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Subject: Re: powerpc/book3s: Fix flush_tlb cpu_spec hook to take a generic
 argument.
From: Michael Ellerman <mpe@ellerman.id.au>
To: Mahesh Jagannath Salgaonkar <mahesh@linux.vnet.ibm.com>
Date: Thu, 04 Dec 2014 20:35:53 +1100
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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 <mahesh@linux.vnet.ibm.com>
> >>
> >> 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.

cheers