Re: [RFC PATCH V3 03/11] x86/Hyper-V: Add new hvcall guest address host visibility support

From: Borislav Petkov
Date: Sun May 30 2021 - 14:26:28 EST


On Sun, May 30, 2021 at 11:06:20AM -0400, Tianyu Lan wrote:
> diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
> index 156cd235659f..a82975600107 100644
> --- a/arch/x86/mm/pat/set_memory.c
> +++ b/arch/x86/mm/pat/set_memory.c
> @@ -29,6 +29,8 @@
> #include <asm/proto.h>
> #include <asm/memtype.h>
> #include <asm/set_memory.h>
> +#include <asm/hyperv-tlfs.h>
> +#include <asm/mshyperv.h>
>
> #include "../mm_internal.h"
>
> @@ -1986,8 +1988,14 @@ static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc)
> int ret;
>
> /* Nothing to do if memory encryption is not active */
> - if (!mem_encrypt_active())
> + if (hv_is_isolation_supported()) {
> + return hv_set_mem_host_visibility((void *)addr,
> + numpages * HV_HYP_PAGE_SIZE,
> + enc ? VMBUS_PAGE_NOT_VISIBLE
> + : VMBUS_PAGE_VISIBLE_READ_WRITE);

Put all this gunk in a hv-specific function somewhere in hv-land which
you only call from here. This way you probably won't even need to export
hv_set_mem_host_visibility() and so on...

Thx.

--
Regards/Gruss,
Boris.

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