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INFO: rcu detected stall in compat_sys_recvmmsg_time32 (2)

Status: auto-obsoleted due to no activity on 2026/05/13 13:21
Subsystems: mm
[Documentation on labels]
First crash: 122d, last: 122d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
eb940a2a-9ed7-41ac-9452-049b6a586fc4 repro INFO: rcu detected stall in compat_sys_recvmmsg_time32 (2) 2026/03/07 02:00 2026/03/07 02:00 2026/03/07 02:10 31e9c887f7dc24e04b3ca70d0d54fc34141844b0
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in compat_sys_recvmmsg_time32 mm block cgroups 1 2 233d 305d 0/29 auto-obsoleted due to no activity on 2026/01/22 13:09

Sample crash report:
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): P6745/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=16725, q=2662 ncpus=2)
task:syz.4.238       state:R  running task     stack:25536 pid:6745  tgid:6743  ppid:5838   task_flags:0x400040 flags:0x10080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1568/0x5290 kernel/sched/core.c:6907
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234
 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+0x221/0x330 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 41 96 fc 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 bb c3 75 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d e8 21 73
RSP: 0000:ffffc900050e6a38 EFLAGS: 00000282
RAX: 634f67362301a500 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 00000000b0f12c24 RSI: ffffffff8e14accf RDI: ffffffff8c276500
RBP: ffffffff8175b275 R08: ffffffff8175b275 R09: ffffffff8e75e0a0
R10: ffffc900050e6b98 R11: ffffffff81af97d0 R12: 0000000000000002
R13: ffffffff8e75e0a0 R14: 0000000000000000 R15: 0000000000000246
 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
 __set_page_owner+0x8d/0x4c0 mm/page_owner.c:341
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x228/0x280 mm/page_alloc.c:1884
 prep_new_page mm/page_alloc.c:1892 [inline]
 get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3950
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5245
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486
 folio_alloc_mpol_noprof mm/mempolicy.c:2505 [inline]
 vma_alloc_folio_noprof+0xea/0x210 mm/mempolicy.c:2540
 folio_prealloc mm/memory.c:-1 [inline]
 wp_page_copy mm/memory.c:3722 [inline]
 do_wp_page+0x127b/0x5990 mm/memory.c:4183
 handle_pte_fault mm/memory.c:6292 [inline]
 __handle_mm_fault mm/memory.c:6414 [inline]
 handle_mm_fault+0x1520/0x32a0 mm/memory.c:6583
 do_user_addr_fault+0x75b/0x1360 arch/x86/mm/fault.c:1385
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0010:__put_user_nocheck_4+0x3/0x10 arch/x86/lib/putuser.S:104
Code: d9 0f 01 cb 89 01 31 c9 0f 01 ca c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 01 cb <89> 01 31 c9 0f 01 ca e9 d1 75 03 00 90 90 90 90 90 90 90 90 90 90
RSP: 0000:ffffc900050e7858 EFLAGS: 00050282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00000000800dd018
RDX: ffff88802629dac0 RSI: 0000000080000002 RDI: 00000000ffffffff
RBP: ffffc900050e79d0 R08: ffffc900050e7627 R09: 1ffff92000a1cec4
R10: dffffc0000000000 R11: fffff52000a1cec5 R12: 1ffff92000a1cf18
R13: 0000000080000002 R14: 00000000800dd000 R15: dffffc0000000000
 ____sys_recvmsg+0x2be/0x4a0 net/socket.c:2825
 ___sys_recvmsg+0x215/0x590 net/socket.c:2854
 do_recvmmsg+0x3a5/0x800 net/socket.c:2941
 __sys_recvmmsg+0x1a5/0x290 net/socket.c:3023
 __do_compat_sys_recvmmsg_time32 net/compat.c:418 [inline]
 __se_compat_sys_recvmmsg_time32 net/compat.c:414 [inline]
 __ia32_compat_sys_recvmmsg_time32+0xbf/0xe0 net/compat.c:414
 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: 0023:0xf708ef6c
RSP: 002b:00000000f545c50c EFLAGS: 00000206 ORIG_RAX: 0000000000000151
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000800000c0
RDX: 0000000000010106 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
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:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:32:21:9d:2b:9c:b4, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:86:6d:96:90:8a:93, 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 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:86:6d:96:90:8a:93, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:32:21:9d:2b:9c:b4, 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:1b, vlan:0)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/12 13:17 upstream c22e26bd0906 76a109e2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in compat_sys_recvmmsg_time32
* Struck through repros no longer work on HEAD.