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INFO: rcu detected stall in sock_alloc_file (3)

Status: auto-obsoleted due to no activity on 2026/02/21 17:58
Subsystems: mm
[Documentation on labels]
First crash: 233d, last: 97d
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 INFO: rcu detected stall in sock_alloc_file (2) 1 1 86d 86d 0/2 upstream: reported on 2025/12/05 04:14
linux-6.6 INFO: rcu detected stall in sock_alloc_file 1 1 187d 187d 0/2 auto-obsoleted due to no activity on 2025/12/03 21:35
upstream INFO: rcu detected stall in sock_alloc_file fs 1 1 827d 827d 0/29 closed as invalid on 2024/02/01 10:31
linux-5.15 INFO: rcu detected stall in sock_alloc_file 1 1 238d 238d 0/3 auto-obsoleted due to no activity on 2025/10/13 16:41
upstream INFO: rcu detected stall in sock_alloc_file (2) mm 1 6 406d 458d 0/29 auto-obsoleted due to no activity on 2025/04/19 00:40
linux-5.15 INFO: rcu detected stall in sock_alloc_file (2) 1 4 1d12h 127d 0/3 upstream: reported on 2025/10/24 19:33
linux-6.1 INFO: rcu detected stall in sock_alloc_file 1 1 179d 179d 0/3 auto-obsoleted due to no activity on 2025/12/12 11:49

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P15594/1:b..l P5845/1:b..l P79/1:b..l P5494/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=96353, q=334 ncpus=2)
task:dhcpcd          state:R  running task     stack:21288 pid:5494  tgid:5494  ppid:5493   task_flags:0x400140 flags:0x00080001
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 1b cd d0 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90003a0f8c0 EFLAGS: 00000206
RAX: caa2ac80d2924200 RBX: 0000000000000000 RCX: caa2ac80d2924200
RDX: 0000000000000000 RSI: ffffffff8d8f2768 RDI: ffffffff8bbf0460
RBP: ffffffff822f137e R08: 0000000000000000 R09: ffffffff822f137e
R10: 0000000000000010 R11: ffffffff81ac2cb0 R12: 0000000000000002
R13: ffffffff8df3d2e0 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:867 [inline]
 __update_page_owner_free_handle+0x4b/0x470 mm/page_owner.c:271
 __reset_page_owner+0x85/0x1f0 mm/page_owner.c:309
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2906
 discard_slab mm/slub.c:3317 [inline]
 __put_partials+0x146/0x170 mm/slub.c:3864
 put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3939
 __slab_free+0x2b9/0x390 mm/slub.c:5913
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4962 [inline]
 slab_alloc_node mm/slub.c:5272 [inline]
 kmem_cache_alloc_lru_noprof+0x35d/0x6d0 mm/slub.c:5291
 __d_alloc+0x36/0x7a0 fs/dcache.c:1690
 d_alloc_pseudo+0x21/0xc0 fs/dcache.c:1821
 alloc_path_pseudo fs/file_table.c:363 [inline]
 alloc_file_pseudo+0xcc/0x210 fs/file_table.c:379
 sock_alloc_file+0xb8/0x2e0 net/socket.c:483
 __sys_socketpair+0x2db/0x560 net/socket.c:1834
 __do_sys_socketpair net/socket.c:1863 [inline]
 __se_sys_socketpair net/socket.c:1860 [inline]
 __x64_sys_socketpair+0x9b/0xb0 net/socket.c:1860
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0a4e0c973a
RSP: 002b:00007ffc7c223568 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 000055bee21c3040 RCX: 00007f0a4e0c973a
RDX: 0000000000000000 RSI: 0000000000080805 RDI: 0000000000000001
RBP: 00007ffc7c243990 R08: 0000000000000000 R09: 0000000000000001
R10: 00007ffc7c223580 R11: 0000000000000246 R12: 00007ffc7c223580
R13: 0000000000000001 R14: 0000000000000000 R15: 000055bec8472ac0
 </TASK>
task:kworker/u8:4    state:R  running task     stack:21128 pid:79    tgid:79    ppid:2      task_flags:0x24248060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 1b cd d0 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000218e5d8 EFLAGS: 00000206
RAX: c9b3c72a4faa5600 RBX: 0000000000000000 RCX: c9b3c72a4faa5600
RDX: 0000000000000000 RSI: ffffffff8d8f2768 RDI: ffffffff8bbf0460
RBP: ffffffff81738d25 R08: 0000000000000000 R09: ffffffff81738d25
R10: ffffc9000218e798 R11: ffffffff81ac2cb0 R12: 0000000000000002
R13: ffffffff8df3d2e0 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:867 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 save_stack+0xf5/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2906
 __slab_free+0x2e7/0x390 mm/slub.c:5954
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4962 [inline]
 slab_alloc_node mm/slub.c:5272 [inline]
 kmem_cache_alloc_noprof+0x367/0x6e0 mm/slub.c:5279
 ext4_init_io_end+0x29/0x130 fs/ext4/page-io.c:310
 ext4_do_writepages+0xb69/0x4610 fs/ext4/inode.c:2872
 ext4_writepages+0x205/0x350 fs/ext4/inode.c:3025
 do_writepages+0x32e/0x550 mm/page-writeback.c:2604
 __writeback_single_inode+0x145/0xff0 fs/fs-writeback.c:1719
 writeback_sb_inodes+0x6c7/0x1010 fs/fs-writeback.c:2015
 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2086
 wb_writeback+0x44f/0xaf0 fs/fs-writeback.c:2197
 wb_check_old_data_flush fs/fs-writeback.c:2301 [inline]
 wb_do_writeback fs/fs-writeback.c:2354 [inline]
 wb_workfn+0xaef/0xef0 fs/fs-writeback.c:2382
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
task:syz-executor    state:R  running task     stack:21736 pid:5845  tgid:5845  ppid:5824   task_flags:0x400140 flags:0x00080001
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 1b cd d0 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000413f658 EFLAGS: 00000206
RAX: 8adc58c1d6f9b100 RBX: 0000000000000000 RCX: 8adc58c1d6f9b100
RDX: 0000000000000000 RSI: ffffffff8d8f2768 RDI: ffffffff8bbf0460
RBP: ffffffff81738d25 R08: 0000000000000000 R09: ffffffff81738d25
R10: ffffc9000413f818 R11: ffffffff81ac2cb0 R12: 0000000000000002
R13: ffffffff8df3d2e0 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:867 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 save_stack+0xf5/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2906
 discard_slab mm/slub.c:3317 [inline]
 __put_partials+0x146/0x170 mm/slub.c:3864
 put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3939
 __slab_free+0x2b9/0x390 mm/slub.c:5913
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4962 [inline]
 slab_alloc_node mm/slub.c:5272 [inline]
 kmem_cache_alloc_noprof+0x367/0x6e0 mm/slub.c:5279
 alloc_empty_file+0x55/0x1d0 fs/file_table.c:237
 alloc_file fs/file_table.c:354 [inline]
 alloc_file_pseudo+0x13d/0x210 fs/file_table.c:383
 sock_alloc_file+0xb8/0x2e0 net/socket.c:483
 sock_map_fd net/socket.c:513 [inline]
 __sys_socket+0x13d/0x1b0 net/socket.c:1756
 __do_sys_socket net/socket.c:1761 [inline]
 __se_sys_socket net/socket.c:1759 [inline]
 __x64_sys_socket+0x7a/0x90 net/socket.c:1759
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f31dd590ee7
RSP: 002b:00007f31dd90f6c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 00007f31dd7b1300 RCX: 00007f31dd590ee7
RDX: 0000000000000006 RSI: 0000000000000001 RDI: 0000000000000002
RBP: 00007f31dd90fdec R08: 0000000000000000 R09: 00007f31dd90faf7
R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000001f1
R13: 00000000000927c0 R14: 0000000000000000 R15: 00007f31dd90fe40
 </TASK>
task:dhcpcd          state:R  running task     stack:24264 pid:15594 tgid:15594 ppid:5494   task_flags:0x400140 flags:0x00080001
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 1b cd d0 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9001a276f58 EFLAGS: 00000206
RAX: b99b4fa82563be00 RBX: 0000000000000000 RCX: b99b4fa82563be00
RDX: 0000000000000000 RSI: ffffffff8d8f2768 RDI: ffffffff8bbf0460
RBP: ffffffff81738d25 R08: 0000000000000000 R09: ffffffff81738d25
R10: ffffc9001a277128 R11: fffff5200344ee31 R12: 0000000000000002
R13: ffffffff8df3d2e0 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:867 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 __unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 save_stack+0xf5/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2906
 discard_slab mm/slub.c:3317 [inline]
 __put_partials+0x146/0x170 mm/slub.c:3864
 put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3939
 __slab_free+0x2b9/0x390 mm/slub.c:5913
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:408
 kasan_kmalloc include/linux/kasan.h:262 [inline]
 __do_kmalloc_node mm/slub.c:5634 [inline]
 __kmalloc_node_track_caller_noprof+0x568/0x800 mm/slub.c:5743
 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:601
 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:670
 alloc_skb include/linux/skbuff.h:1383 [inline]
 alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6671
 sock_alloc_send_pskb+0x84d/0x980 net/core/sock.c:2965
 unix_dgram_sendmsg+0x461/0x1850 net/unix/af_unix.c:2153
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:742
 sock_write_iter+0x279/0x360 net/socket.c:1195
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x5c9/0xb30 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0a4e04e407
RSP: 002b:00007ffc7c222aa0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f0a4dfc4740 RCX: 00007f0a4e04e407
RDX: 0000000000000035 RSI: 00007ffc7c222b00 RDI: 0000000000000005
RBP: 000055bec8479301 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffc7c222f30
R13: 0000000000000016 R14: 00007ffc7c223460 R15: 00007ffc7c223010
 </TASK>

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/23 07:16 upstream dd72c8fcf6d3 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in sock_alloc_file
2025/09/06 03:54 upstream e5d5d2331956 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in sock_alloc_file
2025/09/05 03:52 upstream 08b06c30a445 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in sock_alloc_file
2025/11/23 17:53 upstream d13f3ac64efb 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in sock_alloc_file
2025/07/10 20:28 upstream 8c2e52ebbe88 19d4829f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in sock_alloc_file
* Struck through repros no longer work on HEAD.