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INFO: rcu detected stall in inet_ioctl (3)

Status: auto-obsoleted due to no activity on 2026/06/05 17:53
Subsystems: mm
Labels: prio:low
[Documentation on labels]
First crash: 101d, last: 101d
✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision Error
8313c276-652a-429d-b75c-7bc171bfb0cc assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ INFO: rcu detected stall in inet_ioctl (3) 2026/05/31 22:47 2026/05/31 22:47 2026/05/31 23:25 6b4a844333e83556da95d61d7f207e7ef5cd4bc6

			
		
38137450-9753-49a5-bbbb-5bd345f77d93 assessment-security 💥 INFO: rcu detected stall in inet_ioctl (3) 2026/05/15 07:20 2026/05/15 07:20 2026/05/15 07:21 6ccb967e465e832a7bfd7a116ad00d52a0923a5d
failed to run ["git" "pull" "origin" "HEAD" "--depth=1" "--allow-unrelated-histories"]: exit status 128
From /app/workdir/repo/linux
 * branch                HEAD       -> FETCH_HEAD
Updating files:  ...
truncated to first 200 bytes; open job for full error
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in inet_ioctl 1 1 22d 22d 0/3 upstream: reported on 2026/05/26 00:31
upstream INFO: rcu detected stall in inet_ioctl net 1 1 2574d 2574d 0/29 auto-closed as invalid on 2019/10/25 09:21
upstream INFO: rcu detected stall in inet_ioctl (2) mm 1 1 628d 628d 0/29 auto-obsoleted due to no activity on 2024/12/25 20:16

Sample crash report:
bridge0: received packet on 1x9 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): P16940/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=240617, q=3180 ncpus=2)
task:syz.2.13059     state:R  running task     stack:27144 pid:16940 tgid:16937 ppid:15424  task_flags:0x400140 flags:0x00080002
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:__nr_to_section include/linux/mmzone.h:1976 [inline]
RIP: 0010:__pfn_to_section include/linux/mmzone.h:2114 [inline]
RIP: 0010:lookup_page_ext mm/page_ext.c:255 [inline]
RIP: 0010:page_ext_lookup+0x90/0x180 mm/page_ext.c:513
Code: 74 0c 48 c7 c7 40 72 2d 9a e8 5c d6 f3 ff 48 8b 05 85 6d f1 17 48 85 c0 74 36 4e 8d 34 f0 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 <74> 08 4c 89 f7 e8 36 d6 f3 ff 4d 8b 36 4d 85 f6 74 1b 48 c1 eb 0f
RSP: 0018:ffffc9000584f5a0 EFLAGS: 00000246
RAX: 1ffff11047ffc600 RBX: 000000000005ac10 RCX: ffff88802ef95b80
RDX: 0000000000000002 RSI: 0000000000001000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff823c0efa R09: ffffffff8e7602e0
R10: dffffc0000000000 R11: ffffed100ba962ae R12: 000000000005ac10
R13: dffffc0000000000 R14: ffff88823ffe3000 R15: 0000000000001000
 page_ext_iter_begin include/linux/page_ext.h:133 [inline]
 __page_table_check_zero+0x135/0x3e0 mm/page_table_check.c:139
 page_table_check_free include/linux/page_table_check.h:46 [inline]
 __free_pages_prepare mm/page_alloc.c:1434 [inline]
 __free_frozen_pages+0xc3b/0xdb0 mm/page_alloc.c:2978
 __slab_free+0x263/0x2b0 mm/slub.c:5551
 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:4515 [inline]
 slab_alloc_node mm/slub.c:4844 [inline]
 __kmalloc_cache_noprof+0x2ba/0x660 mm/slub.c:5353
 kmalloc_noprof include/linux/slab.h:950 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 call_usermodehelper_setup+0x8e/0x270 kernel/umh.c:362
 call_modprobe kernel/module/kmod.c:98 [inline]
 __request_module+0x3ba/0x660 kernel/module/kmod.c:173
 devinet_ioctl+0x138/0x1b30 net/ipv4/devinet.c:1083
 inet_ioctl+0x42a/0x560 net/ipv4/af_inet.c:1009
 sock_do_ioctl+0x101/0x320 net/socket.c:1254
 sock_ioctl+0x5c6/0x7f0 net/socket.c:1375
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb955d9c799
RSP: 002b:00007fb956cf3028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fb956016090 RCX: 00007fb955d9c799
RDX: 0000200000002280 RSI: 0000000000008914 RDI: 0000000000000009
RBP: 00007fb955e32bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb956016128 R14: 00007fb956016090 R15: 00007ffc0d2afc78
 </TASK>
net_ratelimit: 15989 callbacks suppressed
bridge0: received packet on 1x9 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 1x9 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on 1x9 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on 1x9 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
net_ratelimit: 16882 callbacks suppressed
bridge0: received packet on 1x9 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 1x9 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on 1x9 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on 1x9 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/07 17:42 net c113d5e32678 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in inet_ioctl
* Struck through repros no longer work on HEAD.