rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10500 ticks this GP) idle=c7f/1/0x4000000000000000 softirq=38076/38076 fqs=0 (t=10501 jiffies g=55969 q=76) rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g55969 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=23165 rcu: rcu_preempt kthread starved for 10504 jiffies! g55969 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:28696 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x800 kernel/rcu/tree.c:1957 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2130 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 0 CPU: 0 PID: 20403 Comm: syz-executor.5 Not tainted 5.15.0-rc4-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+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 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:3880 [inline] rcu_sched_clock_irq.cold+0x98/0x746 kernel/rcu/tree.c:2599 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:kasan_set_track mm/kasan/common.c:47 [inline] RIP: 0010:set_alloc_info mm/kasan/common.c:434 [inline] RIP: 0010:____kasan_kmalloc mm/kasan/common.c:513 [inline] RIP: 0010:____kasan_kmalloc mm/kasan/common.c:472 [inline] RIP: 0010:__kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:522 Code: c0 74 27 48 01 d8 49 89 c4 74 1f 65 48 8b 04 25 40 f0 01 00 8b 80 60 05 00 00 89 ef 41 89 04 24 e8 1c ff ff ff 41 89 44 24 04 <48> 89 d8 5b 5d 41 5c 41 5d c3 e8 c8 2b 00 00 48 85 db 0f 85 65 ff RSP: 0018:ffffc90018237898 EFLAGS: 00000286 RAX: 00000000ae8001c7 RBX: ffff888031863180 RCX: ffffffff89400068 RDX: 000000000005e06e RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000cc0 R08: 0000000091992076 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880318631a0 R13: 0000000000000020 R14: dffffc0000000000 R15: ffff88807e93e000 kmalloc include/linux/slab.h:591 [inline] tty_alloc_file drivers/tty/tty_io.c:187 [inline] tty_open+0x140/0x1000 drivers/tty/tty_io.c:2140 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4c8/0x11d0 fs/open.c:822 do_open fs/namei.c:3428 [inline] path_openat+0x1c9a/0x2740 fs/namei.c:3561 do_filp_open+0x1aa/0x400 fs/namei.c:3588 do_sys_openat2+0x16d/0x4d0 fs/open.c:1200 do_sys_open fs/open.c:1216 [inline] __do_sys_openat fs/open.c:1232 [inline] __se_sys_openat fs/open.c:1227 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1227 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f6495f738d9 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:00007f64934ea188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f6496077f60 RCX: 00007f6495f738d9 RDX: 0000000000000802 RSI: 0000000020000840 RDI: ffffffffffffff9c RBP: 00007f6495fcdcb4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc9e38a20f R14: 00007f64934ea300 R15: 0000000000022000 NMI backtrace for cpu 0 CPU: 0 PID: 20403 Comm: syz-executor.5 Not tainted 5.15.0-rc4-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+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x25e/0x3f0 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:3880 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2599 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:kasan_set_track mm/kasan/common.c:47 [inline] RIP: 0010:set_alloc_info mm/kasan/common.c:434 [inline] RIP: 0010:____kasan_kmalloc mm/kasan/common.c:513 [inline] RIP: 0010:____kasan_kmalloc mm/kasan/common.c:472 [inline] RIP: 0010:__kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:522 Code: c0 74 27 48 01 d8 49 89 c4 74 1f 65 48 8b 04 25 40 f0 01 00 8b 80 60 05 00 00 89 ef 41 89 04 24 e8 1c ff ff ff 41 89 44 24 04 <48> 89 d8 5b 5d 41 5c 41 5d c3 e8 c8 2b 00 00 48 85 db 0f 85 65 ff RSP: 0018:ffffc90018237898 EFLAGS: 00000286 RAX: 00000000ae8001c7 RBX: ffff888031863180 RCX: ffffffff89400068 RDX: 000000000005e06e RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000cc0 R08: 0000000091992076 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880318631a0 R13: 0000000000000020 R14: dffffc0000000000 R15: ffff88807e93e000 kmalloc include/linux/slab.h:591 [inline] tty_alloc_file drivers/tty/tty_io.c:187 [inline] tty_open+0x140/0x1000 drivers/tty/tty_io.c:2140 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4c8/0x11d0 fs/open.c:822 do_open fs/namei.c:3428 [inline] path_openat+0x1c9a/0x2740 fs/namei.c:3561 do_filp_open+0x1aa/0x400 fs/namei.c:3588 do_sys_openat2+0x16d/0x4d0 fs/open.c:1200 do_sys_open fs/open.c:1216 [inline] __do_sys_openat fs/open.c:1232 [inline] __se_sys_openat fs/open.c:1227 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1227 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f6495f738d9 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:00007f64934ea188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f6496077f60 RCX: 00007f6495f738d9 RDX: 0000000000000802 RSI: 0000000020000840 RDI: ffffffffffffff9c RBP: 00007f6495fcdcb4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc9e38a20f R14: 00007f64934ea300 R15: 0000000000022000 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 20399 Comm: syz-executor.3 Not tainted 5.15.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:lookup_object lib/debugobjects.c:198 [inline] RIP: 0010:debug_object_deactivate lib/debugobjects.c:737 [inline] RIP: 0010:debug_object_deactivate+0x14f/0x300 lib/debugobjects.c:723 Code: ed 74 44 49 bc 00 00 00 00 00 fc ff df 48 8d 7d 18 83 c3 01 48 89 f8 48 c1 e8 03 42 80 3c 20 00 0f 85 1e 01 00 00 4c 3b 7d 18 <74> 74 48 89 e8 48 c1 e8 03 42 80 3c 20 00 0f 85 22 01 00 00 48 8b RSP: 0018:ffffc90000dc0d58 EFLAGS: 00000046 RAX: 1ffff110093907d1 RBX: 0000000000000001 RCX: ffffffff815bc380 RDX: 1ffffffff2096737 RSI: 0000000000000016 RDI: ffff888049c83e88 RBP: ffff888049c83e70 R08: ffffffff904b39a8 R09: 0000000000000003 R10: fffff520001b8199 R11: 0000000000000000 R12: dffffc0000000000 R13: ffffffff898df0a0 R14: 1ffff920001b81ad R15: ffff88801e684d60 FS: 00007f19b7ffc700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f792a6a13a4 CR3: 0000000056354000 CR4: 0000000000350ee0 Call Trace: 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+0x3f8/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__schedule+0x948/0x26f0 kernel/sched/core.c:6166 Code: df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 cb 17 00 00 4c 89 ef 4d 89 7c 24 10 4c 89 fe e8 c0 9f c9 f7 48 89 c7 e8 e8 53 19 f8 <48> 8b 8d 38 ff ff ff 48 b8 00 00 00 00 00 fc ff df 48 c7 04 01 00 RSP: 0018:ffffc900181b77c0 EFLAGS: 00000206 RAX: 0000000000ec698b RBX: 0000000000000000 RCX: 1ffffffff1adc5a9 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900181b7888 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff817c2848 R11: 0000000000000000 R12: ffff8880b9d31a40 R13: ffff8880b9d32500 R14: 0000000000000001 R15: ffff8880416c1c80 schedule+0xd3/0x270 kernel/sched/core.c:6366 tty_open+0x885/0x1000 drivers/tty/tty_io.c:2153 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4c8/0x11d0 fs/open.c:822 do_open fs/namei.c:3428 [inline] path_openat+0x1c9a/0x2740 fs/namei.c:3561 do_filp_open+0x1aa/0x400 fs/namei.c:3588 do_sys_openat2+0x16d/0x4d0 fs/open.c:1200 do_sys_open fs/open.c:1216 [inline] __do_sys_openat fs/open.c:1232 [inline] __se_sys_openat fs/open.c:1227 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1227 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f19baa858d9 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:00007f19b7ffc188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f19bab89f60 RCX: 00007f19baa858d9 RDX: 0000000000000802 RSI: 0000000020000840 RDI: ffffffffffffff9c RBP: 00007f19baadfcb4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe3694888f R14: 00007f19b7ffc300 R15: 0000000000022000 sched: RT throttling activated ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 74 27 je 0x29 2: 48 01 d8 add %rbx,%rax 5: 49 89 c4 mov %rax,%r12 8: 74 1f je 0x29 a: 65 48 8b 04 25 40 f0 mov %gs:0x1f040,%rax 11: 01 00 13: 8b 80 60 05 00 00 mov 0x560(%rax),%eax 19: 89 ef mov %ebp,%edi 1b: 41 89 04 24 mov %eax,(%r12) 1f: e8 1c ff ff ff callq 0xffffff40 24: 41 89 44 24 04 mov %eax,0x4(%r12) * 29: 48 89 d8 mov %rbx,%rax <-- trapping instruction 2c: 5b pop %rbx 2d: 5d pop %rbp 2e: 41 5c pop %r12 30: 41 5d pop %r13 32: c3 retq 33: e8 c8 2b 00 00 callq 0x2c00 38: 48 85 db test %rbx,%rbx 3b: 0f .byte 0xf 3c: 85 65 ff test %esp,-0x1(%rbp)