[PATCH] powerpc64/hw_breakpoints: Handle data breakpoints in radix mode

[Naveen N. Rao]

On 2017/06/14 04:41PM, Michael Ellerman wrote:
> "Aneesh Kumar K.V" <aneesh.kumar at linux.vnet.ibm.com> writes:
> > On Wednesday 14 June 2017 10:41 AM, Naveen N. Rao wrote:
> >> On 2017/06/14 08:38AM, Aneesh Kumar K.V wrote:
> >>> "Naveen N. Rao" <naveen.n.rao at linux.vnet.ibm.com> writes:
> >>>> diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
> >>>> index ae418b85c17c..17ee701b8336 100644
> >>>> --- a/arch/powerpc/kernel/exceptions-64s.S
> >>>> +++ b/arch/powerpc/kernel/exceptions-64s.S
> >>>> @@ -1411,10 +1411,8 @@ USE_TEXT_SECTION()
> >>>>   	.balign	IFETCH_ALIGN_BYTES
> >>>>   do_hash_page:
> >>>>   #ifdef CONFIG_PPC_STD_MMU_64
> >>>> -	andis.	r0,r4,0xa410		/* weird error? */
> >>>> +	andis.	r0,r4,0xa450		/* weird error? */
> >>>
> >>> Can we convert that to a #define value. Ram did try to do that here.
> >>>
> >>> https://lists.ozlabs.org/pipermail/linuxppc-dev/2017-June/158607.html
> >> 
> >> Hmm... I feel it will be good to do that as part of Ram's series since
> >> he has already coded it up :)
> >> 
> >> Ram's patches will anyway require a rebase and the change I do here for
> >> detecting DAWR already has a #define, so it should be a simple matter of
> >> including DSISR_DABRMATCH in DSISR_PAGE_FAULT_MASK.
> >> 
> >> But, if you really feel that I should make that change here, please do
> >> let me know and I will re-spin with those changes.
> >
> > The thing is that change from 0xa410 to 0xa450 is not clear at all. And 
> > it needs proper documentation. IMHO the best way to do that is switch to 
> > #define name for that constant.
> 
> Not in this patch. It needs to be backported, so it should be as minimal
> as possible.

Ok.

> 
> The change from 0xa410 to 0xa450 does need a mention in the changelog,
> I'll add that.

Thanks, Michael!
(emails just started flowing again...)

- Naveen