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Date:   Sun, 30 May 2021 20:25:47 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Tianyu Lan <ltykernel@gmail.com>
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Subject: Re: [RFC PATCH V3 03/11] x86/Hyper-V: Add new hvcall guest address
 host visibility support
Message-ID: <YLPYqxF7urDIAd9z@zn.tnic>
References: <20210530150628.2063957-1-ltykernel@gmail.com>
 <20210530150628.2063957-4-ltykernel@gmail.com>
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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.

https://people.kernel.org/tglx/notes-about-netiquette