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INFO: rcu detected stall in new_sync_write

Status: auto-closed as invalid on 2019/10/25 14:21
Subsystems: kernel
[Documentation on labels]
First crash: 1872d, last: 1739d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in new_sync_write (2) cgroups 1 1538d 1538d 0/26 auto-closed as invalid on 2020/04/06 23:25
upstream INFO: rcu detected stall in new_sync_write (3) kernel 1 1146d 1146d 0/26 auto-closed as invalid on 2021/06/03 04:29

Sample crash report:
rcu: INFO: rcu_sched detected stalls on CPUs/tasks:
	(detected by 1, t=10502 jiffies, g=452161, q=208)
rcu: All QSes seen, last rcu_sched kthread activity 10500 (4295245324-4295234824), jiffies_till_next_fqs=1, root ->qsmask 0x0
syz-executor.4  R  running task    25464 16331  24595 0x00004002
Call Trace:
 <IRQ>
 sched_show_task /kernel/sched/core.c:5755 [inline]
 sched_show_task.cold+0x2ef/0x350 /kernel/sched/core.c:5730
 print_other_cpu_stall /kernel/rcu/tree_stall.h:410 [inline]
 check_cpu_stall /kernel/rcu/tree_stall.h:536 [inline]
 rcu_pending /kernel/rcu/tree.c:2736 [inline]
 rcu_sched_clock_irq.cold+0x837/0x8c0 /kernel/rcu/tree.c:2183
 update_process_times+0x32/0x80 /kernel/time/timer.c:1639
 tick_sched_handle+0xa2/0x190 /kernel/time/tick-sched.c:167
 tick_sched_timer+0x47/0x130 /kernel/time/tick-sched.c:1296
 __run_hrtimer /kernel/time/hrtimer.c:1389 [inline]
 __hrtimer_run_queues+0x364/0xd90 /kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x2ea/0x730 /kernel/time/hrtimer.c:1509
 local_apic_timer_interrupt /arch/x86/kernel/apic/apic.c:1068 [inline]
 smp_apic_timer_interrupt+0x10b/0x550 /arch/x86/kernel/apic/apic.c:1093
 apic_timer_interrupt+0xf/0x20 /arch/x86/entry/entry_64.S:828
 </IRQ>
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50 /kernel/kcov.c:95
Code: 89 25 24 5b 19 09 41 bc f4 ff ff ff e8 2d 35 ea ff 48 c7 05 0e 5b 19 09 00 00 00 00 e9 77 e9 ff ff 90 90 90 90 90 90 90 90 90 <55> 48 89 e5 65 48 8b 04 25 c0 fd 01 00 65 8b 15 f4 a6 90 7e 81 e2
RSP: 0018:ffff88807f35f2c8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000002 RBX: 0000000000000000 RCX: ffffffff81942816
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: ffff88807f35f428 R08: ffff88803ecac3c0 R09: fffffbfff14a6d51
R10: fffffbfff14a6d50 R11: ffffffff8a536a87 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: ffff88807f35f5c8
 shrink_zones /mm/vmscan.c:2940 [inline]
 do_try_to_free_pages+0x3cb/0x11e0 /mm/vmscan.c:2998
 try_to_free_mem_cgroup_pages+0x314/0xa00 /mm/vmscan.c:3300
 try_charge+0x648/0x1430 /mm/memcontrol.c:2399
 mem_cgroup_try_charge+0x136/0x590 /mm/memcontrol.c:6089
 mem_cgroup_try_charge_delay+0x1f/0xa0 /mm/memcontrol.c:6104
 shmem_getpage_gfp+0x88e/0x2650 /mm/shmem.c:1856
 shmem_getpage /mm/shmem.c:139 [inline]
 shmem_write_begin+0x105/0x1e0 /mm/shmem.c:2467
 generic_perform_write+0x23b/0x540 /mm/filemap.c:3327
 __generic_file_write_iter+0x25e/0x630 /mm/filemap.c:3456
 generic_file_write_iter+0x356/0x620 /mm/filemap.c:3488
 call_write_iter /./include/linux/fs.h:1870 [inline]
 new_sync_write+0x4d3/0x770 /fs/read_write.c:483
 __vfs_write+0xe1/0x110 /fs/read_write.c:496
 vfs_write+0x268/0x5d0 /fs/read_write.c:558
 ksys_write+0x14f/0x290 /fs/read_write.c:611
 __do_sys_write /fs/read_write.c:623 [inline]
 __se_sys_write /fs/read_write.c:620 [inline]
 __x64_sys_write+0x73/0xb0 /fs/read_write.c:620
 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459819
Code: fd b7 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fe792de5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459819
RDX: 00000000ffffff76 RSI: 0000000020000000 RDI: 0000000000000005
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe792de66d4
R13: 00000000004c98c0 R14: 00000000004e0d38 R15: 00000000ffffffff
rcu: rcu_sched kthread starved for 10500 jiffies! g452161 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_sched       R  running task    29048    10      2 0x80004000
Call Trace:
 context_switch /kernel/sched/core.c:3254 [inline]
 __schedule+0x772/0x1530 /kernel/sched/core.c:3880
 schedule+0xa5/0x260 /kernel/sched/core.c:3944
 schedule_timeout+0x44e/0xbc0 /kernel/time/timer.c:1807
 rcu_gp_fqs_loop /kernel/rcu/tree.c:1611 [inline]
 rcu_gp_kthread+0x835/0x1320 /kernel/rcu/tree.c:1768
 kthread+0x361/0x430 /kernel/kthread.c:255
 ret_from_fork+0x24/0x30 /arch/x86/entry/entry_64.S:352

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/07/20 20:12 upstream c6dd78fcb8ee 1656845f .config console log report ci-upstream-kasan-gce-root
2019/03/23 09:35 upstream fd1f297b794c 3361bde5 .config console log report ci-upstream-kasan-gce-selinux-root
2019/03/15 05:37 upstream 3b319ee220a8 d72db19b .config console log report ci-upstream-kasan-gce-root
2019/03/12 10:57 upstream ea295481b6e3 12365b99 .config console log report ci-upstream-kasan-gce-root
2019/03/10 06:30 linux-next cf08baa29613 12365b99 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.