Re: [PATCH v7 5/9] powerpc/pseries: flush SLB contents on SLB MCE errors.

[Mahesh Jagannath Salgaonkar <mahesh@linux.vnet.ibm.com>]

On 08/08/2018 02:34 PM, Nicholas Piggin wrote:
> On Tue, 07 Aug 2018 19:47:14 +0530
> Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com> wrote:
> 
>> From: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
>>
>> On pseries, as of today system crashes if we get a machine check
>> exceptions due to SLB errors. These are soft errors and can be fixed by
>> flushing the SLBs so the kernel can continue to function instead of
>> system crash. We do this in real mode before turning on MMU. Otherwise
>> we would run into nested machine checks. This patch now fetches the
>> rtas error log in real mode and flushes the SLBs on SLB errors.
>>
>> Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
>> Signed-off-by: Michal Suchanek <msuchanek@suse.com>
>> ---
>>
>> Changes in V7:
>> - Fold Michal's patch into this patch.
>> - Handle MSR_RI=0 and evil context case in MC handler.
>> ---
> 
> 
>> diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
>> index cb796724a6fc..e89f675f1b5e 100644
>> --- a/arch/powerpc/mm/slb.c
>> +++ b/arch/powerpc/mm/slb.c
>> @@ -145,6 +145,12 @@ void slb_flush_and_rebolt(void)
>>  	get_paca()->slb_cache_ptr = 0;
>>  }
>>  
>> +void slb_flush_and_rebolt_realmode(void)
>> +{
>> +	__slb_flush_and_rebolt();
>> +	get_paca()->slb_cache_ptr = 0;
>> +}
>> +
>>  void slb_vmalloc_update(void)
>>  {
>>  	unsigned long vflags;
> 
> Can you use this patch for the SLB flush?
> 
> https://patchwork.ozlabs.org/patch/953034/

Will use your v2.

Thanks,
-Mahesh.

> 
> Thanks,
> Nick
>