rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=753/1/0x4000000000000000 softirq=11591/11592 fqs=0 (t=10501 jiffies g=13601 q=43) rcu: rcu_preempt kthread starved for 10502 jiffies! g13601 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:28944 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xa9a/0x4940 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4778 Comm: syz-executor.0 Not tainted 5.16.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:native_apic_mem_write+0x8/0x10 arch/x86/include/asm/apic.h:110 Code: c7 c0 78 16 8f e8 18 11 8a 00 eb b0 66 0f 1f 44 00 00 be 01 00 00 00 e9 e6 45 2d 00 cc cc cc cc cc cc 89 ff 89 b7 00 c0 5f ff 0f 1f 80 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 53 89 fb 48 RSP: 0018:ffffc90000fd8eb8 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffffffff8b55ba80 RCX: 0000000000000020 RDX: 1ffffffff16ab752 RSI: 0000000000000114 RDI: 0000000000000380 RBP: ffff8880b9d27300 R08: 000000000000003f R09: 0000000000000000 R10: ffffffff816968f7 R11: 0000000000000000 R12: 0000000000000114 R13: 0000000000000020 R14: 0000000000000000 R15: ffff8880b9d2a400 FS: 00007f76ad3c5700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d83a000 CR3: 0000000075db2000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: apic_write arch/x86/include/asm/apic.h:394 [inline] lapic_next_event+0x4d/0x80 arch/x86/kernel/apic/apic.c:469 clockevents_program_event+0x254/0x370 kernel/time/clockevents.c:334 tick_program_event+0xac/0x140 kernel/time/tick-oneshot.c:44 hrtimer_interrupt+0x36e/0x790 kernel/time/hrtimer.c:1824 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:__sanitizer_cov_trace_pc+0x4c/0x60 kernel/kcov.c:205 Code: 0e 85 c9 74 35 8b 82 a4 15 00 00 85 c0 74 2b 8b 82 80 15 00 00 83 f8 02 75 20 48 8b 8a 88 15 00 00 8b 92 84 15 00 00 48 8b 01 <48> 83 c0 01 48 39 c2 76 07 48 89 34 c1 48 89 01 c3 0f 1f 00 41 55 RSP: 0018:ffffc90002e67330 EFLAGS: 00000246 RAX: 000000000003ffff RBX: 0000000000000000 RCX: ffffc90002eda000 RDX: 0000000000040000 RSI: ffffffff81a58e9b RDI: ffffea00015db4c0 RBP: ffffea00015db4c0 R08: 0000000000000000 R09: ffffea00015db4c7 R10: ffffffff81a58f53 R11: 0000000000000000 R12: ffffea00015db4c0 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 folio_flags.constprop.0+0xb/0x70 include/linux/page-flags.h:261 folio_test_swapbacked include/linux/page-flags.h:446 [inline] folio_test_swapcache include/linux/page-flags.h:487 [inline] folio_mapping+0x69/0x220 mm/util.c:719 mark_buffer_dirty+0x482/0x650 fs/buffer.c:1106 ext4_block_write_begin+0xb3e/0x1140 fs/ext4/inode.c:1085 ext4_da_write_begin+0x3eb/0xad0 fs/ext4/inode.c:2966 generic_perform_write+0x205/0x510 mm/filemap.c:3754 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: 0033:0x7f76aea4fe99 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:00007f76ad3c5168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f76aeb62f60 RCX: 00007f76aea4fe99 RDX: 0000000000000000 RSI: 000000000000000c RDI: 0000000000000005 RBP: 00007f76aeaa9ff1 R08: 0000000000000000 R09: 0000000000000000 R10: 00008400fffffffa R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd0aab2caf R14: 00007f76ad3c5300 R15: 0000000000022000 NMI backtrace for cpu 0 CPU: 0 PID: 4782 Comm: syz-executor.1 Not tainted 5.16.0-rc6-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+0x9d/0x746 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:unwind_next_frame+0x83a/0x1ce0 arch/x86/kernel/unwind_orc.c:466 Code: 12 00 00 41 80 7e 34 00 0f 85 00 fc ff ff 80 3d 96 a4 48 0c 00 0f 85 f3 fb ff ff e9 aa a0 cd 07 48 b8 00 00 00 00 00 fc ff df <48> 8b 54 24 08 48 c1 ea 03 80 3c 02 00 0f 85 2a 0f 00 00 4c 89 c0 RSP: 0018:ffffc90002e96e08 EFLAGS: 00000297 RAX: dffffc0000000000 RBX: 1ffff920005d2dc9 RCX: ffffffff8e153c75 RDX: 0000000000000005 RSI: 0000000000000001 RDI: 0000000000000001 RBP: 0000000000000001 R08: ffffffff8e153c70 R09: 0000000000000001 R10: fffff520005d2de7 R11: 000000000008808a R12: ffffc90002e96f28 R13: ffffc90002e96f15 R14: ffffc90002e96ee0 R15: ffffffff8e153c74 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:122 save_stack+0x151/0x1e0 mm/page_owner.c:119 __set_page_owner+0x45/0x2d0 mm/page_owner.c:181 prep_new_page mm/page_alloc.c:2418 [inline] get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4149 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5369 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2190 folio_alloc+0x1c/0x70 mm/mempolicy.c:2200 filemap_alloc_folio+0x8e/0xb0 mm/filemap.c:1036 __page_cache_alloc include/linux/pagemap.h:373 [inline] page_cache_ra_unbounded+0x36a/0x940 mm/readahead.c:215 do_page_cache_ra mm/readahead.c:268 [inline] ondemand_readahead+0x594/0x1090 mm/readahead.c:551 page_cache_async_ra mm/readahead.c:608 [inline] page_cache_async_ra+0x2e1/0x3f0 mm/readahead.c:583 page_cache_async_readahead include/linux/pagemap.h:1051 [inline] filemap_readahead mm/filemap.c:2531 [inline] filemap_get_pages+0x6f1/0x1be0 mm/filemap.c:2572 filemap_read+0x315/0xeb0 mm/filemap.c:2642 generic_file_read_iter+0x3b6/0x5a0 mm/filemap.c:2792 ext4_file_read_iter+0x1d4/0x5d0 fs/ext4/file.c:130 call_read_iter include/linux/fs.h:2156 [inline] generic_file_splice_read+0x453/0x6d0 fs/splice.c:311 do_splice_to+0x1bf/0x250 fs/splice.c:796 splice_direct_to_actor+0x2c2/0x8c0 fs/splice.c:870 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: 0033:0x7f47a7e03e99 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:00007f47a6779168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f47a7f16f60 RCX: 00007f47a7e03e99 RDX: 0000000000000000 RSI: 000000000000000c RDI: 0000000000000005 RBP: 00007f47a7e5dff1 R08: 0000000000000000 R09: 0000000000000000 R10: 00008400fffffffa R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd48109c9f R14: 00007f47a6779300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: c7 c0 78 16 8f e8 mov $0xe88f1678,%eax 6: 18 11 sbb %dl,(%rcx) 8: 8a 00 mov (%rax),%al a: eb b0 jmp 0xffffffbc c: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) 12: be 01 00 00 00 mov $0x1,%esi 17: e9 e6 45 2d 00 jmpq 0x2d4602 1c: cc int3 1d: cc int3 1e: cc int3 1f: cc int3 20: cc int3 21: cc int3 22: 89 ff mov %edi,%edi 24: 89 b7 00 c0 5f ff mov %esi,-0xa04000(%rdi) * 2a: c3 retq <-- trapping instruction 2b: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 32: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 39: fc ff df 3c: 53 push %rbx 3d: 89 fb mov %edi,%ebx 3f: 48 rex.W