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INFO: rcu detected stall in mld_dad_work (2)

Status: auto-obsoleted due to no activity on 2024/04/28 18:46
Subsystems: net
[Documentation on labels]
First crash: 866d, last: 866d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in mld_dad_work (4) net 1 syz 2 160d 197d 0/29 closed as invalid on 2026/04/30 15:35
upstream INFO: rcu detected stall in mld_dad_work (3) mm 1 2 297d 308d 0/29 auto-obsoleted due to no activity on 2025/11/18 11:46
upstream INFO: rcu detected stall in mld_dad_work net 1 C error 3 1052d 1169d 0/29 closed as invalid on 2023/09/22 04:28
android-5-15 BUG: soft lockup in mld_dad_work origin:lts 1 syz 1 639d 639d 0/2 auto-obsoleted due to no activity on 2024/12/11 14:40

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=601857, q=588 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10385 (4295281477-4295271092), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10385 jiffies! g601857 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:27776 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5400 [inline]
 __schedule+0xf12/0x5c00 kernel/sched/core.c:6727
 __schedule_loop kernel/sched/core.c:6802 [inline]
 schedule+0xe9/0x270 kernel/sched/core.c:6817
 schedule_timeout+0x137/0x290 kernel/time/timer.c:2183
 rcu_gp_fqs_loop+0x1ec/0xb10 kernel/rcu/tree.c:1663
 rcu_gp_kthread+0x24b/0x380 kernel/rcu/tree.c:1862
 kthread+0x2c6/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </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 PID: 4808 Comm: kworker/0:3 Not tainted 6.8.0-rc1-syzkaller-00455-gc57e32fb29f2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Workqueue: mld mld_dad_work
RIP: 0010:trylock_clear_pending kernel/locking/qspinlock_paravirt.h:121 [inline]
RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:435 [inline]
RIP: 0010:__pv_queued_spin_lock_slowpath+0x3ff/0xc70 kernel/locking/qspinlock.c:511
Code: 41 83 e4 07 41 bd 01 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8d 3c 01 eb 0c f3 90 41 83 ee 01 0f 84 c2 04 00 00 41 0f b6 07 <44> 38 e0 7f 08 84 c0 0f 85 00 06 00 00 0f b6 03 84 c0 75 dc be 02
RSP: 0018:ffffc90000007710 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffff8880783204c0 RCX: 1ffff1100f064098
RDX: 0000000000000001 RSI: ffffffff8a9291b9 RDI: ffffffff8b2fdf00
RBP: ffff8880b983db40 R08: 0000000000000001 R09: fffffbfff242b409
R10: ffffffff9215a04f R11: 0000000000000007 R12: 0000000000000000
R13: 0000000000000001 R14: 000000000000139b R15: ffffed100f064098
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31f22000 CR3: 000000000cf78000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x20e/0x2b0 kernel/locking/spinlock_debug.c:116
 spin_lock include/linux/spinlock.h:351 [inline]
 __netif_tx_lock include/linux/netdevice.h:4452 [inline]
 __dev_queue_xmit+0x1ab3/0x3ed0 net/core/dev.c:4347
 dev_queue_xmit include/linux/netdevice.h:3171 [inline]
 can_send+0x776/0xb40 net/can/af_can.c:276
 can_can_gw_rcv+0x74c/0xab0 net/can/gw.c:561
 deliver net/can/af_can.c:572 [inline]
 can_rcv_filter+0x15e/0x8e0 net/can/af_can.c:599
 can_receive+0x320/0x5c0 net/can/af_can.c:663
 can_rcv+0x1dc/0x270 net/can/af_can.c:687
 __netif_receive_skb_one_core+0x115/0x180 net/core/dev.c:5534
 __netif_receive_skb+0x1f/0x1b0 net/core/dev.c:5648
 process_backlog+0x101/0x6b0 net/core/dev.c:5976
 __napi_poll.constprop.0+0xb4/0x540 net/core/dev.c:6576
 napi_poll net/core/dev.c:6645 [inline]
 net_rx_action+0x956/0xe90 net/core/dev.c:6778
 __do_softirq+0x21a/0x8de kernel/softirq.c:553
 invoke_softirq kernel/softirq.c:427 [inline]
 __irq_exit_rcu kernel/softirq.c:632 [inline]
 irq_exit_rcu+0xb7/0x120 kernel/softirq.c:644
 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1076
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0xd/0x60 kernel/kcov.c:207
Code: fa 48 8b be b0 01 00 00 e8 b0 ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 65 48 8b 14 25 80 c2 03 00 <65> 8b 05 a4 9e 7b 7e a9 00 01 ff 00 48 8b 34 24 74 0f f6 c4 01 74
RSP: 0018:ffffc9000367f668 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00000000518a4000 RCX: ffffffff813b8bac
RDX: ffff88807c440000 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000004 R12: 0000000000000000
R13: ffffffff81e052e3 R14: ffff888013042140 R15: ffffc9000367f6f8
 __phys_addr+0xc6/0x140 arch/x86/mm/physaddr.c:31
 virt_to_folio include/linux/mm.h:1292 [inline]
 virt_to_slab mm/slab.h:204 [inline]
 ___cache_free+0x24/0xf0 mm/slub.c:4319
 qlink_free mm/kasan/quarantine.c:160 [inline]
 qlist_free_all+0x58/0x150 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:324
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3813 [inline]
 slab_alloc_node mm/slub.c:3860 [inline]
 kmem_cache_alloc_node+0x177/0x340 mm/slub.c:3903
 __alloc_skb+0x287/0x330 net/core/skbuff.c:641
 alloc_skb include/linux/skbuff.h:1296 [inline]
 alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6394
 sock_alloc_send_pskb+0x7e4/0x970 net/core/sock.c:2794
 sock_alloc_send_skb include/net/sock.h:1855 [inline]
 mld_newpack.isra.0+0x1ed/0x790 net/ipv6/mcast.c:1746
 add_grhead+0x295/0x340 net/ipv6/mcast.c:1849
 add_grec+0x111a/0x1670 net/ipv6/mcast.c:1987
 mld_send_initial_cr.part.0+0xe2/0x260 net/ipv6/mcast.c:2233
 mld_send_initial_cr net/ipv6/mcast.c:2224 [inline]
 mld_dad_work+0x57/0x2e0 net/ipv6/mcast.c:2259
 process_one_work+0x886/0x15d0 kernel/workqueue.c:2633
 process_scheduled_works kernel/workqueue.c:2706 [inline]
 worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787
 kthread+0x2c6/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/01/29 18:37 net-next c57e32fb29f2 991a98f4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in mld_dad_work
* Struck through repros no longer work on HEAD.