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Re: [Xen-devel] [RFC] x86: possible problem with guest_walk_tables()

>>> On 21.03.11 at 15:50, Tim Deegan <Tim.Deegan@xxxxxxxxxx> wrote:
> At 14:19 +0000 on 21 Mar (1300717156), Jan Beulich wrote:
>> >> Leaving aside the non-PAE case, does the fix presented look
>> >> reasonable?
>> >  
>> > Yes, it looks correct to me.  Give me a Signed-off-by and I'll apply it. 
>> Going with the page-fault-less case then for non-PAE? If we want
>> that case to produce reserved bit faults too, I admit I'd prefer to
>> submit a complete patch (which is half the reason why this was an
>> RFC, non-signed-off one)... If we want no fault there, I'd like to
>> comment that way in the code (so the or-ing with zero won't
>> prompt later readers to wonder whether this isn't a bug/oversight).
> OK, I'll wait until I can fix up the non-PAE case too.

Jun points out that SDM tables 5-8 and 5-9 are pretty complete.
According to them, only bit 21 set would cause a reserved bit
fault. Which fits pretty badly into the present code, hence I'm
not certain it's worth to uglify the code just for this case. I'll
therefore submit the patch with just a comment added for now -
later adjustments can still be done if desired.


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