Does qemu support "invlpg" instruction?

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venuswu
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Does qemu support "invlpg" instruction?

Post by venuswu »

Does qemu support "invlpg" instruction?
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Combuster
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Re: Does qemu support "invlpg" instruction?

Post by Combuster »

Have you tried?


What CPUs support INVLPG? What CPU does qemu pretend to be?
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iansjack
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Re: Does qemu support "invlpg" instruction?

Post by iansjack »

Yes, it is supported.
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Re: Does qemu support "invlpg" instruction?

Post by Combuster »

Learning opportunity spoilt :(
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Re: Does qemu support "invlpg" instruction?

Post by OSwhatever »

Does invlpg do anything in qemu or is it bascially a nop?
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iansjack
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Re: Does qemu support "invlpg" instruction?

Post by iansjack »

"Learning opportunity spoilt"

Yes, but it's not immediately obvious whether this particular instruction is working correctly. I assume that the OP has a problem with it in qemu and will now come back with the real question.
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Re: Does qemu support "invlpg" instruction?

Post by iansjack »

OSwhatever wrote:Does invlpg do anything in qemu or is it bascially a nop?
It would be a bit pointless if it did nothing, wouldn't it?
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Re: Does qemu support "invlpg" instruction?

Post by Brendan »

Hi,
iansjack wrote:
OSwhatever wrote:Does invlpg do anything in qemu or is it bascially a nop?
It would be a bit pointless if it did nothing, wouldn't it?
For Qemu, how many entries does CPUID say the TLB holds?

If a CPU has "0 TLB entries", then what should INVLPG do? ;)


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Brendan
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