On 29.04.2020 13:32, Andrew Cooper wrote:
> On 29/04/2020 12:16, Jan Beulich wrote:
>> On 29.04.2020 13:09, Andrew Cooper wrote:
>>> --- a/xen/arch/x86/boot/trampoline.S
>>> +++ b/xen/arch/x86/boot/trampoline.S
>>> @@ -91,6 +91,11 @@ trampoline_protmode_entry:
>>> and %edi,%edx
>>> wrmsr
>>> 1:
>>> + /* Set up PAT before enabling paging. */
>>> + mov $XEN_MSR_PAT & 0xffffffff, %eax
>>> + mov $XEN_MSR_PAT >> 32, %edx
>>> + mov $MSR_IA32_CR_PAT, %ecx
>>> + wrmsr
>> Doesn't this also eliminate the need for cpu_init() doing this?
>> If you agree with that one also dropped
>> Reviewed-by: Jan Beulich <jbeul...@suse.com>
>
> That doesn't cover the BSP on either the legacy or EFI paths.
The legacy path, afaict, uses it:
.Lskip_realmode:
/* EBX == 0 indicates we are the BP (Boot Processor). */
xor %ebx,%ebx
/* Jump to the common bootstrap entry point. */
jmp trampoline_protmode_entry
The xen.efi entry path really should have the change you make
mirrored anyway.
Jan
