linux-kernel - Re: [PATCH V6 2/5] x86/hyper-v: Add hyperv Isolation VM check in the cc_platform

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 7 Dec 2021 10:47:01 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     Tianyu Lan <ltykernel@...il.com>
Cc:     kys@...rosoft.com, haiyangz@...rosoft.com, sthemmin@...rosoft.com,
        wei.liu@...nel.org, decui@...rosoft.com, tglx@...utronix.de,
        mingo@...hat.com, dave.hansen@...ux.intel.com, x86@...nel.org,
        hpa@...or.com, davem@...emloft.net, kuba@...nel.org,
        jejb@...ux.ibm.com, martin.petersen@...cle.com, arnd@...db.de,
        hch@...radead.org, m.szyprowski@...sung.com, robin.murphy@....com,
        Tianyu.Lan@...rosoft.com, thomas.lendacky@....com,
        michael.h.kelley@...rosoft.com, iommu@...ts.linux-foundation.org,
        linux-arch@...r.kernel.org, linux-hyperv@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-scsi@...r.kernel.org,
        netdev@...r.kernel.org, vkuznets@...hat.com, brijesh.singh@....com,
        konrad.wilk@...cle.com, hch@....de, joro@...tes.org,
        parri.andrea@...il.com, dave.hansen@...el.com
Subject: Re: [PATCH V6 2/5] x86/hyper-v: Add hyperv Isolation VM check in the
 cc_platform_has()

On Tue, Dec 07, 2021 at 02:55:58AM -0500, Tianyu Lan wrote:
> From: Tianyu Lan <Tianyu.Lan@...rosoft.com>
> 
> Hyper-V provides Isolation VM which has memory encrypt support. Add
> hyperv_cc_platform_has() and return true for check of GUEST_MEM_ENCRYPT
> attribute.

You need to refresh on how to write commit messages - never say what the
patch is doing - that's visible in the diff itself. Rather, you should
talk about *why* it is doing what it is doing.

>  bool cc_platform_has(enum cc_attr attr)
>  {
> +	if (hv_is_isolation_supported())
> +		return hyperv_cc_platform_has(attr);

Is there any reason for the hv_is_.. check to come before...

> +
>  	if (sme_me_mask)
>  		return amd_cc_platform_has(attr);

... the sme_me_mask check?

What's in sme_me_mask on hyperv?

Thx.

-- 
Regards/Gruss,
    Boris.

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