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bh=5JyAU/JLXXFTtWRREUsOU6epWY/XYVNcnOAGJNFiKwQ=; b=KfT0Mprsz3GxEPCAHwdg1TWJdHhDGdprVbR1LinIpkwcnWj7jDEX1DKTHH+u78Piqgl1Hx amVRkuP4FWCjAxkPyivEHudk+yPMYUX/52dgOi4wIoog5yCgYHAU80iTBlhSGQ7LLjjQlA wL++YKYAZeBiZt7LZf4JQ7+tBM7fhtY= Date: Sat, 4 Feb 2023 11:37:58 +0100 From: Borislav Petkov To: "Edgecombe, Rick P" Cc: "bsingharora@gmail.com" , "hpa@zytor.com" , "Syromiatnikov, Eugene" , "peterz@infradead.org" , "rdunlap@infradead.org" , "keescook@chromium.org" , "Yu, Yu-cheng" , "Eranian, Stephane" , "kirill.shutemov@linux.intel.com" , "dave.hansen@linux.intel.com" , "linux-mm@kvack.org" , "fweimer@redhat.com" , "nadav.amit@gmail.com" , "jannh@google.com" , "dethoma@microsoft.com" , "kcc@google.com" , "linux-arch@vger.kernel.org" , "pavel@ucw.cz" , "oleg@redhat.com" , "hjl.tools@gmail.com" , "Yang, Weijiang" , "Lutomirski, Andy" , "jamorris@linux.microsoft.com" , "arnd@arndb.de" , "tglx@linutronix.de" , "Schimpe, Christina" , "mike.kravetz@oracle.com" , "x86@kernel.org" , "akpm@linux-foundation.org" , "andrew.cooper3@citrix.com" , "john.allen@amd.com" , "linux-doc@vger.kernel.org" , "rppt@kernel.org" , "mingo@redhat.com" , "mtk.manpages@gmail.com" , "corbet@lwn.net" , "linux-kernel@vger.kernel.org" , "linux-api@vger.kernel.org" , "gorcunov@gmail.com" Subject: Re: [PATCH v5 07/39] x86: Add user control-protection fault handler Message-ID: References: <20230119212317.8324-1-rick.p.edgecombe@intel.com> <20230119212317.8324-8-rick.p.edgecombe@intel.com> <393a03d063dee5831af93ca67636df75a76481c3.camel@intel.com> <828f1b3154227c06ac1787961016464a4c116cc2.camel@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <828f1b3154227c06ac1787961016464a4c116cc2.camel@intel.com> X-Rspamd-Queue-Id: 750188000E X-Rspamd-Server: rspam09 X-Rspam-User: X-Stat-Signature: 3b7xuz38sfmnn47jxgc8tgq8c8w95spd X-HE-Tag: 1675507085-781939 X-HE-Meta: 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 OAWWBysh 5EWiYQllRh55FQVmfYHVidPYDlDulffNzolAW04o8QHe1u+3Q6Pct6omlSkBJV6INZ6Ny5JFNG5SmUnPP7RFjpQoq+1We9sDk8P6WRrMM7/73m67+qjfPT9pnLlvi97emFxiXKknrQqrknoKnHS64U/DnkMEiW/A8OAvto4/mEyWGTFsyhUAwfAiS/YvI3PZc1rJ7ptTrUK4DkK9RPbVbNLrvQD48q0ETgvqjdK+I3qHAGFhL1Xic1GxdU9frljRUh4rfg4+H6W6PC6KqSSs2V1P+jZRNFNqPtZa55EQwHaVGC2Lv81xh106gblUDrqDhLMUJyeDOFhD6/fo= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Feb 03, 2023 at 11:01:42PM +0000, Edgecombe, Rick P wrote: > Since this path is only for exceptions coming from userspace, I think > it should be valid either way. It can't be during a task switch. > I can swap the lines if it looks odd, but unless I'm wrong about the > 'current' validity I think it's negligibly better as is because it is > preemptible for as long as possible. Nah, all good. I was confused here. Sorry for the noise. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette