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([2a10:bac0:b000:7318:7285:c2ff:fedd:7e3a]) by smtp.gmail.com with ESMTPSA id x12-20020aa7d6cc000000b0056ddcbd9362sm378247edr.51.2024.04.10.23.22.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 10 Apr 2024 23:22:12 -0700 (PDT) Message-ID: <0503ff9b-afb7-43a5-b9eb-f6c9d9945638@suse.com> Date: Thu, 11 Apr 2024 09:22:10 +0300 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 2/7] x86/bugs: Cache the value of MSR_IA32_ARCH_CAPABILITIES To: Josh Poimboeuf , x86@kernel.org Cc: linux-kernel@vger.kernel.org, Linus Torvalds , Daniel Sneddon , Pawan Gupta , Thomas Gleixner , Alexandre Chartre , Konrad Rzeszutek Wilk , Peter Zijlstra , Greg Kroah-Hartman , Sean Christopherson , Andrew Cooper , Dave Hansen , KP Singh , Waiman Long , Borislav Petkov References: <9592a18a814368e75f8f4b9d74d3883aa4fd1eaf.1712813475.git.jpoimboe@kernel.org> From: Nikolay Borisov Content-Language: en-US In-Reply-To: <9592a18a814368e75f8f4b9d74d3883aa4fd1eaf.1712813475.git.jpoimboe@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 11.04.24 г. 8:40 ч., Josh Poimboeuf wrote: > There's no need to keep reading MSR_IA32_ARCH_CAPABILITIES over and > over. It's even read in the BHI sysfs function which is a big no-no. > Just read it once and cache it. > > Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") > Signed-off-by: Josh Poimboeuf Reviewed-by: Nikolay Borisov