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INFO: rcu detected stall in sys_mlock (2)

Status: auto-obsoleted due to no activity on 2025/02/05 20:37
Subsystems: kasan mm
[Documentation on labels]
First crash: 378d, last: 366d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_mlock mm 1 1 514d 514d 0/29 auto-obsoleted due to no activity on 2024/09/11 05:27
linux-6.6 INFO: rcu detected stall in sys_mlock 1 1 53d 53d 0/2 upstream: reported on 2025/09/16 08:53
linux-5.15 INFO: rcu detected stall in sys_mlock 1 1 140d 140d 0/3 auto-obsoleted due to no activity on 2025/09/29 15:14
linux-6.1 INFO: rcu detected stall in sys_mlock 1 1 542d 542d 0/3 auto-obsoleted due to no activity on 2024/08/23 11:10

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P8436/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=25181, q=1616349 ncpus=2)
task:syz.5.579       state:R  running task     stack:27376 pid:8436  tgid:8427  ppid:7089   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0xe55/0x5730 kernel/sched/core.c:6690
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7012
 irqentry_exit+0x36/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0xc/0x70 kernel/kcov.c:217
Code: cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 65 48 8b 15 74 5b 76 7e <65> 8b 05 75 5b 76 7e a9 00 01 ff 00 48 8b 34 24 74 1d f6 c4 01 74
RSP: 0018:ffffc9000bc67218 EFLAGS: 00000297
RAX: 0000000000000002 RBX: ffff88801e138dc8 RCX: ffffffff81f8a3b6
RDX: ffff888064f33c00 RSI: 000000000000001f RDI: 0000000000000003
RBP: 000000000000000a R08: 0000000000000003 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88801e138df0
R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000000
 __update_page_owner_handle+0x96/0x320 mm/page_owner.c:242
 __set_page_owner+0x13f/0x560 mm/page_owner.c:325
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1545 [inline]
 get_page_from_freelist+0x101e/0x3070 mm/page_alloc.c:3457
 __alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4733
 alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
 folio_alloc_mpol_noprof+0x36/0xd0 mm/mempolicy.c:2283
 vma_alloc_folio_noprof+0xee/0x1b0 mm/mempolicy.c:2314
 folio_prealloc mm/memory.c:1062 [inline]
 alloc_anon_folio mm/memory.c:4716 [inline]
 do_anonymous_page mm/memory.c:4773 [inline]
 do_pte_missing+0x2010/0x3e50 mm/memory.c:3963
 handle_pte_fault mm/memory.c:5755 [inline]
 __handle_mm_fault+0x100a/0x2a10 mm/memory.c:5898
 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6066
 faultin_page mm/gup.c:1187 [inline]
 __get_user_pages+0x90f/0x3b90 mm/gup.c:1485
 populate_vma_page_range+0x27f/0x3a0 mm/gup.c:1923
 __mm_populate+0x1d6/0x380 mm/gup.c:2026
 do_mlock+0x412/0x7d0 mm/mlock.c:653
 __do_sys_mlock mm/mlock.c:661 [inline]
 __se_sys_mlock mm/mlock.c:659 [inline]
 __x64_sys_mlock+0x59/0x80 mm/mlock.c:659
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb48db7e719
RSP: 002b:00007fb48e8f1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000095
RAX: ffffffffffffffda RBX: 00007fb48dd36058 RCX: 00007fb48db7e719
RDX: 0000000000000000 RSI: 0000000000800000 RDI: 0000000020000000
RBP: 00007fb48dbf132e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb48dd36058 R15: 00007fffda4bb598
 </TASK>
rcu: rcu_preempt kthread starved for 3286 jiffies! g25181 f0x2 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:25600 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0xe55/0x5730 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6782
 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2615
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.12.0-rc4-syzkaller-00261-g850925a8133c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:stack_access_ok+0x14/0x200 arch/x86/kernel/unwind_orc.c:389
Code: 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 48 b8 00 00 00 00 00 fc ff df 41 57 41 56 4c 8d 77 08 41 55 <41> 54 49 89 d4 4c 89 f2 55 48 c1 ea 03 48 89 f5 53 48 89 fb 48 83
RSP: 0018:ffffc90000156a48 EFLAGS: 00000297
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffffff9185e080
RDX: 0000000000000008 RSI: ffffc900001578a0 RDI: ffffc90000156ad8
RBP: ffffc900001578a0 R08: 0000000000000001 R09: ffffffff9185e084
R10: ffffc90000156ad8 R11: 0000000000085343 R12: ffffc90000156b28
R13: ffffc90000156ad8 R14: ffffc90000156ae0 R15: ffffc900001578c0
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffcab891a8 CR3: 000000007e8fc000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline]
 unwind_next_frame+0x15dd/0x20c0 arch/x86/kernel/unwind_orc.c:648
 arch_stack_walk+0x95/0x100 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
 kmalloc_noprof include/linux/slab.h:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 ref_tracker_alloc+0x17c/0x5b0 lib/ref_tracker.c:203
 __netdev_tracker_alloc include/linux/netdevice.h:4062 [inline]
 netdev_hold include/linux/netdevice.h:4091 [inline]
 dst_init+0xda/0x580 net/core/dst.c:52
 dst_alloc+0xbb/0x1a0 net/core/dst.c:93
 rt_dst_alloc+0x35/0x3a0 net/ipv4/route.c:1612
 __mkroute_output net/ipv4/route.c:2573 [inline]
 ip_route_output_key_hash_rcu+0x8a5/0x2770 net/ipv4/route.c:2795
 ip_route_output_key_hash+0x138/0x2e0 net/ipv4/route.c:2624
 __ip_route_output_key include/net/route.h:141 [inline]
 ip_route_output_flow+0x27/0x150 net/ipv4/route.c:2852
 ip_route_output_key include/net/route.h:151 [inline]
 ip_route_me_harder+0x519/0x1290 net/ipv4/netfilter.c:53
 synproxy_send_tcp.isra.0+0x2fa/0x630 net/netfilter/nf_synproxy_core.c:431
 synproxy_send_client_synack+0x94c/0xcf0 net/netfilter/nf_synproxy_core.c:484
 nft_synproxy_eval_v4 net/netfilter/nft_synproxy.c:59 [inline]
 nft_synproxy_do_eval+0xa49/0xd60 net/netfilter/nft_synproxy.c:141
 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
 nft_do_chain+0x2e6/0x18f0 net/netfilter/nf_tables_core.c:288
 nft_do_chain_inet+0x18b/0x350 net/netfilter/nft_chain_filter.c:161
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xbb/0x200 net/netfilter/core.c:626
 nf_hook.constprop.0+0x42e/0x750 include/linux/netfilter.h:269
 NF_HOOK include/linux/netfilter.h:312 [inline]
 ip_local_deliver+0x169/0x1f0 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:460 [inline]
 ip_rcv_finish net/ipv4/ip_input.c:449 [inline]
 NF_HOOK include/linux/netfilter.h:314 [inline]
 NF_HOOK include/linux/netfilter.h:308 [inline]
 ip_rcv+0x2c3/0x5d0 net/ipv4/ip_input.c:569
 __netif_receive_skb_one_core+0x199/0x1e0 net/core/dev.c:5666
 __netif_receive_skb+0x1d/0x160 net/core/dev.c:5779
 process_backlog+0x443/0x15f0 net/core/dev.c:6111
 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:6775
 napi_poll net/core/dev.c:6844 [inline]
 net_rx_action+0xa92/0x1010 net/core/dev.c:6966
 handle_softirqs+0x213/0x8f0 kernel/softirq.c:554
 run_ksoftirqd kernel/softirq.c:927 [inline]
 run_ksoftirqd+0x3a/0x60 kernel/softirq.c:919
 smpboot_thread_fn+0x661/0xa30 kernel/smpboot.c:164
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/26 14:24 upstream 850925a8133c 65e8686b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in sys_mlock
2024/11/07 20:35 linux-next 74741a050b79 c069283c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in sys_mlock
* Struck through repros no longer work on HEAD.