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INFO: rcu detected stall in kvm_vm_ioctl (3)

Status: auto-obsoleted due to no activity on 2025/10/24 22:16
Subsystems: mm
[Documentation on labels]
First crash: 226d, last: 189d
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in kvm_vm_ioctl kernel 1 1 921d 921d 0/29 auto-obsoleted due to no activity on 2023/09/23 08:44
upstream INFO: rcu detected stall in kvm_vm_ioctl (2) kernel 1 2 473d 488d 0/29 auto-obsoleted due to no activity on 2025/01/13 09:22

Sample crash report:
bridge0: received packet on veth0_to_bridge with own address as source address (addr:8a:82:7e:27:0a:fd, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P10396/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=47185, q=728 ncpus=2)
task:syz.5.1185      state:R  running task     stack:26696 pid:10396 tgid:10395 ppid:8987   task_flags:0x400040 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x16fd/0x4cf0 kernel/sched/core.c:6786
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7109
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x2b5/0x3e0 kernel/locking/lockdep.c:5896
Code: 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 eb 81 01 11 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000b956fb0 EFLAGS: 00000206
RAX: f4f9398697488600 RBX: 0000000000000202 RCX: f4f9398697488600
RDX: 0000000000000003 RSI: ffffffff8db845d7 RDI: ffffffff8be28dc0
RBP: ffff888025b4a968 R08: ffffc9000b9579e8 R09: 0000000000000000
R10: ffffc9000b957138 R11: fffff5200172ae29 R12: 0000000000000003
R13: 0000000000000003 R14: ffffffff8e13f0e0 R15: ffff888025b49e00
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:871 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680
 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:1248 [inline]
 __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2717 [inline]
 __put_partials+0x161/0x1c0 mm/slub.c:3186
 put_cpu_partial+0x17c/0x250 mm/slub.c:3261
 __slab_free+0x2f7/0x400 mm/slub.c:4513
 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:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 __do_kmalloc_node mm/slub.c:4327 [inline]
 __kmalloc_node_noprof+0x21b/0x4e0 mm/slub.c:4334
 kmalloc_node_noprof include/linux/slab.h:932 [inline]
 __vmalloc_area_node mm/vmalloc.c:3698 [inline]
 __vmalloc_node_range_noprof+0x5a9/0x12f0 mm/vmalloc.c:3893
 __vmalloc_node_noprof mm/vmalloc.c:3956 [inline]
 __vmalloc_noprof+0xb1/0xf0 mm/vmalloc.c:3970
 kvm_alloc_memslot_metadata arch/x86/kvm/x86.c:13051 [inline]
 kvm_arch_prepare_memory_region+0x33b/0xed0 arch/x86/kvm/x86.c:13128
 kvm_prepare_memory_region virt/kvm/kvm_main.c:1700 [inline]
 kvm_set_memslot+0x599/0x1310 virt/kvm/kvm_main.c:1930
 kvm_set_memory_region+0x9bb/0xc00 virt/kvm/kvm_main.c:2111
 kvm_vm_ioctl_set_memory_region+0x6f/0xa0 virt/kvm/kvm_main.c:2145
 kvm_vm_ioctl+0x957/0xc60 virt/kvm/kvm_main.c:5184
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff4ae18e5ab
RSP: 002b:00007ff4aef40490 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ff4aef40be0 RCX: 00007ff4ae18e5ab
RDX: 00007ff4aef40be0 RSI: 000000004020ae46 RDI: 0000000000000004
RBP: 0000000000000004 R08: 0000000000000001 R09: 0000000000000004
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000006
R13: 0000200000fee000 R14: 0000200000fe8000 R15: 00000000fec00000
 </TASK>
rcu: rcu_preempt kthread starved for 5715 jiffies! g47185 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27128 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x16fd/0x4cf0 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6879
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.16.0-rc7-syzkaller-00120-g5f33ebd2018c #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:trace_lock_release include/trace/events/lock.h:69 [inline]
RIP: 0010:lock_release+0x44/0x3e0 kernel/locking/lockdep.c:5882
Code: 8b 05 80 84 01 11 48 89 44 24 28 0f 1f 44 00 00 65 8b 05 83 84 01 11 83 f8 08 0f 83 9a 02 00 00 89 c0 48 0f a3 05 2c 92 03 0e <73> 16 e8 d5 df 08 00 84 c0 75 0d f6 05 56 75 ed 0d 01 0f 84 ad 02
RSP: 0018:ffffc90000a08218 EFLAGS: 00000297
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffff88801d2f5a00
RDX: 0000000000000100 RSI: ffffffff8a45b68e RDI: ffffffff8e13f0e0
RBP: ffffc90000a08388 R08: ffff88801d2f5a00 R09: 0000000000000004
R10: 0000000000000003 R11: 0000000000000100 R12: 1ffff92000141058
R13: ffffffff8a45b68e R14: ffffffff8e13f0e0 R15: ffffffff8a45b4b0
FS:  0000000000000000(0000) GS:ffff888125d23000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f021275dd58 CR3: 000000003512a000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:871 [inline]
 nf_hook include/linux/netfilter.h:274 [inline]
 NF_HOOK+0x2ed/0x3c0 include/linux/netfilter.h:315
 __br_forward+0x41e/0x600 net/bridge/br_forward.c:115
 br_handle_frame_finish+0x14b4/0x19b0 net/bridge/br_input.c:221
 nf_hook_bridge_pre net/bridge/br_input.c:305 [inline]
 br_handle_frame+0xb89/0x14c0 net/bridge/br_input.c:434
 __netif_receive_skb_core+0x10e1/0x4180 net/core/dev.c:5863
 __netif_receive_skb_one_core net/core/dev.c:5975 [inline]
 __netif_receive_skb+0x72/0x380 net/core/dev.c:6090
 process_backlog+0x60e/0x14f0 net/core/dev.c:6442
 __napi_poll+0xc4/0x480 net/core/dev.c:7414
 napi_poll net/core/dev.c:7478 [inline]
 net_rx_action+0x707/0xe30 net/core/dev.c:7605
 handle_softirqs+0x286/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 93 de 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d d3 8d 1a 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c2
RAX: 3c3bd4cdfb9ba400 RBX: ffffffff81976a28 RCX: 3c3bd4cdfb9ba400
RDX: 0000000000000001 RSI: ffffffff8d99696d RDI: ffffffff8be28dc0
RBP: ffffc90000197f20 R08: ffff8880b8732f5b R09: 1ffff110170e65eb
R10: dffffc0000000000 R11: ffffed10170e65ec R12: ffffffff8fa1ddf0
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff11003a5eb40
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:749
 default_idle_call+0x74/0xb0 kernel/sched/idle.c:117
 cpuidle_idle_call kernel/sched/idle.c:185 [inline]
 do_idle+0x1e8/0x510 kernel/sched/idle.c:325
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
 common_startup_64+0x13e/0x147
 </TASK>
net_ratelimit: 36797 callbacks suppressed
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:8a:82:7e:27:0a:fd, 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)
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: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: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:8a:82:7e:27:0a:fd, vlan:0)
net_ratelimit: 50552 callbacks suppressed
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 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:8a:82:7e:27:0a:fd, 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)
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: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:aa:aa:aa:aa:aa:0c, vlan:0)

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/26 22:14 upstream 5f33ebd2018c fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in kvm_vm_ioctl
2025/07/02 20:18 upstream b4911fb0b060 0cd59a8f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in kvm_vm_ioctl
2025/06/27 03:08 upstream e34a79b96ab9 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in kvm_vm_ioctl
2025/06/20 03:31 upstream 24770983ccfe ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in kvm_vm_ioctl
* Struck through repros no longer work on HEAD.