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Wed, 28 Oct 2026 12:23:33 -0700 (PDT) Received: from thinkpad ([2a00:1370:81ac:50e7:d3c8:c903:5898:874a]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-48e3ecdd5b3sm29978125f8f.53.2026.10.28.12.23.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 28 Oct 2026 12:23:33 -0700 (PDT) From: s1nkhole To: dave.hansen@intel.com Cc: x86@kernel.org, Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , hpa@zytor.com, Peter Zijlstra , Kees Cook , Brian Gerst , Pawan Gupta , linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Andrey Zakharov Subject: Re: [PATCH] x86/entry/32: Harden return-to-user Date: Wed, 28 Oct 2026 22:21:39 +0300 Message-ID: <20261028192139.32606-1-dedemorow@gmail.com> X-Mailer: git-send-email 2.56.0 In-Reply-To: References: X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Andrey Zakharov On 10/27/26 15:01, Dave Hansen wrote: > I'm curious who cares. > > Is anyone who is actually still running a 32-bit kernel concerned about > this kind of hardening? > > If no one cares, then I'd rather pass on the complexity, even four > instructions of it. I don't know of anyone. The only motivation was KSPP issue #41, which asks for parity with the x86-64 check added by 1e4d3001f59f, and that issue is marked as low priority because 32-bit is legacy. I have no report from a 32-bit user asking for it. Please drop the patch. Thanks for looking at it. If you have a moment: this is my first work on arch/x86, and I would like to contribute something that is actually useful. Is there a small task in x86/entry or in kernel hardening that you would suggest as a better starting point, or a place where help with testing or review would be welcome? I can build and run kernels under QEMU. Thanks, Andrey Zakharov