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[92.21.58.28]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4538a3b2fd7sm129422525e9.17.2025.06.30.01.30.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 30 Jun 2025 01:30:39 -0700 (PDT) Date: Mon, 30 Jun 2025 09:30:27 +0100 From: David Laight To: "Kirill A. Shutemov" Cc: Xin Li , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Peter Zijlstra , Ard Biesheuvel , "Paul E. McKenney" , Josh Poimboeuf , Xiongwei Song , Xin Li , "Mike Rapoport (IBM)" , Brijesh Singh , Michael Roth , Tony Luck , Alexey Kardashevskiy , Alexander Shishkin , Jonathan Corbet , Sohil Mehta , Ingo Molnar , Pawan Gupta , Daniel Sneddon , Kai Huang , Sandipan Das , Breno Leitao , Rick Edgecombe , Alexei Starovoitov , Hou Tao , Juergen Gross , Vegard Nossum , Kees Cook , Eric Biggers , Jason Gunthorpe , "Masami Hiramatsu (Google)" , Andrew Morton , Luis Chamberlain , Yuntao Wang , Rasmus Villemoes , Christophe Leroy , Tejun Heo , Changbin Du , Huang Shijie , Geert Uytterhoeven , Namhyung Kim , Arnaldo Carvalho de Melo , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCHv7 13/16] x86/traps: Handle LASS thrown #SS Message-ID: <20250630093027.38cd1ebc@pumpkin> In-Reply-To: References: <20250625125112.3943745-1-kirill.shutemov@linux.intel.com> <20250625125112.3943745-15-kirill.shutemov@linux.intel.com> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; arm-unknown-linux-gnueabihf) Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Fri, 27 Jun 2025 13:31:44 +0300 "Kirill A. Shutemov" wrote: > On Thu, Jun 26, 2025 at 10:57:47AM -0700, Xin Li wrote: > > On 6/25/2025 5:51 AM, Kirill A. Shutemov wrote: > > > LASS throws a #GP for any violations except for stack register accesses, > > > in which case it throws a #SS instead. Handle this similarly to how other > > > LASS violations are handled. > > > > > > In case of FRED, before handling #SS as LASS violation, kernel has to > > > check if there's a fixup for the exception. It can address #SS due to > > > invalid user context on ERETU[1]. See 5105e7687ad3 ("x86/fred: Fixup > > > > Forgot to put the link to [1]? Maybe just remove "[1]"? > > I will add the link. It is important context. Will the link still be valid in 5 years time when someone is looking back at the changes? David