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INFO: rcu detected stall in sys_mkdirat

Status: auto-obsoleted due to no activity on 2023/07/11 04:05
Subsystems: ext4 net
[Documentation on labels]
First crash: 1213d, last: 1097d
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in sys_mkdirat 1 2 507d 545d 0/3 auto-obsoleted due to no activity on 2025/03/02 02:09
linux-5.15 INFO: rcu detected stall in sys_mkdirat 1 1 887d 887d 0/3 auto-obsoleted due to no activity on 2024/02/15 18:20
upstream INFO: rcu detected stall in sys_mkdirat (2) mm 1 44 281d 482d 0/29 auto-obsoleted due to no activity on 2025/10/13 21:11
linux-5.15 INFO: rcu detected stall in sys_mkdirat (3) 1 5 2d00h 158d 0/3 upstream: reported on 2025/11/05 18:14
linux-5.15 INFO: rcu detected stall in sys_mkdirat (2) 1 1 409d 409d 0/3 auto-obsoleted due to no activity on 2025/06/08 06:38
android-5-15 BUG: soft lockup in sys_mkdirat 1 8 676d 728d 0/2 auto-obsoleted due to no activity on 2024/09/03 20:00

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2665 jiffies s: 53213 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: 5096 Comm: syz-executor.1 Not tainted 6.3.0-rc6-syzkaller-00030-g2c40519251d6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x31/0x70 kernel/kcov.c:207
Code: ad bc 81 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b 14 25 c0 b8 03 00 a9 00 01 ff 00 74 0e 85 c9 74 35 8b 82 74 15 00 00 <85> c0 74 2b 8b 82 50 15 00 00 83 f8 02 75 20 48 8b 8a 58 15 00 00
RSP: 0018:ffffc90000007cc0 EFLAGS: 00000206
RAX: 0000000000000000 RBX: ffff888165a57400 RCX: 0000000000000100
RDX: ffff8880452c6280 RSI: ffffffff84854972 RDI: 0000000000000014
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 00000000000000c8 R11: 0000000000000001 R12: ffff888165a57400
R13: 0000000000000014 R14: ffff888165a574f0 R15: 0000000000000001
FS:  000055555627f400(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31f25000 CR3: 0000000044f7e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __get_random_u32_below+0x12/0x90 drivers/char/random.c:546
 get_random_u32_below include/linux/random.h:63 [inline]
 mrp_join_timer_arm+0x20/0x70 net/802/mrp.c:595
 mrp_join_timer+0xf5/0x120 net/802/mrp.c:611
 call_timer_fn+0x1a0/0x580 kernel/time/timer.c:1700
 expire_timers+0x29b/0x4b0 kernel/time/timer.c:1751
 __run_timers kernel/time/timer.c:2022 [inline]
 __run_timers kernel/time/timer.c:1995 [inline]
 run_timer_softirq+0x326/0x910 kernel/time/timer.c:2035
 __do_softirq+0x1d4/0x905 kernel/softirq.c:571
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x114/0x190 kernel/softirq.c:650
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x97/0xc0 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:__orc_find+0xa8/0xf0 arch/x86/kernel/unwind_orc.c:60
Code: 75 48 48 63 03 48 01 d8 48 39 c1 73 b0 4c 8d 63 fc 49 39 ec 73 b3 4d 29 ee 49 c1 fe 02 4b 8d 04 76 48 8d 04 46 48 83 c4 10 5b <5d> 41 5c 41 5d 41 5e 41 5f c3 48 83 c4 10 31 c0 5b 5d 41 5c 41 5d
RSP: 0018:ffffc9000350f320 EFLAGS: 00000286
RAX: ffffffff8f0f01be RBX: 0000000000000001 RCX: ffffffff8222b4ba
RDX: 0000000000000000 RSI: ffffffff8f0f01be RDI: ffffffff8e91d594
RBP: ffffffff8e91d598 R08: ffffffff8f0f01be R09: ffffc9000350f3f4
R10: 0000000000000001 R11: 0000000000094001 R12: ffffffff8e91d594
R13: ffffffff8e91d594 R14: 0000000000000000 R15: dffffc0000000000
 orc_find arch/x86/kernel/unwind_orc.c:193 [inline]
 unwind_next_frame+0x2b3/0x1ef0 arch/x86/kernel/unwind_orc.c:467
 arch_stack_walk+0x81/0xf0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x90/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 __kasan_slab_alloc+0x7f/0x90 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:186 [inline]
 slab_post_alloc_hook mm/slab.h:769 [inline]
 slab_alloc_node mm/slab.c:3257 [inline]
 slab_alloc mm/slab.c:3266 [inline]
 __kmem_cache_alloc_lru mm/slab.c:3443 [inline]
 kmem_cache_alloc+0x1bd/0x3f0 mm/slab.c:3452
 ext4_es_alloc_extent fs/ext4/extents_status.c:456 [inline]
 __es_insert_extent+0x39b/0x13e0 fs/ext4/extents_status.c:794
 ext4_es_insert_extent+0x302/0xbb0 fs/ext4/extents_status.c:852
 ext4_map_blocks+0x974/0x18d0 fs/ext4/inode.c:720
 ext4_getblk+0x61f/0x850 fs/ext4/inode.c:863
 ext4_bread+0x2e/0x190 fs/ext4/inode.c:919
 ext4_append+0x23b/0x540 fs/ext4/namei.c:83
 ext4_init_new_dir+0x262/0x4c0 fs/ext4/namei.c:2955
 ext4_mkdir+0x3d3/0xb20 fs/ext4/namei.c:3001
 vfs_mkdir+0x242/0x460 fs/namei.c:4038
 do_mkdirat+0x28d/0x310 fs/namei.c:4061
 __do_sys_mkdirat fs/namei.c:4076 [inline]
 __se_sys_mkdirat fs/namei.c:4074 [inline]
 __x64_sys_mkdirat+0x119/0x170 fs/namei.c:4074
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f87cb68b187
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 02 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:00007ffca561ce78 EFLAGS: 00000206 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007ffca561cf00 RCX: 00007f87cb68b187
RDX: 00000000000001ff RSI: 00007ffca561cf00 RDI: 00000000ffffff9c
RBP: 00007ffca561cedc R08: 0000000000000000 R09: 0000000000000006
R10: 00007ffca561cc14 R11: 0000000000000206 R12: 0000555556280810
R13: 000055555628086b R14: 000000000000000c R15: 00007ffca561cf40
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/04/12 04:02 upstream 2c40519251d6 49faf98d .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in sys_mkdirat
2022/12/17 02:02 upstream 77856d911a8c 05494336 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in sys_mkdirat
2023/03/31 13:05 linux-next 4b0f4525dc4f f325deb0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in sys_mkdirat
* Struck through repros no longer work on HEAD.