Subject: Re: powerpc/book3s: Fix flush_tlb cpu_spec hook to take a generic argument.

From: Mahesh Jagannath Salgaonkar <[email-masked]>
Date: Fri, 05 Dec 2014 10:03:56 +0530

On 12/04/2014 03:05 PM, Michael Ellerman wrote:
> On Tue, 2014-12-02 at 14:31 +0530, Mahesh Jagannath Salgaonkar wrote:
>> On 11/29/2014 04:08 AM, Michael Ellerman wrote:
>>> On Tue, 2014-23-09 at 03:53:54 UTC, Mahesh Salgaonkar wrote:
>>>> From: Mahesh Salgaonkar <[email-masked]>
>>>>
>>>> The flush_tlb hook in cpu_spec was introduced as a generic function hook
>>>> to invalidate TLBs. But the current implementation of flush_tlb hook
>>>> takes IS (invalidation selector) as an argument which is architecture
>>>> dependent. Hence, It is not right to have a generic routine where caller
>>>> has to pass non-generic argument.
>>>>
>>>> This patch fixes this and makes flush_tlb hook as high level API.
>>>>
>>>> The old code used to call flush_tlb hook with IS=0 (single page) resulting
>>>> partial invalidation of TLBs which is not right. This fix now makes
>>>> sure that whole TLB is invalidated to be able to successfully recover from
>>>> TLB and ERAT errors.
>>>
>>> Which old code? You mean the MCE code I think. That's a bug fix, so it should
>>> be a separate patch.
>>
>> Yes. MCE code. Since this patch re-factors the code that takes IS as
>> direct argument, having a separate fix patch does not make any sense and
>> would get overwritten by this patch anyway.
> 
> That's irrelevant.
> 
> The fix will go to stable, the refactor will not.
> 
> Please do the MCE fix as a separate, preceeding patch.

Done. Sent out a separate fix patch for stable
https://lists.ozlabs.org/pipermail/linuxppc-dev/2014-December/123310.html

Thanks,
-Mahesh.