syzbot


INFO: rcu detected stall in anon_pipe_write

Status: auto-obsoleted due to no activity on 2026/05/28 09:05
Subsystems: mm
Labels: prio:normal
[Documentation on labels]
First crash: 119d, last: 119d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
e55225e1-c257-42f5-85b0-f09eb895bcd6 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ INFO: rcu detected stall in anon_pipe_write 2026/05/18 21:10 2026/05/18 21:10 2026/05/18 21:47 9f74d39908454b73546eaf1b8211b48b66e5c0fe

			
		
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: soft lockup in anon_pipe_write trace 1 1 421d 417d 0/29 auto-obsoleted due to no activity on 2025/07/30 15:13

Sample crash report:
bridge0: received packet on veth0_to_bridge with own address as source address (addr:8e:6b:71:bd:08:35, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7728/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=30813, q=1871 ncpus=1)
task:syz.0.388       state:R  running task     stack:27920 pid:7728  tgid:7724  ppid:5824   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0xfee/0x60e0 kernel/sched/core.c:6907
 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7234
 irqentry_exit+0x17b/0x670 kernel/entry/common.c:239
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0xe64/0x1ea0 arch/x86/kernel/unwind_orc.c:687
Code: 00 fc ff df 4c 89 ea 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e d3 0d 00 00 41 39 5d 00 0f 84 cd 06 00 00 bd 01 00 00 00 <e9> 3a f5 ff ff ba a8 00 00 00 4c 89 f6 4c 89 ef 48 89 4c 24 18 e8
RSP: 0018:ffffc90003517390 EFLAGS: 00000287
RAX: ffffc90003518001 RBX: ffffc90003517b88 RCX: ffffffff91869001
RDX: ffffc90003517b90 RSI: ffffc90003517b58 RDI: ffffc90003517410
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000016fd3 R12: ffffc90003517450
R13: ffffc90003517400 R14: ffffc90003517b88 R15: ffffc90003517434
 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 save_stack+0x162/0x1e0 mm/page_owner.c:165
 __set_page_owner+0x8c/0x540 mm/page_owner.c:341
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x153/0x170 mm/page_alloc.c:1889
 prep_new_page mm/page_alloc.c:1897 [inline]
 get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3962
 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5250
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2484
 alloc_frozen_pages_noprof mm/mempolicy.c:2555 [inline]
 alloc_pages_noprof+0x131/0x390 mm/mempolicy.c:2575
 anon_pipe_get_page fs/pipe.c:124 [inline]
 anon_pipe_write+0xabf/0x1d40 fs/pipe.c:515
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6ac/0x1070 fs/read_write.c:688
 ksys_write+0x1f8/0x250 fs/read_write.c:740
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcee7b9c799
RSP: 002b:00007fcee8afe028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fcee7e16090 RCX: 00007fcee7b9c799
RDX: 0000000080000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 00007fcee7c32bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcee7e16128 R14: 00007fcee7e16090 R15: 00007fff17981148
 </TASK>
net_ratelimit: 7572 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:8e:6b:71:bd:08:35, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:8e:6b:71:bd:08:35, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
net_ratelimit: 8428 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:8e:6b:71:bd:08:35, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:8e:6b:71:bd:08:35, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:8e:6b:71:bd:08:35, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/27 09:04 upstream 3f4a08e64442 a2f13f71 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in anon_pipe_write
* Struck through repros no longer work on HEAD.