code: 84 00 00 00 00 00 0f 1f 40 00 be 0d 00 00 00 48 c7 c7 e0 af b5 8c e8 8f 66 4a 00 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0c 25 c0 6f 02 00 65 8b 15 a4 f1 7d 7e f7 c2 RSP: 0018:ffffc900052e7478 EFLAGS: 00000202 RAX: 0000000000000002 RBX: 0000000000000001 RCX: 0000000080000000 RDX: ffff88803457ba00 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900052e75d0 R08: ffffffff81aeef20 R09: fffff940001f4d21 R10: fffff940001f4d21 R11: 0000000000000000 R12: 0000000000003089 R13: dffffc0000000000 R14: ffffea0000fa6940 R15: ffff8880338b0ee0 xa_entry include/linux/xarray.h:1182 [inline] xas_next include/linux/xarray.h:1822 [inline] filemap_get_read_batch+0x799/0xb40 mm/filemap.c:2350 filemap_get_pages mm/filemap.c:2552 [inline] filemap_read+0x66e/0x2a00 mm/filemap.c:2642 call_read_iter include/linux/fs.h:2156 [inline] generic_file_splice_read+0x482/0x760 fs/splice.c:311 do_splice_to fs/splice.c:796 [inline] splice_direct_to_actor+0x45f/0xd00 fs/splice.c:870 do_splice_direct+0x291/0x3e0 fs/splice.c:979 do_sendfile+0x6fe/0x1040 fs/read_write.c:1245 __do_sys_sendfile64 fs/read_write.c:1310 [inline] __se_sys_sendfile64+0x171/0x1d0 fs/read_write.c:1296 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f2c1694fe99 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2c152c5168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f2c16a62f60 RCX: 00007f2c1694fe99 RDX: 0000000000000000 RSI: 0000000000000014 RDI: 0000000000000006 RBP: 00007f2c169a9ff1 R08: 0000000000000000 R09: 0000000000000000 R10: 00008400fffffffb R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc770a813f R14: 00007f2c152c5300 R15: 0000000000022000 NMI backtrace for cpu 0 CPU: 0 PID: 3898 Comm: syz-executor.3 Not tainted 5.16.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x22d/0x390 kernel/rcu/tree_stall.h:343 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3878 [inline] rcu_sched_clock_irq+0x1e33/0x2bc0 kernel/rcu/tree.c:2597 update_process_times+0x197/0x200 kernel/time/timer.c:1785 tick_sched_handle kernel/time/tick-sched.c:226 [inline] tick_sched_timer+0x27d/0x420 kernel/time/tick-sched.c:1428 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4cb/0xa60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:196 Code: 84 00 00 00 00 00 0f 1f 40 00 be 0d 00 00 00 48 c7 c7 e0 af b5 8c e8 8f 66 4a 00 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0c 25 c0 6f 02 00 65 8b 15 a4 f1 7d 7e f7 c2 RSP: 0018:ffffc900052e7478 EFLAGS: 00000202 RAX: 0000000000000002 RBX: 0000000000000001 RCX: 0000000080000000 RDX: ffff88803457ba00 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900052e75d0 R08: ffffffff81aeef20 R09: fffff940001f4d21 R10: fffff940001f4d21 R11: 0000000000000000 R12: 0000000000003089 R13: dffffc0000000000 R14: ffffea0000fa6940 R15: ffff8880338b0ee0 xa_entry include/linux/xarray.h:1182 [inline] xas_next include/linux/xarray.h:1822 [inline] filemap_get_read_batch+0x799/0xb40 mm/filemap.c:2350 filemap_get_pages mm/filemap.c:2552 [inline] filemap_read+0x66e/0x2a00 mm/filemap.c:2642 call_read_iter include/linux/fs.h:2156 [inline] generic_file_splice_read+0x482/0x760 fs/splice.c:311 do_splice_to fs/splice.c:796 [inline] splice_direct_to_actor+0x45f/0xd00 fs/splice.c:870 do_splice_direct+0x291/0x3e0 fs/splice.c:979 do_sendfile+0x6fe/0x1040 fs/read_write.c:1245 __do_sys_sendfile64 fs/read_write.c:1310 [inline] __se_sys_sendfile64+0x171/0x1d0 fs/read_write.c:1296 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f2c1694fe99 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2c152c5168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f2c16a62f60 RCX: 00007f2c1694fe99 RDX: 0000000000000000 RSI: 0000000000000014 RDI: 0000000000000006 RBP: 00007f2c169a9ff1 R08: 0000000000000000 R09: 0000000000000000 R10: 00008400fffffffb R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc770a813f R14: 00007f2c152c5300 R15: 0000000000022000 sched: RT throttling activated ---------------- Code disassembly (best guess): 0: 84 00 test %al,(%rax) 2: 00 00 add %al,(%rax) 4: 00 00 add %al,(%rax) 6: 0f 1f 40 00 nopl 0x0(%rax) a: be 0d 00 00 00 mov $0xd,%esi f: 48 c7 c7 e0 af b5 8c mov $0xffffffff8cb5afe0,%rdi 16: e8 8f 66 4a 00 callq 0x4a66aa 1b: c3 retq 1c: cc int3 1d: cc int3 1e: cc int3 1f: cc int3 20: cc int3 21: cc int3 22: cc int3 23: cc int3 24: cc int3 25: cc int3 26: cc int3 27: cc int3 28: cc int3 29: cc int3 * 2a: 48 8b 04 24 mov (%rsp),%rax <-- trapping instruction 2e: 65 48 8b 0c 25 c0 6f mov %gs:0x26fc0,%rcx 35: 02 00 37: 65 8b 15 a4 f1 7d 7e mov %gs:0x7e7df1a4(%rip),%edx # 0x7e7df1e2 3e: f7 .byte 0xf7 3f: c2 .byte 0xc2