Date:   Tue, 31 Jan 2023 14:03:36 +0000
From:   Wei Liu <wei.liu@kernel.org>
To:     Tianyu Lan <ltykernel@gmail.com>
Cc:     luto@kernel.org, tglx@linutronix.de, mingo@redhat.com,
        bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org,
        hpa@zytor.com, seanjc@google.com, pbonzini@redhat.com,
        jgross@suse.com, tiala@microsoft.com, kirill@shutemov.name,
        jiangshan.ljs@antgroup.com, peterz@infradead.org,
        ashish.kalra@amd.com, srutherford@google.com,
        akpm@linux-foundation.org, anshuman.khandual@arm.com,
        pawan.kumar.gupta@linux.intel.com, adrian.hunter@intel.com,
        daniel.sneddon@linux.intel.com, alexander.shishkin@linux.intel.com,
        sandipan.das@amd.com, ray.huang@amd.com, brijesh.singh@amd.com,
        michael.roth@amd.com, thomas.lendacky@amd.com,
        venu.busireddy@oracle.com, sterritt@google.com,
        tony.luck@intel.com, samitolvanen@google.com, fenghua.yu@intel.com,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        linux-hyperv@vger.kernel.org, linux-arch@vger.kernel.org,
        Wei Liu <wei.liu@kernel.org>
Subject: Re: [RFC PATCH V3 09/16] x86/hyperv: SEV-SNP enlightened guest don't
 support legacy rtc
Message-ID: <Y9kfuFGVoIlOfnoK@liuwe-devbox-debian-v2>
References: <20230122024607.788454-1-ltykernel@gmail.com>
 <20230122024607.788454-10-ltykernel@gmail.com>
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On Sat, Jan 21, 2023 at 09:45:59PM -0500, Tianyu Lan wrote:
> From: Tianyu Lan <tiala@microsoft.com>
> 
> SEV-SNP enlightened guest doesn't support legacy rtc. Set
> legacy.rtc, x86_platform.set_wallclock and get_wallclock to
> 0 or noop(). Make get/set_rtc_noop() to be public and reuse
> them in the ms_hyperv_init_platform().
> 
> Signed-off-by: Tianyu Lan <tiala@microsoft.com>
> ---
>  arch/x86/include/asm/mshyperv.h | 7 ++++++-
>  arch/x86/include/asm/x86_init.h | 2 ++
>  arch/x86/kernel/cpu/mshyperv.c  | 3 +++
>  arch/x86/kernel/x86_init.c      | 4 ++--
>  4 files changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
> index 1a4af0a4f29a..7266d71d30d6 100644
> --- a/arch/x86/include/asm/mshyperv.h
> +++ b/arch/x86/include/asm/mshyperv.h
> @@ -33,6 +33,12 @@ extern bool hv_isolation_type_en_snp(void);
>  
>  extern union hv_ghcb * __percpu *hv_ghcb_pg;
>  
> +/*
> + * Hyper-V puts processor and memory layout info
> + * to this address in SEV-SNP enlightened guest.
> + */
> +#define EN_SEV_SNP_PROCESSOR_INFO_ADDR	0x802000

This hunk should be moved to the previous patch. It is not needed in
this patch.

Thanks,
Wei.