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Peter Anvin" , Ingo Molnar , Juri Lelli , Mel Gorman , Mike Rapoport , thomas.lendacky@amd.com, Tony Luck , Vincent Guittot , x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)) Subject: [RFC 0/2] Do not slow down some AMD devices with coresched Date: Wed, 11 Nov 2020 16:10:09 -0500 Message-Id: <20201111211011.1381848-1-joel@joelfernandes.org> X-Mailer: git-send-email 2.29.2.222.g5d2a92d10f8-goog MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Here are 2 patches I am thinking of sending with next coresched series. Let me know what you think. These are for not slowing down certain AMD devices if they don't have vulnerabilities that require coresched. 1/2 - keep coresched disabled if device doesn't have vulnerability. 2/2 - add debug information. In the future, if needed we could add more options to make it possible to force-enable coresched. But right now I don't see a need for that, till a usecase arises. Joel Fernandes (Google) (2): x86/bugs: Disable coresched on hardware that does not need it sched/debug: Add debug information about whether coresched is enabled arch/x86/kernel/cpu/bugs.c | 8 ++++++++ kernel/sched/core.c | 7 +++++++ kernel/sched/debug.c | 4 ++++ kernel/sched/sched.h | 5 +++++ 4 files changed, 24 insertions(+) -- 2.29.2.222.g5d2a92d10f8-goog