INFO: rcu detected stall in inet_twsk_kill

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: d71f695c Linux 4.14.179
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=160a3f22100000
kernel config: https://syzkaller.appspot.com/x/.config?x=580f01c69a690433
dashboard link: https://syzkaller.appspot.com/bug?extid=0564175079db19fb04d6
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+056417...@syzkaller.appspotmail.com

INFO: rcu_preempt self-detected stall on CPU
0-...: (1 GPs behind) idle=022/140000000000002/0 softirq=197965/197967 fqs=54
(t=10500 jiffies g=50177 c=50176 q=2341)
NMI backtrace for cpu 0
CPU: 0 PID: 10877 Comm: syz-executor.1 Not tainted 4.14.179-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:17 [inline]
dump_stack+0x13e/0x194 lib/dump_stack.c:58
nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x139/0x17e lib/nmi_backtrace.c:62
trigger_single_cpu_backtrace include/linux/nmi.h:158 [inline]
rcu_dump_cpu_stacks+0x16d/0x1b8 kernel/rcu/tree.c:1396
print_cpu_stall kernel/rcu/tree.c:1542 [inline]
check_cpu_stall kernel/rcu/tree.c:1610 [inline]
__rcu_pending kernel/rcu/tree.c:3390 [inline]
rcu_pending kernel/rcu/tree.c:3452 [inline]
rcu_check_callbacks.cold+0x490/0xdaa kernel/rcu/tree.c:2792
update_process_times+0x29/0x60 kernel/time/timer.c:1590
tick_sched_handle+0x7d/0x150 kernel/time/tick-sched.c:165
tick_sched_timer+0x3e/0x120 kernel/time/tick-sched.c:1223
__run_hrtimer kernel/time/hrtimer.c:1223 [inline]
__hrtimer_run_queues+0x25c/0xbb0 kernel/time/hrtimer.c:1287
hrtimer_interrupt+0x1e6/0x5e0 kernel/time/hrtimer.c:1321
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline]
smp_apic_timer_interrupt+0x117/0x5e0 arch/x86/kernel/apic/apic.c:1100
apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline]
RIP: 0010:kmem_cache_free+0xa9/0x2b0 mm/slab.c:3759
RSP: 0018:ffff8880aea07cb8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff10
RAX: 0000000000000007 RBX: ffff88809c20e700 RCX: 1ffff1101417256a
RDX: 0000000000000000 RSI: ffff8880a0b92b30 RDI: 0000000000000286
RBP: ffff8880a642ccc0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000286
R13: ffffffff854a6ef8 R14: ffff88809c20e700 R15: 000000000000ffff
inet_bind_bucket_destroy net/ipv4/inet_hashtables.c:89 [inline]
inet_bind_bucket_destroy+0xd8/0x110 net/ipv4/inet_hashtables.c:85
inet_twsk_bind_unhash+0x115/0x180 net/ipv4/inet_timewait_sock.c:38
inet_twsk_kill+0x316/0x430 net/ipv4/inet_timewait_sock.c:58
call_timer_fn+0x14a/0x650 kernel/time/timer.c:1279
expire_timers kernel/time/timer.c:1318 [inline]
__run_timers kernel/time/timer.c:1636 [inline]
__run_timers kernel/time/timer.c:1604 [inline]
run_timer_softirq+0x52a/0x1390 kernel/time/timer.c:1649
__do_softirq+0x254/0x9bf kernel/softirq.c:288
invoke_softirq kernel/softirq.c:368 [inline]
irq_exit+0x15b/0x1a0 kernel/softirq.c:409
exiting_irq arch/x86/include/asm/apic.h:648 [inline]
smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1102
apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792
</IRQ>
RIP: 0010:__read_once_size include/linux/compiler.h:183 [inline]
RIP: 0010:compound_head include/linux/page-flags.h:147 [inline]
RIP: 0010:release_pages+0x125/0xc00 mm/swap.c:779
RSP: 0018:ffff88804f7376d8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: 1ffffd40004bd27c RBX: ffffea00025e939c RCX: 0000000000000000
RDX: 0000000000000000 RSI: 00000000000001f8 RDI: ffff88809e971010
RBP: ffffea00025e93c0 R08: 0000000000000001 R09: 0000000000000000
R10: ffff8880a0b92b30 R11: ffff8880a0b92280 R12: ffffea00025e93e0
R13: 0000000000000000 R14: dffffc0000000000 R15: ffff88809e971fa8
tlb_flush_mmu_free+0x73/0x130 mm/memory.c:260
zap_pte_range mm/memory.c:1409 [inline]
zap_pmd_range mm/memory.c:1444 [inline]
zap_pud_range mm/memory.c:1473 [inline]
zap_p4d_range mm/memory.c:1494 [inline]
unmap_page_range+0x1308/0x1930 mm/memory.c:1515
unmap_single_vma+0x147/0x2b0 mm/memory.c:1560
unmap_vmas+0x9d/0x160 mm/memory.c:1590
exit_mmap+0x26d/0x4b0 mm/mmap.c:3056
__mmput kernel/fork.c:930 [inline]
mmput+0x103/0x420 kernel/fork.c:951
exit_mm kernel/exit.c:545 [inline]
do_exit+0x933/0x2b00 kernel/exit.c:845
do_group_exit+0x100/0x310 kernel/exit.c:955
get_signal+0x385/0x1ca0 kernel/signal.c:2423
do_signal+0x7c/0x1690 arch/x86/kernel/signal.c:814
exit_to_usermode_loop+0x159/0x220 arch/x86/entry/common.c:160
prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45c829
RSP: 002b:00007fc22e3a9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: 0000000000000000 RBX: 0000000000509f60 RCX: 000000000045c829
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000c020400
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000c4e R14: 00000000004ce7bd R15: 00007fc22e3aa6d4


---
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[syzbot]

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