Re: [ 0.003333] BUG: KASAN: use-after-scope in console_unlock+0x605/0xcc0

Fengguang Wu
2017-11-30T09:05:57Z

On Thu, Nov 30, 2017 at 05:29:09PM +0900, Sergey Senozhatsky wrote:
>On (11/30/17 09:16), Dmitry Vyukov wrote:
>[..]
>> > to be honest, this backtrace hardly makes any sense to me.
>> >
>> > vprintk_emit()
>> > reserve_standard_io_resources()
>> > __flush_tlb_all()
>> > vprintk_emit()
>> > __down_trylock_console_sem()
>> > wake_up_klogd()
>> > console_unlock()
>> >
>> > I need some help here.
>>
>>
>> You can try dirty patch from here:
>> https://groups.google.com/d/msg/kasan-dev/iDb5bhcMBT0/55QzwWaHAwAJ
>> It should make KASAN print the exact variable name and frame where it
>> was allocated.
>
>would be good if Fengguang can try this out. I can't reproduce the
>problem on my x86 box (linux-next and Linus's trees both work fine
>for me with KASAN + lockdep + TRACE_IRQ).

OK I'll try Dmitry's patch out.

Thanks,
Fengguang