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INFO: rcu detected stall in proc_reg_read (5)

Status: auto-closed as invalid on 2020/11/18 23:09
Subsystems: fs
[Documentation on labels]
First crash: 1769d, last: 1769d
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in proc_reg_read mm 6 2378d 2457d 0/29 closed as dup on 2019/01/02 16:24
upstream INFO: rcu detected stall in proc_reg_read (2) kernel 36 2030d 2031d 0/29 closed as invalid on 2019/12/04 14:14
upstream INFO: rcu detected stall in proc_reg_read (6) fs 1 1512d 1512d 0/29 auto-closed as invalid on 2021/08/03 06:54
linux-4.19 INFO: rcu detected stall in proc_reg_read syz error 11 893d 1619d 0/1 upstream: reported syz repro on 2021/01/17 20:31
upstream INFO: rcu detected stall in proc_reg_read (4) kernel 9 1995d 1995d 0/29 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in proc_reg_read (3) kernel 3 1995d 1995d 0/29 closed as invalid on 2020/01/08 05:23

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=3de/1/0x4000000000000000 softirq=41464/41464 fqs=0 
	(detected by 1, t=10502 jiffies, g=69797, q=43)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 19717 Comm: syz-executor.1 Not tainted 5.9.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:770 [inline]
RIP: 0010:lock_acquire+0x27b/0xad0 kernel/locking/lockdep.c:5008
Code: 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 f8 06 00 00 48 83 3d ea c8 5b 08 00 0f 84 a6 05 00 00 48 8b 7c 24 08 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 03 44 24 10 48 c7
RSP: 0018:ffffc90000007bb0 EFLAGS: 00000082
RAX: 1ffffffff136c6c1 RBX: ffff8880959cc280 RCX: ffffffff815a14fb
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000082
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8c5f09e7
R10: fffffbfff18be13c R11: 0000000000000001 R12: 0000000000000000
R13: ffffffff8cc29d20 R14: 0000000000000000 R15: ffff8880959cc280
FS:  00007fafa50e7700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30525000 CR3: 0000000090248000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:159
 debug_object_activate+0x12e/0x3e0 lib/debugobjects.c:636
 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline]
 debug_activate kernel/time/hrtimer.c:480 [inline]
 enqueue_hrtimer+0x27/0x3f0 kernel/time/hrtimer.c:969
 __run_hrtimer kernel/time/hrtimer.c:1541 [inline]
 __hrtimer_run_queues+0xc1e/0xfc0 kernel/time/hrtimer.c:1588
 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1650
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0x142/0x5e0 arch/x86/kernel/apic/apic.c:1097
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [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:__sanitizer_cov_trace_pc+0x52/0x60 kernel/kcov.c:205
Code: 74 2b 8b 82 00 14 00 00 83 f8 02 75 20 48 8b 8a 08 14 00 00 8b 92 04 14 00 00 48 8b 01 48 83 c0 01 48 39 c2 76 07 48 89 34 c1 <48> 89 01 c3 66 2e 0f 1f 84 00 00 00 00 00 41 55 41 54 49 89 fc 55
RSP: 0018:ffffc90004b07078 EFLAGS: 00000216
RAX: 000000000000f4b2 RBX: ffffc90004b07105 RCX: ffffc90004889000
RDX: 0000000000040000 RSI: ffffffff83b40a4c RDI: 0000000000000001
RBP: ffff8880509e0d69 R08: 0000000000000002 R09: ffffc90004b07106
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000062
R13: 000000000000000c R14: dffffc0000000000 R15: ffffc90004b070f8
 string_nocheck lib/vsprintf.c:616 [inline]
 symbol_string+0x21c/0x370 lib/vsprintf.c:976
 pointer+0x185/0x970 lib/vsprintf.c:2223
 vsnprintf+0x5b2/0x14f0 lib/vsprintf.c:2621
 seq_vprintf fs/seq_file.c:379 [inline]
 seq_printf+0x195/0x240 fs/seq_file.c:394
 s_show+0xec/0x950 mm/vmalloc.c:3522
 seq_read+0xac4/0x1070 fs/seq_file.c:248
 pde_read fs/proc/inode.c:306 [inline]
 proc_reg_read+0x221/0x300 fs/proc/inode.c:318
 do_loop_readv_writev fs/read_write.c:734 [inline]
 do_loop_readv_writev fs/read_write.c:721 [inline]
 do_iter_read+0x48e/0x6e0 fs/read_write.c:955
 vfs_readv+0xe5/0x150 fs/read_write.c:1073
 kernel_readv fs/splice.c:355 [inline]
 default_file_splice_read.constprop.0+0x4e6/0x9e0 fs/splice.c:412
 do_splice_to+0x137/0x170 fs/splice.c:871
 splice_direct_to_actor+0x307/0x980 fs/splice.c:950
 do_splice_direct+0x1b3/0x280 fs/splice.c:1059
 do_sendfile+0x55f/0xd40 fs/read_write.c:1540
 __do_sys_sendfile64 fs/read_write.c:1601 [inline]
 __se_sys_sendfile64 fs/read_write.c:1587 [inline]
 __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1587
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45d4d9
Code: 5d 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 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fafa50e6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000027880 RCX: 000000000045d4d9
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000005
RBP: 000000000118cf88 R08: 0000000000000000 R09: 0000000000000000
R10: 000000010000004c R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007ffe739f107f R14: 00007fafa50e79c0 R15: 000000000118cf4c
rcu: rcu_preempt kthread starved for 10502 jiffies! g69797 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:29664 pid:   10 ppid:     2 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 schedule_timeout+0x148/0x250 kernel/time/timer.c:1879
 rcu_gp_fqs_loop kernel/rcu/tree.c:1888 [inline]
 rcu_gp_kthread+0xae5/0x1b50 kernel/rcu/tree.c:2058
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/08/20 23:02 upstream da2968ff879b 1d75fe45 .config console log report ci-upstream-kasan-gce-selinux-root
* Struck through repros no longer work on HEAD.