[PATCH V4] POWERPC: BOOK3S: KVM: Use the saved dar value and generic make_dsisr

Aneesh Kumar K.V aneesh.kumar at linux.vnet.ibm.com
Wed May 7 00:12:28 EST 2014

Alexander Graf <agraf at suse.de> writes:

> On 06.05.14 02:41, Paul Mackerras wrote:
>> On Mon, May 05, 2014 at 01:19:30PM +0200, Alexander Graf wrote:
>>> On 05/04/2014 07:21 PM, Aneesh Kumar K.V wrote:
>>>> +#ifdef CONFIG_PPC_BOOK3S_64
>>>> +	return vcpu->arch.fault_dar;
>>> How about PA6T and G5s?
>> G5 sets DAR on an alignment interrupt.
>> As for PA6T, I don't know for sure, but if it doesn't, ordinary
>> alignment interrupts wouldn't be handled properly, since the code in
>> arch/powerpc/kernel/align.c assumes DAR contains the address being
>> accessed on all PowerPC CPUs.
> Now that's a good point. If we simply behave like Linux, I'm fine. This 
> definitely deserves a comment on the #ifdef in the code.

How about ?

	 * Linux always expect a valid  dar as per alignment
	 * interrupt handling code (fix_alignment()). Don't compute the dar
	 * value here, instead used the saved dar value. Right now we restrict
	 * this only for BOOK3S-64.
	return vcpu->arch.fault_dar;


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