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Date:   Fri, 7 Jul 2023 16:41:12 +0800
From:   Baoquan He <bhe@redhat.com>
To:     Joerg Roedel <jroedel@suse.de>
Cc:     Tao Liu <ltao@redhat.com>, thomas.lendacky@amd.com,
        Borislav Petkov <bp@alien8.de>, tglx@linutronix.de,
        mingo@redhat.com, dave.hansen@linux.intel.com, x86@kernel.org,
        hpa@zytor.com, ardb@kernel.org, linux-kernel@vger.kernel.org,
        dyoung@redhat.com, kexec@lists.infradead.org,
        linux-efi@vger.kernel.org, michael.roth@amd.com
Subject: Re: [PATCH v2] x86/kexec: Add EFI config table identity mapping for
 kexec kernel
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On 07/07/23 at 10:22am, Joerg Roedel wrote:
> On Fri, Jul 07, 2023 at 12:23:59PM +0800, Baoquan He wrote:
> > I am wondering why we don't detect the cpu type and return early inside
> > sev_enable() if it's Intel cpu.
> > 
> > We can't rely on CONFIG_AMD_MEM_ENCRYPT to decide if the code need be
> > executed or not because we usually enable them all in distros.
> 
> Looking at the code in head_64.S, by the time sev_enable() runs the SEV
> bit should already be set in sev_status. Maybe use that to detect
> whether SEV is enabled and bail out early?

Makes sense to me. Thanks.