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From:   Paul Menzel <pmenzel@molgen.mpg.de>
To:     Tom Lendacky <thomas.lendacky@amd.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        x86@kernel.org
Cc:     Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        amd-gfx@lists.freedesktop.org
Subject: `AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT=y` causes AMDGPU to fail on Ryzen:
 amdgpu: SME is not compatible with RAVEN
Message-ID: <8bbacd0e-4580-3194-19d2-a0ecad7df09c@molgen.mpg.de>
Date:   Tue, 5 Oct 2021 16:29:41 +0200
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Dear Tom, dear Linux folks,


Selecting the symbol `AMD_MEM_ENCRYPT` – as done in Debian 5.13.9-1~exp1 
[1] – also selects `AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT`, as it defaults 
to yes, causing boot failures on AMD Raven systems. On the MSI B350M 
MORTAR with AMD Ryzen 3 2200G, Linux logs and the AMDGPU graphics 
driver, despite being loaded, does not work, and the framebuffer driver 
is used instead.

     [   19.679824] amdgpu 0000:26:00.0: amdgpu: SME is not compatible 
with RAVEN

It even causes black screens on other systems as reported to the Debian 
bug tracking system *Black screen on AMD Ryzen based systems (AMDGPU 
related when AMD Secure Memory Encryption not disabled -- 
mem_encrypt=off)* [2].

Should the default be changed?


Kind regards,

Paul


[1]: 
https://salsa.debian.org/kernel-team/linux/-/blob/master/debian/changelog#L1138
[2]: https://bugs.debian.org/994453