syzbot


INFO: rcu detected stall in ext4_file_write_iter (2)

Status: auto-closed as invalid on 2021/01/10 12:58
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 848d, last: 848d
similar bugs (7):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in ext4_file_write_iter (3) 5 547d 637d 0/24 auto-closed as invalid on 2021/11/07 19:52
upstream INFO: rcu detected stall in ext4_file_write_iter (5) 3 288d 288d 0/24 auto-closed as invalid on 2022/06/25 07:58
upstream INFO: rcu detected stall in ext4_file_write_iter (4) C unreliable 58 383d 412d 0/24 closed as invalid on 2022/02/08 10:32
android-49 INFO: rcu detected stall in ext4_file_write_iter syz 2 1345d 1387d 0/3 public: reported syz repro on 2019/04/23 08:58
linux-4.14 INFO: rcu detected stall in ext4_file_write_iter C 7 19d 1397d 0/1 upstream: reported C repro on 2019/04/12 16:30
upstream INFO: rcu detected stall in ext4_file_write_iter C inconclusive done 93 910d 1443d 17/24 fixed on 2020/09/25 01:17
linux-4.19 INFO: rcu detected stall in ext4_file_write_iter C error 9 48d 1389d 0/1 upstream: reported C repro on 2019/04/20 13:09

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1):
------------[ cut here ]------------
WARNING: CPU: 1 PID: 30231 at kernel/sched/core.c:3013 rq_unlock kernel/sched/sched.h:1326 [inline]
WARNING: CPU: 1 PID: 30231 at kernel/sched/core.c:3013 try_invoke_on_locked_down_task+0x21d/0x2f0 kernel/sched/core.c:3019
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 30231 Comm: syz-executor.5 Not tainted 5.9.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x198/0x1fd lib/dump_stack.c:118
 panic+0x382/0x7fb kernel/panic.c:231
 __warn.cold+0x20/0x4b kernel/panic.c:600
 report_bug+0x1bd/0x210 lib/bug.c:198
 handle_bug+0x38/0x90 arch/x86/kernel/traps.c:234
 exc_invalid_op+0x14/0x40 arch/x86/kernel/traps.c:254
 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536
RIP: 0010:try_invoke_on_locked_down_task+0x21d/0x2f0 kernel/sched/core.c:3013
Code: 45 31 f6 49 39 c0 74 3a 8b 74 24 38 49 8d 78 18 4c 89 04 24 e8 a4 e7 08 00 4c 8b 04 24 4c 89 c7 e8 b8 09 d7 06 e9 20 ff ff ff <0f> 0b e9 7d fe ff ff 4c 89 ee 48 89 ef 41 ff d4 41 89 c6 e9 08 ff
RSP: 0018:ffffc90000da8be0 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 1ffff920001b517e RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8162da90 RDI: ffff8880943ba180
RBP: ffff8880943ba180 R08: 0000000000000033 R09: ffffffff8a05ad83
R10: 000000000000121b R11: 0000000000000001 R12: ffffffff8162da90
R13: ffffc90000da8d08 R14: ffff8880943ba180 R15: 0000000000000000
 rcu_print_task_stall kernel/rcu/tree_stall.h:267 [inline]
 print_other_cpu_stall kernel/rcu/tree_stall.h:475 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:634 [inline]
 rcu_pending kernel/rcu/tree.c:3639 [inline]
 rcu_sched_clock_irq.cold+0x97e/0xdfd kernel/rcu/tree.c:2521
 update_process_times+0x25/0xa0 kernel/time/timer.c:1710
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176
 tick_sched_timer+0x1d1/0x2a0 kernel/time/tick-sched.c:1328
 __run_hrtimer kernel/time/hrtimer.c:1524 [inline]
 __hrtimer_run_queues+0x1d5/0xfc0 kernel/time/hrtimer.c:1588
 hrtimer_interrupt+0x334/0x940 kernel/time/hrtimer.c:1650
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0x147/0x5f0 arch/x86/kernel/apic/apic.c:1097
 asm_call_irq_on_stack+0xf/0x20
 </IRQ>
 __run_sysvec_on_irqstack arch/x86/include/asm/irq_stack.h:37 [inline]
 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:89 [inline]
 sysvec_apic_timer_interrupt+0xb2/0xf0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x4b/0x80 kernel/locking/spinlock.c:199
Code: c0 78 6b fc 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 31 48 83 3d b6 22 d3 01 00 74 25 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 db ac 27 f9 65 8b 05 a4 b5 d8 77 85 c0 74 02 5d
RSP: 0018:ffffc9000af4f3a8 EFLAGS: 00000282
RAX: 1ffffffff13f8d6f RBX: dffffc0000000000 RCX: ffffffff815b7f72
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff8880594618b0 R08: 0000000000000001 R09: ffffffff8d0c3a6f
R10: fffffbfff1a1874d R11: 0000000000000000 R12: 0000000000000002
R13: 1ffff1100b28c31e R14: ffff8880898ca400 R15: ffff8880898ca400
 rwsem_down_write_slowpath+0x5bd/0xc60 kernel/locking/rwsem.c:1216
 __down_write kernel/locking/rwsem.c:1389 [inline]
 down_write+0x137/0x150 kernel/locking/rwsem.c:1532
 inode_lock include/linux/fs.h:779 [inline]
 ext4_dio_write_iter fs/ext4/file.c:492 [inline]
 ext4_file_write_iter+0xc1e/0x13f0 fs/ext4/file.c:658
 call_write_iter include/linux/fs.h:1882 [inline]
 do_iter_readv_writev+0x532/0x7b0 fs/read_write.c:721
 do_iter_write+0x188/0x670 fs/read_write.c:1026
 vfs_iter_write+0x70/0xa0 fs/read_write.c:1067
 iter_file_splice_write+0x721/0xbe0 fs/splice.c:770
 do_splice_from fs/splice.c:866 [inline]
 direct_splice_actor+0x171/0x2f0 fs/splice.c:1036
 splice_direct_to_actor+0x38c/0x980 fs/splice.c:991
 do_splice_direct+0x1b3/0x280 fs/splice.c:1079
 do_sendfile+0x55f/0xd40 fs/read_write.c:1548
 __do_sys_sendfile64 fs/read_write.c:1609 [inline]
 __se_sys_sendfile64 fs/read_write.c:1595 [inline]
 __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1595
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45de59
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f6c60d91c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000027ec0 RCX: 000000000045de59
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000004
RBP: 000000000118c010 R08: 0000000000000000 R09: 0000000000000000
R10: 00008400fffffffb R11: 0000000000000246 R12: 000000000118bfd4
R13: 00007ffff8c0a3ef R14: 00007f6c60d929c0 R15: 000000000118bfd4
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci-upstream-kasan-gce-root 2020/10/12 12:54 upstream bbf5c979011a 4a77ae0b .config console log report info
* Struck through repros no longer work on HEAD.