From: Tom Lendacky <thomas.lendacky@amd.com>
To: Mario Limonciello <mario.limonciello@amd.com>,
Borislav Petkov <bp@alien8.de>,
"maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)"
<x86@kernel.org>
Cc: Kees Cook <keescook@chromium.org>,
hughsient@gmail.com,
Martin Fernandez <martin.fernandez@eclypsium.com>,
linux-kernel@vger.kernel.org,
Brijesh Singh <brijesh.singh@amd.com>
Subject: Re: [PATCH v4] x86/cpu: clear SME feature flag when not in use
Date: Wed, 16 Feb 2022 09:05:07 -0600 [thread overview]
Message-ID: <9fb62811-799a-0df8-2f5e-b6b6990d26e3@amd.com> (raw)
In-Reply-To: <20220216034446.2430634-1-mario.limonciello@amd.com>
On 2/15/22 21:44, Mario Limonciello wrote:
> Currently the SME CPU feature flag is reflective of whether the CPU
> supports the feature but not whether is has been activated by the
> kernel.
>
> Change this around to clear the SME feature flag if the kernel is not
> using it so userspace can determine if it is available and in use
> from `/proc/cpuinfo`.
>
> As the feature flag is cleared on systems where SME isn't active use
> CPUID 0x8000001f to confirm SME availability before calling
> `native_wbinvd`.
>
> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
> ---
next prev parent reply other threads:[~2022-02-16 15:05 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-16 3:44 [PATCH v4] x86/cpu: clear SME feature flag when not in use Mario Limonciello
2022-02-16 10:33 ` Borislav Petkov
2022-02-16 13:41 ` Limonciello, Mario
2022-02-16 15:05 ` Tom Lendacky [this message]
2022-02-16 20:16 ` [tip: x86/cpu] x86/cpu: Clear " tip-bot2 for Mario Limonciello
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=9fb62811-799a-0df8-2f5e-b6b6990d26e3@amd.com \
--to=thomas.lendacky@amd.com \
--cc=bp@alien8.de \
--cc=brijesh.singh@amd.com \
--cc=hughsient@gmail.com \
--cc=keescook@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mario.limonciello@amd.com \
--cc=martin.fernandez@eclypsium.com \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.