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Subject: Re: WARNING and PANIC in irq_matrix_free
To: Thomas Gleixner <tglx@linutronix.de>
CC: Song Liu <songliubraving@fb.com>, Song Liu <liu.song.a23@gmail.com>,
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From: Dou Liyang <douly.fnst@cn.fujitsu.com>
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Date: Mon, 4 Jun 2018 19:59:38 +0800
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Hi Thomas,

At 06/04/2018 07:17 PM, Thomas Gleixner wrote:
> On Mon, 4 Jun 2018, Dou Liyang wrote:
>> Here, why didn't we avoid this cleanup by
>>
>> diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
>> index a75de0792942..0cc59646755f 100644
>> --- a/arch/x86/kernel/apic/vector.c
>> +++ b/arch/x86/kernel/apic/vector.c
>> @@ -821,6 +821,9 @@ static void free_moved_vector(struct apic_chip_data
>> *apicd)
>>           */
>>          WARN_ON_ONCE(managed);
>>
>> +       if (!vector)
>> +               return;
>> +
>>          trace_vector_free_moved(apicd->irq, cpu, vector, managed);
>>          irq_matrix_free(vector_matrix, cpu, vector, managed);
>>          per_cpu(vector_irq, cpu)[vector] = VECTOR_UNUSED;
>>
>> Is there something I didn't consider with? ;-)
> 
> Well, that just prevents the warning, but the hlist is already
> corrupted. So you'd just cure the symptom ...
> 

I see.

> I'm about to send a patch series which addresses that. Just need to finish
> writing changelogs.
> 

Thank you for telling me that.

Thanks,
	dou