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Date:   Mon, 3 Oct 2022 16:57:30 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc:     x86@kernel.org, "H . Peter Anvin" <hpa@zytor.com>,
        Thomas Gleixner <tglx@linutronix.de>,
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        Arnd Bergmann <arnd@arndb.de>,
        Andy Lutomirski <luto@kernel.org>,
        Balbir Singh <bsingharora@gmail.com>,
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        Cyrill Gorcunov <gorcunov@gmail.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
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Subject: Re: [PATCH v2 33/39] x86/cpufeatures: Limit shadow stack to Intel
 CPUs
Message-ID: <202210031656.23FAA3195@keescook>
References: <20220929222936.14584-1-rick.p.edgecombe@intel.com>
 <20220929222936.14584-34-rick.p.edgecombe@intel.com>
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In-Reply-To: <20220929222936.14584-34-rick.p.edgecombe@intel.com>
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On Thu, Sep 29, 2022 at 03:29:30PM -0700, Rick Edgecombe wrote:
> Shadow stack is supported on newer AMD processors, but the kernel
> implementation has not been tested on them. Prevent basic issues from
> showing up for normal users by disabling shadow stack on all CPUs except
> Intel until it has been tested. At which point the limitation should be
> removed.
> 
> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>

So running the selftests on an AMD system is sufficient to drop this
patch?

-- 
Kees Cook