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INFO: rcu detected stall in compat_sys_ia32_clone (2)

Status: auto-obsoleted due to no activity on 2026/06/11 13:33
Subsystems: mm
Labels: prio:high
[Documentation on labels]
First crash: 325d, last: 100d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
ff973008-5599-4ac7-90d8-94e020e9f1aa assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ✅ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ INFO: rcu detected stall in compat_sys_ia32_clone (2) 2026/05/25 03:02 2026/05/25 03:02 2026/05/25 04:28 c69befb30ac10e158cc9d1557b508ee3f0eca1de

			
		
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in compat_sys_ia32_clone mm 1 3 615d 630d 0/29 auto-obsoleted due to no activity on 2025/01/11 22:30

Sample crash report:
bridge0: received packet on veth0_to_bridge with own address as source address (addr:be:29:ef:a9:36:31, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P18272/1:b..l
rcu: 	(detected by 0, t=10503 jiffies, g=117165, q=1748 ncpus=2)
task:syz.4.3257      state:R  running task     stack:26216 pid:18272 tgid:18268 ppid:16585  task_flags:0x400040 flags:0x08080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x15dd/0x52d0 kernel/sched/core.c:6908
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7235
 irqentry_exit+0x599/0x620 kernel/entry/common.c:239
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x20b/0x2e0 kernel/locking/lockdep.c:5872
Code: e9 30 ff ff ff e8 65 a8 0c 0a f7 c3 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 e1 75 7a 11 48 3b 44 24 30 75 33 fb 48 83 c4 38 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 46 8e 0f 0a cc 48 8d 3d 9e 5f 73
RSP: 0000:ffffc90003cfec98 EFLAGS: 00000282
RAX: bfdf9fbf9f375000 RBX: 0000000000000246 RCX: 0000000000000046
RDX: 000000005f7c8f42 RSI: ffffffff8e166f40 RDI: ffffffff8c27bc00
RBP: 0000000000000000 R08: ffffffff81767de5 R09: ffffffff8e75e420
R10: ffffc90003cfedf8 R11: ffffffff81b0c070 R12: 0000000000000002
R13: ffffffff8e75e420 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 rcu_read_lock include/linux/rcupdate.h:850 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
 unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 save_stack+0x122/0x230 mm/page_owner.c:165
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1433 [inline]
 __free_frozen_pages+0xc2b/0xdb0 mm/page_alloc.c:2978
 __slab_free+0x263/0x2b0 mm/slub.c:5576
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4542 [inline]
 slab_alloc_node mm/slub.c:4869 [inline]
 kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4876
 ptlock_alloc+0x20/0x70 mm/memory.c:7457
 ptlock_init include/linux/mm.h:3494 [inline]
 pagetable_pte_ctor include/linux/mm.h:3543 [inline]
 __pte_alloc_one_noprof include/asm-generic/pgalloc.h:79 [inline]
 pte_alloc_one+0x7a/0x370 arch/x86/mm/pgtable.c:18
 __pte_alloc+0x25/0x1a0 mm/memory.c:466
 copy_pte_range mm/memory.c:1250 [inline]
 copy_pmd_range+0x77d2/0x8050 mm/memory.c:1405
 copy_pud_range mm/memory.c:1442 [inline]
 copy_p4d_range mm/memory.c:1466 [inline]
 copy_page_range+0xbe8/0x11f0 mm/memory.c:1552
 dup_mmap+0xf40/0x1d90 mm/mmap.c:1841
 dup_mm kernel/fork.c:1530 [inline]
 copy_mm+0x13b/0x4b0 kernel/fork.c:1582
 copy_process+0x18b6/0x3cf0 kernel/fork.c:2223
 kernel_clone+0x248/0x8e0 kernel/fork.c:2654
 __do_compat_sys_ia32_clone arch/x86/kernel/sys_ia32.c:254 [inline]
 __se_compat_sys_ia32_clone arch/x86/kernel/sys_ia32.c:240 [inline]
 __ia32_compat_sys_ia32_clone+0x1b4/0x230 arch/x86/kernel/sys_ia32.c:240
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x20d/0x640 arch/x86/entry/syscall_32.c:307
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf707ef6c
RSP: 002b:00000000f542b4bc EFLAGS: 00000206 ORIG_RAX: 0000000000000078
RAX: ffffffffffffffda RBX: 0000000000100011 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00000000f542b5ec R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
net_ratelimit: 9522 callbacks suppressed
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 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:be:29:ef:a9:36:31, 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:be:29:ef:a9:36:31, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:be:29:ef:a9:36:31, vlan:0)
net_ratelimit: 11570 callbacks suppressed
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 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:be:29:ef:a9:36:31, 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:be:29:ef:a9:36:31, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:be:29:ef:a9:36:31, vlan:0)

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/13 13:27 upstream 0257f64bdac7 2f7f359d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in compat_sys_ia32_clone
2026/01/11 10:04 upstream 0fa27899e014 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in compat_sys_ia32_clone
2025/10/21 21:33 upstream 6548d364a3e8 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in compat_sys_ia32_clone
2025/09/10 13:11 upstream 9dd1835ecda5 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in compat_sys_ia32_clone
2025/08/26 14:01 upstream b6add54ba618 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in compat_sys_ia32_clone
2025/08/11 20:50 upstream 8f5ae30d69d7 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in compat_sys_ia32_clone
2025/07/31 03:38 upstream e8d780dcd957 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in compat_sys_ia32_clone
* Struck through repros no longer work on HEAD.