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[82.69.66.36]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4801e8d90b3sm309257495e9.15.2026.01.21.02.59.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 21 Jan 2026 02:59:29 -0800 (PST) Date: Wed, 21 Jan 2026 10:59:28 +0000 From: David Laight To: Borislav Petkov Cc: "H. Peter Anvin" , David Desobry , tglx@kernel.org, mingo@redhat.com, dave.hansen@linux.intel.com, x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] x86/lib: Fix num_digits() signed overflow for INT_MIN Message-ID: <20260121105928.21c5e2de@pumpkin> In-Reply-To: <20260120201346.GEaW_h-tUO2pb4d26w@fat_crate.local> References: <20260120094258.41313-1-david.desobry@formalgen.com> <53DB5B87-BA96-44B1-AE1B-9055CB7B9350@zytor.com> <20260120164050.GBaW-wEvzp9WVFj9n9@fat_crate.local> <7C458D74-49E8-4FFE-BD60-74CA3ABFDC6C@zytor.com> <20260120191655.GDaW_Up2ZOv5AHhbq7@fat_crate.local> <20260120201346.GEaW_h-tUO2pb4d26w@fat_crate.local> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; arm-unknown-linux-gnueabihf) Precedence: bulk X-Mailing-List: linux-kernel@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 Tue, 20 Jan 2026 21:13:46 +0100 Borislav Petkov wrote: > On Tue, Jan 20, 2026 at 11:50:41AM -0800, H. Peter Anvin wrote: > > For negative numbers? Dave Hansen pointed out that we currently don't ever > > pass negative numbers, in which case it would make more sense to have the > > function simply take an unsigned int. > > Yes, that's why I'm asking what we're even fixing here... You can certainly just document it doesn't work for INT_MIN. David