On 2/23/23 12:26, Dave Hansen wrote:
>> + if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) {
>> + /*
>> + * Ensure fixmaps for IOAPIC MMIO respect memory encryption pgprot
>> + * bits, just like normal ioremap():
>> + */
>> + if (x86_platform.hyper.is_private_mmio(phys))
>> + flags = pgprot_encrypted(flags);
>> + else
>> + flags = pgprot_decrypted(flags);
>> + }
...
> It does seem a bit odd that there's a new CC_ATTR_GUEST_MEM_ENCRYPT
> check wrapping this whole thing. I guess the trip through
> pgprot_decrypted() is harmless on normal platforms, though.
Yeah, that's _really_ odd. Sean, were you trying to optimize away the
indirect call or something?
I would just expect the Hyper-V/vTOM code to leave
x86_platform.hyper.is_private_mmio alone unless
it *knows* the platform has private MMIO *and* CC_ATTR_GUEST_MEM_ENCRYPT.
Is there ever a case where CC_ATTR_GUEST_MEM_ENCRYPT==0 and he
Hyper-V/vTOM code would need to set x86_platform.hyper.is_private_mmio?
