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INFO: rcu detected stall in pte_alloc_one

Status: auto-obsoleted due to no activity on 2026/01/14 00:39
Reported-by: syzbot+e72009bc44a840fdd0b9@syzkaller.appspotmail.com
First crash: 148d, last: 148d
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in pte_alloc_one (3) cgroups mm 1 1 214d 214d 0/29 auto-obsoleted due to no activity on 2025/09/30 16:05
upstream INFO: rcu detected stall in pte_alloc_one cgroups mm 1 1 851d 851d 0/29 auto-obsoleted due to no activity on 2024/02/01 17:38
upstream INFO: rcu detected stall in pte_alloc_one (2) mm 1 5 459d 613d 0/29 auto-obsoleted due to no activity on 2025/02/26 23:44

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7548/1:b..l P4722/1:b..l P7550/1:b..l
	(detected by 1, t=10503 jiffies, g=26517, q=128)
task:modprobe        state:R  running task     stack:27680 pid: 7550 ppid:  3027 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_acquire+0xe5/0x3f0 kernel/locking/lockdep.c:5596
Code: 44 89 f0 48 0f a3 05 b2 9c 0d 0c 73 0d e8 73 b6 07 00 84 c0 0f 84 17 02 00 00 48 c7 c0 44 c9 69 8d 48 c1 e8 03 42 0f b6 04 38 <84> c0 0f 85 06 02 00 00 83 3d 20 d0 0d 0c 00 0f 84 ef 00 00 00 65
RSP: 0000:ffffc9000313f5c0 EFLAGS: 00000a07
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ee24890334768200
RDX: 0000000000000000 RSI: ffffffff8a59a4a0 RDI: ffffffff8a59a460
RBP: ffffc9000313f6e0 R08: dffffc0000000000 R09: fffffbfff1ad32b6
R10: fffffbfff1ad32b6 R11: 1ffffffff1ad32b5 R12: ffffffff8c11c660
R13: 1ffff92000627ec4 R14: 0000000000000000 R15: dffffc0000000000
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 is_bpf_text_address+0x1d/0x270 kernel/bpf/core.c:725
 kernel_text_address kernel/extable.c:151 [inline]
 __kernel_text_address+0x9a/0x100 kernel/extable.c:105
 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
 arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x9c/0xd0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3225 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 kmem_cache_alloc+0x100/0x290 mm/slub.c:3238
 ptlock_alloc+0x1c/0x60 mm/memory.c:5556
 ptlock_init include/linux/mm.h:2241 [inline]
 pgtable_pte_page_ctor include/linux/mm.h:2268 [inline]
 __pte_alloc_one include/asm-generic/pgalloc.h:66 [inline]
 pte_alloc_one+0xc5/0x2f0 arch/x86/mm/pgtable.c:33
 __do_fault+0xda/0x330 mm/memory.c:3922
 do_read_fault mm/memory.c:4264 [inline]
 do_fault mm/memory.c:4392 [inline]
 handle_pte_fault mm/memory.c:4650 [inline]
 __handle_mm_fault mm/memory.c:4785 [inline]
 handle_mm_fault+0x2949/0x43c0 mm/memory.c:4883
 do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1357
 handle_page_fault arch/x86/mm/fault.c:1445 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1501
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0033:0x7fc899f108f3
RSP: 002b:00007ffd3c5fb350 EFLAGS: 00010206
RAX: 00007fc899f298f0 RBX: 0000000000000030 RCX: 00007ffd3c7bd000
RDX: 00007fc899f29608 RSI: 00007fc899f29c98 RDI: 00007fc899f29be8
RBP: 00007ffd3c5fb600 R08: 00007fc899f29ea8 R09: 0000000000000000
R10: 00000000c0000002 R11: fffffffffffff000 R12: 00007fc899f29280
R13: 0000000000000001 R14: 00007fc899f298f0 R15: 0000000000000001
 </TASK>
task:kworker/u4:9    state:R  running task     stack:21896 pid: 4722 ppid:     2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_acquire+0x1f2/0x3f0 kernel/locking/lockdep.c:5627
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f6 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc900038d7aa0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: f406b0d2d6734900
RDX: 0000000000000000 RSI: ffffffff8a0b2ac0 RDI: ffffffff8a59a4c0
RBP: ffffc900038d7bc0 R08: dffffc0000000000 R09: fffffbfff1ff7a19
R10: fffffbfff1ff7a19 R11: 1ffffffff1ff7a18 R12: ffffffff8c11c660
R13: 1ffff9200071af60 R14: 0000000000000246 R15: dffffc0000000000
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
 batadv_nc_worker+0xc9/0x5c0 net/batman-adv/network-coding.c:723
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
task:dhcpcd-run-hook state:R  running task     stack:27424 pid: 7548 ppid:  7538 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__lt_find include/linux/rbtree_latch.h:-1 [inline]
RIP: 0010:latch_tree_find include/linux/rbtree_latch.h:208 [inline]
RIP: 0010:bpf_ksym_find kernel/bpf/core.c:692 [inline]
RIP: 0010:is_bpf_text_address+0xc3/0x270 kernel/bpf/core.c:726
Code: 00 00 00 00 00 fc ff df 44 8b 2d 58 1e 5d 0a 45 89 ef 41 83 e7 01 4e 8d 34 fd b0 f3 e0 8b 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 <74> 08 4c 89 f7 e8 13 5d 38 00 4d 8b 36 4d 85 f6 0f 84 be 00 00 00
RSP: 0018:ffffc90002f5f460 EFLAGS: 00000246
RAX: 1ffffffff17c1e76 RBX: 00007f0eaa166c3a RCX: ffff88801fc98000
RDX: 0000000000000000 RSI: ffffffff8a59a4a0 RDI: ffffffff8a59a460
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff1ff7a19
R10: fffffbfff1ff7a19 R11: 1ffffffff1ff7a18 R12: dffffc0000000000
R13: 0000000000000172 R14: ffffffff8be0f3b0 R15: 0000000000000000
 kernel_text_address kernel/extable.c:151 [inline]
 __kernel_text_address+0x9a/0x100 kernel/extable.c:105
 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
 arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x9c/0xd0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3225 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 kmem_cache_alloc+0x100/0x290 mm/slub.c:3238
 kmem_cache_zalloc include/linux/slab.h:725 [inline]
 lsm_file_alloc security/security.c:574 [inline]
 security_file_alloc+0x30/0x110 security/security.c:1530
 __alloc_file+0xc2/0x240 fs/file_table.c:137
 alloc_empty_file+0x90/0x180 fs/file_table.c:181
 path_openat+0xfc/0x2f30 fs/namei.c:3728
 do_filp_open+0x1b3/0x3e0 fs/namei.c:3769
 do_sys_openat2+0x142/0x4a0 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1280
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0eaa166c3a
RSP: 002b:00007fff8ae69eb8 EFLAGS: 00000206 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0eaa166c3a
RDX: 0000000000090800 RSI: 000056536dcc3520 RDI: 00000000ffffff9c
RBP: 000056536dcc32fe R08: 00007f0eaa242ac0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 00007fff8ae6a018
R13: 000056536dcc32f8 R14: 0000000000000001 R15: 000056536dcc3547
 </TASK>
rcu: rcu_preempt kthread starved for 10611 jiffies! g26517 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27296 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:729

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/06 00:39 linux-5.15.y 29e53a5b1c4f 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in pte_alloc_one
* Struck through repros no longer work on HEAD.