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INFO: rcu detected stall in __alloc_skb (3)

Status: auto-obsoleted due to no activity on 2023/01/16 19:06
Subsystems: net
[Documentation on labels]
First crash: 1202d, last: 1202d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in __alloc_skb net 1 2 2731d 2730d 0/29 closed as invalid on 2018/09/11 09:33
upstream INFO: rcu detected stall in __alloc_skb (2) fs mm 1 3 1406d 1406d 0/29 auto-closed as invalid on 2022/06/24 21:19
upstream INFO: rcu detected stall in __alloc_skb (4) kasan mm 1 1 121d 121d 0/29 auto-obsoleted due to no activity on 2026/01/30 03:22
upstream BUG: soft lockup in __alloc_skb mm 1 1 1052d 1052d 0/29 auto-obsoleted due to no activity on 2023/08/19 06:32

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=3e34/1/0x4000000000000000 softirq=26335/26336 fqs=2475
	(detected by 0, t=10502 jiffies, g=36741, q=1288 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5343 Comm: kworker/1:3 Not tainted 6.1.0-rc5-next-20221115-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Workqueue: events nsim_dev_trap_report_work
RIP: 0010:rcu_rdp_cpu_online kernel/rcu/tree.c:3941 [inline]
RIP: 0010:rcu_lockdep_current_cpu_online kernel/rcu/tree.c:3975 [inline]
RIP: 0010:rcu_lockdep_current_cpu_online+0x87/0x140 kernel/rcu/tree.c:3959
Code: 3c 02 00 0f 85 a4 00 00 00 48 03 1c ed 00 79 03 8c 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 20 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 87 00 00 00 48 8d 7b 18 48 8b 6b 20 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc900001e0c38 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffff8880b9b3c200 RCX: ffffffff816378b9
RDX: 1ffff11017367844 RSI: 0000000000010005 RDI: ffff8880b9b3c220
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8e54b797
R10: fffffbfff1ca96f2 R11: 0000000000000000 R12: 0000000000000001
R13: ffffffff8a4eb020 R14: 0000000000000001 R15: ffff88807d0cb340
FS:  0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007facb448b038 CR3: 0000000021a1c000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_read_lock_held_common kernel/rcu/update.c:112 [inline]
 rcu_read_lock_held_common kernel/rcu/update.c:102 [inline]
 rcu_read_lock_sched_held+0x29/0x70 kernel/rcu/update.c:123
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0x5cf/0x810 kernel/locking/lockdep.c:5679
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
 _raw_spin_unlock_irqrestore+0x1a/0x70 kernel/locking/spinlock.c:194
 debug_object_deactivate lib/debugobjects.c:761 [inline]
 debug_object_deactivate+0x268/0x300 lib/debugobjects.c:727
 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
 debug_deactivate kernel/time/hrtimer.c:481 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1653 [inline]
 __hrtimer_run_queues+0x422/0xfb0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x320/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline]
 __sysvec_apic_timer_interrupt+0x180/0x640 arch/x86/kernel/apic/apic.c:1113
 sysvec_apic_timer_interrupt+0x92/0xc0 arch/x86/kernel/apic/apic.c:1107
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:memset_erms+0xd/0x20 arch/x86/lib/memset_64.S:64
Code: 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 66 0f 1f 00 49 89 f9 40 88 f0 48 89 d1 <f3> aa 4c 89 c8 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 66 0f 1f
RSP: 0018:ffffc90004c1fb70 EFLAGS: 00010246
RAX: ffff888029b40000 RBX: 0000000000001000 RCX: 0000000000000e40
RDX: 0000000000001000 RSI: 0000000000000000 RDI: ffff888029b401c0
RBP: ffff888012042140 R08: 0000000000000001 R09: ffff888029b40000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000082820
R13: 0000000000000001 R14: 0000000000001000 R15: 0000000000000000
 slab_post_alloc_hook mm/slab.h:763 [inline]
 slab_alloc_node mm/slub.c:3433 [inline]
 __kmem_cache_alloc_node+0x34d/0x430 mm/slub.c:3472
 __do_kmalloc_node mm/slab_common.c:954 [inline]
 __kmalloc_node_track_caller+0x4b/0xc0 mm/slab_common.c:975
 kmalloc_reserve net/core/skbuff.c:438 [inline]
 __alloc_skb+0xe9/0x310 net/core/skbuff.c:511
 alloc_skb include/linux/skbuff.h:1269 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:751 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:808 [inline]
 nsim_dev_trap_report_work+0x2b1/0xc80 drivers/net/netdevsim/dev.c:853
 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289
 worker_thread+0x669/0x1090 kernel/workqueue.c:2436
 kthread+0x2e8/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
rcu: rcu_preempt kthread starved for 5549 jiffies! g36741 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:28656 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5229 [inline]
 __schedule+0xb8a/0x5450 kernel/sched/core.c:6541
 schedule+0xde/0x1b0 kernel/sched/core.c:6617
 schedule_timeout+0x14e/0x2a0 kernel/time/timer.c:1935
 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1588
 rcu_gp_kthread+0x23a/0x360 kernel/rcu/tree.c:1787
 kthread+0x2e8/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 8288 Comm: syz-executor.0 Not tainted 6.1.0-rc5-next-20221115-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:csd_lock_wait kernel/smp.c:413 [inline]
RIP: 0010:smp_call_function_many_cond+0x43f/0x10a0 kernel/smp.c:987
Code: e6 e8 25 ec 0a 00 45 85 e4 74 48 48 8b 04 24 49 89 c5 83 e0 07 49 c1 ed 03 49 89 c4 4d 01 fd 41 83 c4 03 e8 53 ef 0a 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 4e 0a 00 00 8b 43 08 31
RSP: 0018:ffffc90005d9f818 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b9b41b40 RCX: 0000000000000000
RDX: ffff88807ccfba80 RSI: ffffffff8175ad2d RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000094001 R12: 0000000000000003
R13: ffffed1017368369 R14: 0000000000000001 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f15b1d13440 CR3: 000000002bd58000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x5a/0xa0 kernel/smp.c:1155
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:87 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:943 [inline]
 flush_tlb_mm_range+0x333/0x4d0 arch/x86/mm/tlb.c:1029
 tlb_flush arch/x86/include/asm/tlb.h:20 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:454 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:444 [inline]
 tlb_flush_mmu mm/mmu_gather.c:293 [inline]
 tlb_finish_mmu+0x338/0x7e0 mm/mmu_gather.c:386
 exit_mmap+0x202/0x7b0 mm/mmap.c:3105
 __mmput+0x128/0x4c0 kernel/fork.c:1207
 mmput+0x60/0x70 kernel/fork.c:1229
 exit_mm kernel/exit.c:516 [inline]
 do_exit+0x9ac/0x28d0 kernel/exit.c:807
 do_group_exit+0xd4/0x2a0 kernel/exit.c:950
 get_signal+0x21b1/0x2440 kernel/signal.c:2858
 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
 exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
 exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296
 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7ff9880b0361
Code: Unable to access opcode bytes at 0x7ff9880b0337.
RSP: 002b:00007ffe97bf73c0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 0000000000000169 RCX: 00007ff9880b0361
RDX: 00007ffe97bf7400 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe97bf748c R08: 0000000000000000 R09: 00007ffe97bfa080
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032
R13: 000000000007905a R14: 0000000000000001 R15: 00007ffe97bf74f0
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/11/16 11:23 linux-next 3c1f24109dfc 3a127a31 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in __alloc_skb
* Struck through repros no longer work on HEAD.