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INFO: rcu detected stall in sys_mkdirat (2)

Status: auto-obsoleted due to no activity on 2025/06/08 06:38
Reported-by: syzbot+ddd8c77b9da6d4f7459f@syzkaller.appspotmail.com
First crash: 463d, last: 463d
▶ ▼ Similar bugs (7)
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 561d 599d 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 941d 941d 0/3 auto-obsoleted due to no activity on 2024/02/15 18:20
upstream INFO: rcu detected stall in sys_mkdirat ext4 net 1 3 1151d 1267d 0/29 auto-obsoleted due to no activity on 2023/07/11 04:05
upstream INFO: rcu detected stall in sys_mkdirat (2) mm 1 44 335d 536d 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 7 22d 212d 0/3 upstream: reported on 2025/11/05 18:14
linux-6.1 INFO: rcu detected stall in sys_mkdirat (2) 1 4 1d23h 35d 0/3 upstream: reported on 2026/05/01 18:50
android-5-15 BUG: soft lockup in sys_mkdirat 1 8 730d 782d 0/2 auto-obsoleted due to no activity on 2024/09/03 20:00

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-....: (1 GPs behind) idle=a97/1/0x4000000000000000 softirq=7008/7009 fqs=5196 
	(detected by 0, t=10502 jiffies, g=7281, q=828)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4286 Comm: syz.2.7 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:__lock_acquire+0x1551/0x1ff0 kernel/locking/lockdep.c:5039
Code: b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 0f 85 d7 09 00 00 83 3d 85 d2 a7 0c 00 74 62 31 f6 89 f0 48 81 c4 88 00 00 00 5b <41> 5c 41 5d 41 5e 41 5f 5d c3 e8 50 c2 ad 02 85 c0 74 e1 48 c7 c0
RSP: 0018:ffffc90000dd05d0 EFLAGS: 00000082
RAX: 0000000000000001 RBX: ffffc90000dd0680 RCX: 1ffff920001ba070
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff888027583b80
RBP: 317fc64f4fe2bad8 R08: dffffc0000000000 R09: fffffbfff2131821
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000007
R13: ffff888027584668 R14: ffff888027583b80 R15: ffff8880275847a8
FS:  00007f1962ecf6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0c0a5d4d58 CR3: 0000000060755000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 BPF_PROG_RUN_ARRAY include/linux/bpf.h:1333 [inline]
 trace_call_bpf+0x146/0x660 kernel/trace/bpf_trace.c:127
 perf_trace_run_bpf_submit+0x7b/0x1d0 kernel/events/core.c:9991
 perf_trace_preemptirq_template+0x31d/0x430 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0x10e/0x190 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x84/0x520 kernel/rcu/tree_plugin.h:671
Code: f1 f1 f1 00 f2 f2 f2 49 89 04 17 66 41 c7 44 17 09 f3 f3 41 c6 44 17 0b f3 65 44 8b 25 4d 82 96 7e 41 f7 c4 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 3a 00 00 00 00 66 42 c7 44 3a
RSP: 0018:ffffc90000dd0b00 EFLAGS: 00000206
RAX: d3f4774b18db1200 RBX: 1ffff920001ba168 RCX: ffffffff81633dd8
RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: ffffffff8af9f2c0
RBP: ffffc90000dd0bd8 R08: dffffc0000000000 R09: fffffbfff2131822
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff8cb23d00
R13: ffff888027583fd8 R14: ffffc90000dd0b40 R15: 1ffff920001ba164
 __rcu_read_unlock+0x92/0x100 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:771 [inline]
 ieee80211_rx_napi+0x1f2/0x380 net/mac80211/rx.c:5006
 ieee80211_rx include/net/mac80211.h:4571 [inline]
 ieee80211_handle_queued_frames+0x103/0x1b0 net/mac80211/main.c:237
 tasklet_action_common+0x3cb/0x4a0
 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558
 __do_softirq kernel/softirq.c:592 [inline]
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:preempt_schedule_irq+0xf2/0x1c0 kernel/sched/core.c:6777
Code: 89 f5 49 c1 ed 03 eb 0d 48 f7 03 08 00 00 00 0f 84 97 00 00 00 bf 01 00 00 00 e8 f9 d4 0f f7 e8 b4 4d 3f f7 fb bf 01 00 00 00 <e8> a9 b3 ff ff 43 80 7c 3d 00 00 74 08 4c 89 f7 e8 19 b8 82 f7 48
RSP: 0018:ffffc9000329f480 EFLAGS: 00000282
RAX: d3f4774b18db1200 RBX: 1ffff92000653e98 RCX: ffffffff81633dd8
RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: 0000000000000001
RBP: ffffc9000329f530 R08: dffffc0000000000 R09: fffffbfff2131822
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000653e90
R13: 1ffff92000653e94 R14: ffffc9000329f4a0 R15: dffffc0000000000
 irqentry_exit+0x53/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:205
Code: 00 00 00 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 18 04 8a 0c 48 89 de 5b e9 47 11 49 00 cc cc cc cc cc cc cc 48 8b 04 24 <65> 48 8b 0d 24 ea 81 7e 65 8b 15 25 ea 81 7e 81 e2 00 01 ff 00 74
RSP: 0018:ffffc9000329f5f8 EFLAGS: 00000293
RAX: ffffffff8139ad45 RBX: ffff8880f4ae28c0 RCX: dffffc0000000000
RDX: ffff888027583b80 RSI: 000000000000002e RDI: 0000000000000040
RBP: ffff888023fee000 R08: ffffffff8139ad36 R09: 0000000080240010
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffea0000000000
R13: ffff888074ae28c0 R14: 0000000074ae28c0 R15: 000000000000002e
 phys_addr_valid arch/x86/mm/physaddr.h:7 [inline]
 __phys_addr+0x95/0x170 arch/x86/mm/physaddr.c:28
 virt_to_head_page include/linux/mm.h:900 [inline]
 ___cache_free+0x36/0x100 mm/slub.c:3506
 qlist_free_all+0x36/0x90 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x162/0x180 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 __kmalloc_node+0x151/0x390 mm/slub.c:4451
 kmalloc_node include/linux/slab.h:614 [inline]
 kvmalloc_node+0x80/0x140 mm/util.c:619
 kvmalloc include/linux/mm.h:805 [inline]
 memcg_update_list_lru_node mm/list_lru.c:392 [inline]
 memcg_update_list_lru mm/list_lru.c:473 [inline]
 memcg_update_all_list_lrus+0x276/0xbf0 mm/list_lru.c:510
 memcg_alloc_cache_id mm/memcontrol.c:2961 [inline]
 memcg_online_kmem mm/memcontrol.c:3653 [inline]
 mem_cgroup_css_alloc+0xb35/0x1540 mm/memcontrol.c:5307
 css_create kernel/cgroup/cgroup.c:5369 [inline]
 cgroup_apply_control_enable+0x398/0xae0 kernel/cgroup/cgroup.c:3189
 cgroup_mkdir+0xe72/0x10f0 kernel/cgroup/cgroup.c:5589
 kernfs_iop_mkdir+0x275/0x400 fs/kernfs/dir.c:1175
 vfs_mkdir+0x3b6/0x590 fs/namei.c:4065
 do_mkdirat+0x260/0x520 fs/namei.c:4090
 __do_sys_mkdirat fs/namei.c:4105 [inline]
 __se_sys_mkdirat fs/namei.c:4103 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4103
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f1965087169
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1962ecf038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f19652a0080 RCX: 00007f1965087169
RDX: 00000000000001ff RSI: 0000400000000000 RDI: ffffffffffffff9c
RBP: 00007f19651082a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f19652a0080 R15: 00007ffdb97656e8
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/02/28 06:37 linux-5.15.y c16c81c81336 6a8fcbc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_mkdirat
* Struck through repros no longer work on HEAD.