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Date:   Sun, 12 Nov 2023 13:45:35 -0500
From:   Sasha Levin <sashal@kernel.org>
To:     Adam Dunlap <acdunlap@google.com>
Cc:     stable@vger.kernel.org, Peter Gonda <pgonda@google.com>,
        Jacob Xu <jacobhxu@google.com>,
        Dave Hansen <dave.hansen@linux.intel.com>
Subject: Re: Backport f79936545fb12 ("x86/sev-es: Allow
 copy_from_kernel_nofault() in earlier boot")
Message-ID: <ZVEdT6MwMH2ElB_f@sashalap>
References: <CAMBK9=YqXa11BUPBLnitvHRFYGdEX=J3S1ssq=iBWRYpGCynBA@mail.gmail.com>
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On Fri, Nov 10, 2023 at 09:05:19AM -0800, Adam Dunlap wrote:
>commit f79936545fb122856bd78b189d3c7ee59928c751 upstream.
>
>This patch fixes a boot failure that happens with VMs running with
>SEV-ES or SEV-SNP when the guest kernel is compiled with a gcc version
>past 12.3 (or possibly earlier) due to undefined behavior. As far as I
>know, the UB has existed ever since SEV-ES guest support was merged in
>(I believe 5.9), but only started causing boot failures with the
>updated compiler. Thus, I propose backporting this patch to stable
>branches since 5.9.

Looks like its already queued for 5.15+, and needed some minor massaging
to get to 5.10.

-- 
Thanks,
Sasha