INFO: rcu detected stall in dst_destroy (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c37da90e Linux 4.19.143
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=12266bae900000
kernel config: https://syzkaller.appspot.com/x/.config?x=d162ec57805c4e4d
dashboard link: https://syzkaller.appspot.com/bug?extid=ac51d3fbafc31a2eb8ea
compiler: gcc (GCC) 10.1.0-syz 20200507

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ac51d3...@syzkaller.appspotmail.com

ptrace attach of "/root/syz-executor.0"[23119] was attempted by "/root/syz-executor.0"[23120]
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 0-....: (10499 ticks this GP) idle=7b2/1/0x4000000000000004 softirq=165123/165123 fqs=5108
rcu: (t=10500 jiffies g=186813 q=152197)
NMI backtrace for cpu 0
CPU: 0 PID: 22996 Comm: syz-executor.5 Not tainted 4.19.143-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1fc/0x2fe lib/dump_stack.c:118
nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x1a6/0x1eb lib/nmi_backtrace.c:62
trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
rcu_dump_cpu_stacks+0x15f/0x19c kernel/rcu/tree.c:1340
print_cpu_stall kernel/rcu/tree.c:1478 [inline]
check_cpu_stall kernel/rcu/tree.c:1550 [inline]
__rcu_pending kernel/rcu/tree.c:3293 [inline]
rcu_pending kernel/rcu/tree.c:3336 [inline]
rcu_check_callbacks.cold+0x62d/0xe19 kernel/rcu/tree.c:2682
update_process_times+0x2a/0xb0 kernel/time/timer.c:1650
tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:168
tick_sched_timer+0xfc/0x290 kernel/time/tick-sched.c:1278
__run_hrtimer kernel/time/hrtimer.c:1401 [inline]
__hrtimer_run_queues+0x3f6/0xe60 kernel/time/hrtimer.c:1463
hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1521
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline]
smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline]
RIP: 0010:kmem_cache_free+0x11c/0x260 mm/slab.c:3766
Code: 11 48 63 75 74 48 89 df e8 a1 3d c1 01 e9 68 ff ff ff e8 a7 4b cf ff 48 83 3d a7 c2 32 07 00 0f 84 f8 00 00 00 4c 89 e7 57 9d <0f> 1f 44 00 00 eb 86 65 8b 05 76 e8 61 7e 83 f8 3f 0f 87 e7 00 00
RSP: 0018:ffff8880ae607db0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000007 RBX: ffff888048fd3700 RCX: 1ffff110140f21a5
RDX: 0000000000000000 RSI: ffff8880a0790d30 RDI: 0000000000000282
RBP: ffff88821b35ac40 R08: 0000000000400000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000282
R13: ffffffff85bb665c R14: ffff888048fd3708 R15: ffff888048fd3738
dst_destroy+0x2bc/0x400 net/core/dst.c:141
__rcu_reclaim kernel/rcu/rcu.h:236 [inline]
rcu_do_batch kernel/rcu/tree.c:2584 [inline]
invoke_rcu_callbacks kernel/rcu/tree.c:2897 [inline]
__rcu_process_callbacks kernel/rcu/tree.c:2864 [inline]
rcu_process_callbacks+0x8ff/0x18b0 kernel/rcu/tree.c:2881
__do_softirq+0x26c/0x9a0 kernel/softirq.c:292
invoke_softirq kernel/softirq.c:372 [inline]
irq_exit+0x215/0x260 kernel/softirq.c:412
exiting_irq arch/x86/include/asm/apic.h:544 [inline]
smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1094
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
</IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa3/0xe0 kernel/locking/spinlock.c:184
Code: 48 c7 c0 48 5b d2 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 2f 48 83 3d bc bd 94 01 00 74 15 48 89 df 57 9d <0f> 1f 44 00 00 eb b2 e8 5a c1 c2 f9 eb c0 0f 0b 0f 0b 48 c7 c7 48
RSP: 0018:ffff888047ed7968 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff11a4b69 RBX: 0000000000000282 RCX: 1ffff110140f21a5
RDX: dffffc0000000000 RSI: ffff8880a0790d08 RDI: 0000000000000282
RBP: ffffffff8bad2188 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: dead000000000200
R13: ffff888024c00000 R14: 0000000000000011 R15: dffffc0000000000
__debug_check_no_obj_freed lib/debugobjects.c:798 [inline]
debug_check_no_obj_freed+0x201/0x482 lib/debugobjects.c:817
free_pages_prepare mm/page_alloc.c:1055 [inline]
__free_pages_ok+0x22d/0xd30 mm/page_alloc.c:1278
release_pages+0xab5/0x15a0 mm/swap.c:768
tlb_flush_mmu_free mm/memory.c:249 [inline]
tlb_flush_mmu+0x1dc/0x4f0 mm/memory.c:258
arch_tlb_finish_mmu mm/memory.c:273 [inline]
tlb_finish_mmu+0x108/0x200 mm/memory.c:432
unmap_region+0x2cd/0x3a0 mm/mmap.c:2572
do_munmap+0x603/0xde0 mm/mmap.c:2779
mremap_to mm/mremap.c:457 [inline]
__do_sys_mremap mm/mremap.c:552 [inline]
__se_sys_mremap+0xa61/0xf90 mm/mremap.c:515
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45d5b9
Code: 5d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f33f6384c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000019
RAX: ffffffffffffffda RBX: 0000000000021780 RCX: 000000000045d5b9
RDX: 0000000000800000 RSI: 0000000000002000 RDI: 0000000020a94000
RBP: 000000000118cf90 R08: 0000000020130000 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007fff025b69df R14: 00007f33f63859c0 R15: 000000000118cf4c


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.