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INFO: rcu detected stall in sys_migrate_pages (3)

Status: auto-obsoleted due to no activity on 2026/07/04 15:07
Subsystems: mm
Labels: prio:high
[Documentation on labels]
First crash: 97d, last: 97d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
3dbc491a-f858-4348-9d75-6819fe54e23d assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ✅ PeripheralTrigger: ❌ RemoteTrigger: ✅ Unprivileged: ❌ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ INFO: rcu detected stall in sys_migrate_pages (3) 2026/05/19 19:29 2026/05/19 19:44 2026/05/19 20:23 1d9407ad5a662c921fc0d659cf022b438c0bde91

			
		
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_migrate_pages mm 1 1 1324d 1324d 0/29 auto-obsoleted due to no activity on 2023/02/26 14:28
upstream INFO: rcu detected stall in sys_migrate_pages (2) mm 1 1 765d 765d 0/29 auto-obsoleted due to no activity on 2024/09/05 08:59

Sample crash report:
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:7a:e7:75:60:4f:b0, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P18074/2:b..l P6976/1:b..l P18093/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=140765, q=1141 ncpus=1)
task:syz.4.2715      state:R  running task     stack:27088 pid:18093 tgid:18072 ppid:6982   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0xfee/0x6120 kernel/sched/core.c:6911
 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7238
 irqentry_exit+0x17b/0x670 kernel/entry/common.c:239
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x19e/0x320 kernel/locking/lockdep.c:5893
Code: ff 65 0f c1 05 cb cd 29 12 83 f8 01 0f 85 3d 01 00 00 9c 58 f6 c4 02 0f 85 28 01 00 00 41 f7 c6 00 02 00 00 0f 85 de 00 00 00 <48> 8b 44 24 10 65 48 2b 05 1d 86 29 12 0f 85 63 01 00 00 48 83 c4
RSP: 0018:ffffc90003af75d8 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e7e7760 RCX: ffffc90003af75e4
RDX: 0000000000000000 RSI: ffffffff8de5cf1b RDI: ffffffff8c1b1da0
RBP: ffffffff827f17ae R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880335bbd00
R13: 0000000000000381 R14: 0000000000000202 R15: 0000000000000001
 rcu_lock_release include/linux/rcupdate.h:322 [inline]
 rcu_read_unlock include/linux/rcupdate.h:881 [inline]
 __folio_copy_owner+0x413/0x660 mm/page_owner.c:422
 folio_copy_owner include/linux/page_owner.h:44 [inline]
 folio_migrate_flags+0xedd/0x13f0 mm/migrate.c:844
 __migrate_folio.isra.0+0x38d/0x4c0 mm/migrate.c:876
 move_to_new_folio+0x29b/0x4e0 mm/migrate.c:1100
 migrate_folio_move mm/migrate.c:1374 [inline]
 migrate_folios_move mm/migrate.c:1721 [inline]
 migrate_pages_batch+0x1872/0x4530 mm/migrate.c:1977
 migrate_pages_sync+0x12c/0x880 mm/migrate.c:2007
 migrate_pages+0x1aae/0x28a0 mm/migrate.c:2116
 migrate_to_node mm/mempolicy.c:1319 [inline]
 do_migrate_pages+0x488/0x740 mm/mempolicy.c:1418
 kernel_migrate_pages+0x560/0x700 mm/mempolicy.c:1932
 __do_sys_migrate_pages mm/mempolicy.c:1950 [inline]
 __se_sys_migrate_pages mm/mempolicy.c:1946 [inline]
 __x64_sys_migrate_pages+0x96/0x100 mm/mempolicy.c:1946
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9047d9c819
RSP: 002b:00007f9048bbf028 EFLAGS: 00000246 ORIG_RAX: 0000000000000100
RAX: ffffffffffffffda RBX: 00007f9048016270 RCX: 00007f9047d9c819
RDX: 0000200000000100 RSI: 000000000000000a RDI: 0000000000000000
RBP: 00007f9047e32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000140 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9048016308 R14: 00007f9048016270 R15: 00007ffe2e211a48
 </TASK>
task:syz-executor    state:R  running task     stack:25416 pid:6976  tgid:6976  ppid:5810   task_flags:0x40050c flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0xfee/0x6120 kernel/sched/core.c:6911
 preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7095
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
 _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:389 [inline]
 zap_pte_range mm/memory.c:1959 [inline]
 zap_pmd_range mm/memory.c:2021 [inline]
 zap_pud_range mm/memory.c:2049 [inline]
 zap_p4d_range mm/memory.c:2070 [inline]
 unmap_page_range+0x152f/0x4840 mm/memory.c:2091
 unmap_single_vma+0x153/0x240 mm/memory.c:2133
 unmap_vmas+0x295/0x590 mm/memory.c:2171
 exit_mmap+0x1ef/0xa30 mm/mmap.c:1302
 __mmput+0x12a/0x410 kernel/fork.c:1175
 mmput+0x67/0x80 kernel/fork.c:1198
 exit_mm kernel/exit.c:581 [inline]
 do_exit+0x819/0x2b60 kernel/exit.c:964
 do_group_exit+0xd5/0x2a0 kernel/exit.c:1118
 get_signal+0x1ec7/0x21e0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x91/0x770 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x86/0x4a0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
 do_syscall_64+0x668/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9047d57997
RSP: 002b:00007ffe2e211f30 EFLAGS: 00000202 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 00005555894cb500 RCX: 00007f9047d57997
RDX: 0000000040000000 RSI: 00007ffe2e211f8c RDI: ffffffffffffffff
RBP: 00007ffe2e211f8c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffe2e2121e8 R15: 0000000000000000
 </TASK>
task:syz.4.2715      state:R  running task     stack:26248 pid:18074 tgid:18072 ppid:6982   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0xfee/0x6120 kernel/sched/core.c:6911
 preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7095
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __local_bh_enable_ip+0xff/0x120 kernel/softirq.c:457
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 ip6t_do_table+0xbfa/0x1c90 net/ipv6/netfilter/ip6_tables.c:375
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_slow+0xbf/0x220 net/netfilter/core.c:623
 nf_hook include/linux/netfilter.h:273 [inline]
 __ip6_local_out+0x4c0/0xaf0 net/ipv6/output_core.c:140
 ip6_local_out+0x2a/0x1f0 net/ipv6/output_core.c:150
 ip6_send_skb+0x112/0x430 net/ipv6/ip6_output.c:1984
 ip6_push_pending_frames+0x3b/0x50 net/ipv6/ip6_output.c:2005
 rawv6_push_pending_frames net/ipv6/raw.c:589 [inline]
 rawv6_sendmsg+0x2d0c/0x4420 net/ipv6/raw.c:919
 inet_sendmsg+0x11c/0x140 net/ipv4/af_inet.c:865
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0x98d/0xb70 net/socket.c:2592
 ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646
 __sys_sendmmsg+0x205/0x430 net/socket.c:2735
 __do_sys_sendmmsg net/socket.c:2762 [inline]
 __se_sys_sendmmsg net/socket.c:2759 [inline]
 __x64_sys_sendmmsg+0x9c/0x100 net/socket.c:2759
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9047d9c819
RSP: 002b:00007f9048c01028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f9048016090 RCX: 00007f9047d9c819
RDX: 00000000000009a6 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f9047e32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000007000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9048016128 R14: 00007f9048016090 R15: 00007ffe2e211a48
 </TASK>
rcu: rcu_preempt kthread starved for 5739 jiffies! g140765 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:27832 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0xfee/0x6120 kernel/sched/core.c:6911
 __schedule_loop kernel/sched/core.c:6993 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7008
 schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095
 rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 15642 Comm: kworker/u8:17 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: bat_events batadv_dat_purge
RIP: 0010:lock_acquire+0x5e/0x380 kernel/locking/lockdep.c:5872
Code: 05 3b 8d 29 12 83 f8 07 0f 87 f0 00 00 00 48 0f a3 05 06 8b f5 0e 0f 82 c2 02 00 00 8b 35 ce be f5 0e 85 f6 0f 85 dd 00 00 00 <48> 8b 44 24 30 65 48 2b 05 dd 8c 29 12 0f 85 02 03 00 00 48 83 c4
RSP: 0018:ffffc90000006aa0 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000005
RDX: 0000000000000000 RSI: ffffffff8de5cf1b RDI: ffffffff8c1b1da0
RBP: ffffffff8e7e7760 R08: 000000005970cd9e R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888124340000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000002000 CR3: 000000000e598000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 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+0xd1/0x1ea0 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2685 [inline]
 slab_free mm/slub.c:6165 [inline]
 kmem_cache_free+0x124/0x6a0 mm/slub.c:6295
 kfree_skbmem+0x19a/0x210 net/core/skbuff.c:1151
 __kfree_skb net/core/skbuff.c:1218 [inline]
 sk_skb_reason_drop+0x10f/0x1b0 net/core/skbuff.c:1255
 kfree_skb_reason include/linux/skbuff.h:1322 [inline]
 kfree_skb include/linux/skbuff.h:1331 [inline]
 ip6_mc_input+0x832/0xf50 net/ipv6/ip6_input.c:593
 dst_input include/net/dst.h:480 [inline]
 ip6_rcv_finish+0x294/0x300 net/ipv6/ip6_input.c:79
 ip_sabotage_in+0x21e/0x290 net/bridge/br_netfilter_hooks.c:990
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_slow+0xbf/0x220 net/netfilter/core.c:623
 nf_hook.constprop.0+0x2a6/0x750 include/linux/netfilter.h:273
 NF_HOOK include/linux/netfilter.h:316 [inline]
 ipv6_rcv+0xa4/0x3d0 net/ipv6/ip6_input.c:311
 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:6181
 __netif_receive_skb+0x1f/0x120 net/core/dev.c:6294
 netif_receive_skb_internal net/core/dev.c:6380 [inline]
 netif_receive_skb+0x139/0x820 net/core/dev.c:6439
 NF_HOOK include/linux/netfilter.h:318 [inline]
 NF_HOOK include/linux/netfilter.h:312 [inline]
 br_pass_frame_up+0x346/0x490 net/bridge/br_input.c:70
 br_handle_frame_finish+0xa74/0x1f60 net/bridge/br_input.c:235
 br_nf_hook_thresh+0x30d/0x420 net/bridge/br_netfilter_hooks.c:1167
 br_nf_pre_routing_finish_ipv6+0x769/0xfb0 net/bridge/br_netfilter_ipv6.c:154
 NF_HOOK include/linux/netfilter.h:318 [inline]
 br_nf_pre_routing_ipv6+0x39c/0x8b0 net/bridge/br_netfilter_ipv6.c:184
 br_nf_pre_routing+0x90d/0x1550 net/bridge/br_netfilter_hooks.c:508
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:291 [inline]
 br_handle_frame+0xcdd/0x1520 net/bridge/br_input.c:442
 __netif_receive_skb_core.constprop.0+0x6c5/0x3550 net/core/dev.c:6068
 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:6179
 __netif_receive_skb+0x1f/0x120 net/core/dev.c:6294
 process_backlog+0x37a/0x1580 net/core/dev.c:6645
 __napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7709
 napi_poll net/core/dev.c:7772 [inline]
 net_rx_action+0xa40/0xf20 net/core/dev.c:7929
 handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
 do_softirq kernel/softirq.c:523 [inline]
 do_softirq+0xac/0xe0 kernel/softirq.c:510
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:450
 spin_unlock_bh include/linux/spinlock.h:395 [inline]
 __batadv_dat_purge.part.0+0x294/0x3c0 net/batman-adv/distributed-arp-table.c:185
 __batadv_dat_purge net/batman-adv/distributed-arp-table.c:166 [inline]
 batadv_dat_purge+0x4b/0xa0 net/batman-adv/distributed-arp-table.c:204
 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
 process_scheduled_works kernel/workqueue.c:3359 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
net_ratelimit: 5671 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:7a:e7:75:60:4f:b0, 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: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:7a:e7:75:60:4f:b0, 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: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:7a:e7:75:60:4f:b0, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
net_ratelimit: 10382 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:7a:e7:75:60:4f:b0, 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: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:7a:e7:75:60:4f:b0, 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: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:7a:e7:75:60:4f:b0, 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 (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/05 14:58 upstream 3aae9383f42f 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in sys_migrate_pages
* Struck through repros no longer work on HEAD.