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INFO: rcu detected stall in sys_symlinkat (2)

Status: auto-obsoleted due to no activity on 2023/06/03 10:14
Subsystems: ext4 lsm
[Documentation on labels]
First crash: 675d, last: 582d
Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_symlinkat (3) ext4 3 436d 489d 0/28 auto-obsoleted due to no activity on 2023/10/26 22:46
linux-5.15 INFO: rcu detected stall in sys_symlinkat 1 500d 500d 0/3 auto-obsoleted due to no activity on 2023/09/03 15:54
linux-5.15 INFO: rcu detected stall in sys_symlinkat (3) 2 112d 137d 0/3 auto-obsoleted due to no activity on 2024/09/25 17:37
linux-6.1 INFO: rcu detected stall in sys_symlinkat (2) 1 284d 284d 0/3 auto-obsoleted due to no activity on 2024/04/06 00:16
upstream INFO: rcu detected stall in sys_symlinkat kvm 5 769d 869d 0/28 auto-obsoleted due to no activity on 2022/11/28 07:06
linux-6.1 INFO: rcu detected stall in sys_symlinkat 1 529d 529d 0/3 auto-obsoleted due to no activity on 2023/08/23 09:07
upstream INFO: rcu detected stall in sys_symlinkat (4) ext4 1 313d 313d 0/28 auto-obsoleted due to no activity on 2024/02/27 04:07
linux-5.15 INFO: rcu detected stall in sys_symlinkat (2) 1 309d 309d 0/3 auto-obsoleted due to no activity on 2024/03/12 11:22
android-5-15 BUG: soft lockup in sys_symlinkat 13 84d 175d 0/2 premoderation: reported on 2024/04/15 06:45

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-...D } 2662 jiffies s: 90185 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 19083 Comm: syz-executor.5 Not tainted 6.2.0-syzkaller-13534-gb01fe98d34f3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
RIP: 0010:check_preemption_disabled+0x19/0x110 lib/smp_processor_id.c:14
Code: 78 58 8b eb 0c 66 2e 0f 1f 84 00 00 00 00 00 66 90 41 57 41 56 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 <65> 8b 1d 8c e2 4b 75 65 8b 05 81 e2 4b 75 a9 ff ff ff 7f 74 22 65
RSP: 0018:ffffc90000007c40 EFLAGS: 00000082
RAX: 5240d356cfa24300 RBX: 1ffff92000000f98 RCX: 0000000080010002
RDX: ffff8880262dd7c0 RSI: ffffffff8b0a9840 RDI: ffffffff8b587860
RBP: 00000000ffffffff R08: ffffffff817bf402 R09: fffffbfff1ce8d76
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000046
R13: ffff8880262dd7c0 R14: 00000000ffffffff R15: ffffffff8d127820
FS:  0000555556d97400(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4ebf90e265 CR3: 000000007daf7000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lockdep_recursion_inc kernel/locking/lockdep.c:462 [inline]
 lock_is_held_type+0x7a/0x190 kernel/locking/lockdep.c:5711
 lock_is_held include/linux/lockdep.h:283 [inline]
 rcu_read_lock_sched_held+0x8d/0x130 kernel/rcu/update.c:125
 trace_hrtimer_expire_exit include/trace/events/timer.h:282 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x76b/0x1030 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x396/0x980 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline]
 __sysvec_apic_timer_interrupt+0x19c/0x690 arch/x86/kernel/apic/apic.c:1113
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1107
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:rcu_lockdep_current_cpu_online+0xf1/0x120 kernel/rcu/tree.c:4084
Code: 6d 00 4c 23 3b 75 1a 48 c7 c7 00 d1 12 8d be 04 00 00 00 e8 41 90 6d 00 83 3d 4a 33 9d 0b 00 74 11 b0 01 65 ff 0d c7 16 8e 7e <74> 0a 5b 41 5e 41 5f c3 31 c0 eb ed e8 ce fb 8a ff eb ef 48 c7 c7
RSP: 0018:ffffc900151f7aa0 EFLAGS: 00000282
RAX: 1ffffffff1a25901 RBX: ffffffff8d12c870 RCX: 0000000080000001
RDX: 0000000000000010 RSI: ffffffff8b587840 RDI: ffff8880b983cda0
RBP: ffffc900151f7b50 R08: dffffc0000000000 R09: ffffc900151f7be0
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc900151f7c20
R13: ffffc900151f7be0 R14: dffffc0000000000 R15: 0000000000000001
 rcu_read_lock_held_common kernel/rcu/update.c:112 [inline]
 rcu_read_lock_sched_held+0x78/0x130 kernel/rcu/update.c:123
 trace_kfree include/trace/events/kmem.h:94 [inline]
 kfree+0x4f/0x210 mm/slab_common.c:1006
 ext4_fname_free_filename+0x89/0xb0 fs/ext4/crypto.c:70
 ext4_lookup_entry fs/ext4/namei.c:1754 [inline]
 ext4_lookup+0x185/0x750 fs/ext4/namei.c:1820
 __lookup_hash+0x117/0x240 fs/namei.c:1602
 filename_create+0x291/0x530 fs/namei.c:3809
 do_symlinkat+0xfa/0x610 fs/namei.c:4417
 __do_sys_symlinkat fs/namei.c:4440 [inline]
 __se_sys_symlinkat fs/namei.c:4437 [inline]
 __x64_sys_symlinkat+0x99/0xb0 fs/namei.c:4437
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f4ebf88ba37
Code: 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0a 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe8459c298 EFLAGS: 00000202 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f4ebf88ba37
RDX: 00007f4ebf8e7bab RSI: 00000000ffffff9c RDI: 00007ffe8459c360
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffe8459c130
R10: 00007ffe8459bfe7 R11: 0000000000000202 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffe8459c360
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/03/05 10:10 upstream b01fe98d34f3 f8902b57 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in sys_symlinkat
2022/12/01 20:10 upstream ef4d3ea40565 e080de16 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in sys_symlinkat
* Struck through repros no longer work on HEAD.