rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10498 ticks this GP) idle=c2d/1/0x4000000000000000 softirq=101401/101401 fqs=0 (t=10500 jiffies g=145981 q=170) rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g145981 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=74322 rcu: rcu_preempt kthread starved for 10500 jiffies! g145981 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28712 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xa9a/0x4900 kernel/sched/core.c:6253 schedule+0xd2/0x260 kernel/sched/core.c:6326 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128 kthread+0x405/0x4f0 kernel/kthread.c:327 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 1 CPU: 1 PID: 14744 Comm: syz-executor.5 Not tainted 5.16.0-rc7-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:111 nmi_trigger_cpumask_backtrace+0x1b3/0x230 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:3878 [inline] rcu_sched_clock_irq.cold+0x57/0x759 kernel/rcu/tree.c:2597 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:1428 __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:kernel_text_address+0x0/0x60 kernel/extable.c:94 Code: cf 8e 72 f0 48 81 fb d6 06 e4 8e 73 e7 41 bc 01 00 00 00 5b 44 89 e0 41 5c c3 48 c7 c7 04 f2 90 8d e8 f4 7d 70 00 eb c3 66 90 <55> 48 89 fd 48 83 ec 08 e8 63 ff ff ff 41 89 c0 b8 01 00 00 00 45 RSP: 0018:ffffc900035befc0 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffffffff81d6c90a RCX: 0000000000000000 RDX: 1ffff920006b7e07 RSI: ffffc900035bf980 RDI: ffffffff81d6c90a RBP: ffffc900035bf038 R08: ffffffff8e18bd94 R09: 0000000000000001 R10: fffff520006b7e09 R11: 000000000008808a R12: ffffc900035bf0a8 R13: 0000000000000000 R14: ffff88801effc040 R15: ffff888086ef1898 __kernel_text_address+0x9/0x30 kernel/extable.c:78 unwind_get_return_address arch/x86/kernel/unwind_orc.c:318 [inline] unwind_get_return_address+0x51/0x90 arch/x86/kernel/unwind_orc.c:313 arch_stack_walk+0x93/0xe0 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x85/0xb0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:259 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc mm/slab.c:3323 [inline] kmem_cache_alloc+0x265/0x560 mm/slab.c:3507 kmem_cache_zalloc include/linux/slab.h:714 [inline] jbd2_alloc_handle include/linux/jbd2.h:1603 [inline] new_handle fs/jbd2/transaction.c:481 [inline] jbd2__journal_start+0x191/0x930 fs/jbd2/transaction.c:508 __ext4_journal_start_sb+0x227/0x4a0 fs/ext4/ext4_jbd2.c:105 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline] ext4_dirty_inode+0x9d/0x110 fs/ext4/inode.c:5916 __mark_inode_dirty+0x45b/0xfe0 fs/fs-writeback.c:2399 mark_inode_dirty include/linux/fs.h:2451 [inline] generic_write_end+0x31b/0x500 fs/buffer.c:2202 ext4_da_write_end+0x1c2/0x990 fs/ext4/inode.c:3059 generic_perform_write+0x2c6/0x510 mm/filemap.c:3765 ext4_buffered_write_iter+0x1ac/0x3b0 fs/ext4/file.c:269 ext4_file_write_iter+0x423/0x14e0 fs/ext4/file.c:681 call_write_iter include/linux/fs.h:2162 [inline] do_iter_readv_writev+0x472/0x750 fs/read_write.c:725 do_iter_write+0x188/0x710 fs/read_write.c:851 vfs_iter_write+0x70/0xa0 fs/read_write.c:892 iter_file_splice_write+0x6fa/0xc10 fs/splice.c:689 do_splice_from fs/splice.c:767 [inline] direct_splice_actor+0x110/0x180 fs/splice.c:936 splice_direct_to_actor+0x34b/0x8c0 fs/splice.c:891 do_splice_direct+0x1b3/0x280 fs/splice.c:979 do_sendfile+0xaf2/0x1250 fs/read_write.c:1245 __do_sys_sendfile64 fs/read_write.c:1310 [inline] __se_sys_sendfile64 fs/read_write.c:1296 [inline] __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1296 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: 0033:0x7f8af04d9e99 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:00007f8aeee4f168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f8af05ecf60 RCX: 00007f8af04d9e99 RDX: 0000000000000000 RSI: 000000000000000a RDI: 0000000000000005 RBP: 00007f8af0533ff1 R08: 0000000000000000 R09: 0000000000000000 R10: 00008400fffffffb R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdc3d3fd3f R14: 00007f8aeee4f300 R15: 0000000000022000 NMI backtrace for cpu 1 CPU: 1 PID: 14744 Comm: syz-executor.5 Not tainted 5.16.0-rc7-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:111 nmi_trigger_cpumask_backtrace+0x1b3/0x230 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:3878 [inline] rcu_sched_clock_irq.cold+0x5c/0x759 kernel/rcu/tree.c:2597 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:1428 __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:kernel_text_address+0x0/0x60 kernel/extable.c:94 Code: cf 8e 72 f0 48 81 fb d6 06 e4 8e 73 e7 41 bc 01 00 00 00 5b 44 89 e0 41 5c c3 48 c7 c7 04 f2 90 8d e8 f4 7d 70 00 eb c3 66 90 <55> 48 89 fd 48 83 ec 08 e8 63 ff ff ff 41 89 c0 b8 01 00 00 00 45 RSP: 0018:ffffc900035befc0 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffffffff81d6c90a RCX: 0000000000000000 RDX: 1ffff920006b7e07 RSI: ffffc900035bf980 RDI: ffffffff81d6c90a RBP: ffffc900035bf038 R08: ffffffff8e18bd94 R09: 0000000000000001 R10: fffff520006b7e09 R11: 000000000008808a R12: ffffc900035bf0a8 R13: 0000000000000000 R14: ffff88801effc040 R15: ffff888086ef1898 __kernel_text_address+0x9/0x30 kernel/extable.c:78 unwind_get_return_address arch/x86/kernel/unwind_orc.c:318 [inline] unwind_get_return_address+0x51/0x90 arch/x86/kernel/unwind_orc.c:313 arch_stack_walk+0x93/0xe0 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x85/0xb0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:259 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc mm/slab.c:3323 [inline] kmem_cache_alloc+0x265/0x560 mm/slab.c:3507 kmem_cache_zalloc include/linux/slab.h:714 [inline] jbd2_alloc_handle include/linux/jbd2.h:1603 [inline] new_handle fs/jbd2/transaction.c:481 [inline] jbd2__journal_start+0x191/0x930 fs/jbd2/transaction.c:508 __ext4_journal_start_sb+0x227/0x4a0 fs/ext4/ext4_jbd2.c:105 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline] ext4_dirty_inode+0x9d/0x110 fs/ext4/inode.c:5916 __mark_inode_dirty+0x45b/0xfe0 fs/fs-writeback.c:2399 mark_inode_dirty include/linux/fs.h:2451 [inline] generic_write_end+0x31b/0x500 fs/buffer.c:2202 ext4_da_write_end+0x1c2/0x990 fs/ext4/inode.c:3059 generic_perform_write+0x2c6/0x510 mm/filemap.c:3765 ext4_buffered_write_iter+0x1ac/0x3b0 fs/ext4/file.c:269 ext4_file_write_iter+0x423/0x14e0 fs/ext4/file.c:681 call_write_iter include/linux/fs.h:2162 [inline] do_iter_readv_writev+0x472/0x750 fs/read_write.c:725 do_iter_write+0x188/0x710 fs/read_write.c:851 vfs_iter_write+0x70/0xa0 fs/read_write.c:892 iter_file_splice_write+0x6fa/0xc10 fs/splice.c:689 do_splice_from fs/splice.c:767 [inline] direct_splice_actor+0x110/0x180 fs/splice.c:936 splice_direct_to_actor+0x34b/0x8c0 fs/splice.c:891 do_splice_direct+0x1b3/0x280 fs/splice.c:979 do_sendfile+0xaf2/0x1250 fs/read_write.c:1245 __do_sys_sendfile64 fs/read_write.c:1310 [inline] __se_sys_sendfile64 fs/read_write.c:1296 [inline] __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1296 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: 0033:0x7f8af04d9e99 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:00007f8aeee4f168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f8af05ecf60 RCX: 00007f8af04d9e99 RDX: 0000000000000000 RSI: 000000000000000a RDI: 0000000000000005 RBP: 00007f8af0533ff1 R08: 0000000000000000 R09: 0000000000000000 R10: 00008400fffffffb R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdc3d3fd3f R14: 00007f8aeee4f300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: cf iret 1: 8e 72 f0 mov -0x10(%rdx),%? 4: 48 81 fb d6 06 e4 8e cmp $0xffffffff8ee406d6,%rbx b: 73 e7 jae 0xfffffff4 d: 41 bc 01 00 00 00 mov $0x1,%r12d 13: 5b pop %rbx 14: 44 89 e0 mov %r12d,%eax 17: 41 5c pop %r12 19: c3 retq 1a: 48 c7 c7 04 f2 90 8d mov $0xffffffff8d90f204,%rdi 21: e8 f4 7d 70 00 callq 0x707e1a 26: eb c3 jmp 0xffffffeb 28: 66 90 xchg %ax,%ax * 2a: 55 push %rbp <-- trapping instruction 2b: 48 89 fd mov %rdi,%rbp 2e: 48 83 ec 08 sub $0x8,%rsp 32: e8 63 ff ff ff callq 0xffffff9a 37: 41 89 c0 mov %eax,%r8d 3a: b8 01 00 00 00 mov $0x1,%eax 3f: 45 rex.RB