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charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <608f95249ff3a39efb063ab9c6a543259a7b0ac9.camel@collabora.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250609_024258_733097_0B5B183F X-CRM114-Status: GOOD ( 16.69 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi, On Thu, Jun 05, 2025 at 08:41:45AM -0400, Nicolas Dufresne wrote: > Hi Hans, Sakari, > > Le jeudi 05 juin 2025 à 09:48 +0000, Sakari Ailus a écrit : > > > It's not user-triggerable, if this happens, then it is a driver bug. > > > > If there is a driver bug, it could well be user-triggerable, wouldn't it? > > Testing may not uncover all such cases. > > You are both right, if the driver is not used, the warning will never > trigger. I was worried of the hit of a thread safe ONCE implementation, > but WARN_ONCE is simply not, it can warn few time before it stops if > called from multiple CPUs at the same time. In that specific function, > I can move all the checks inside the lock to make it truly once. > > Now its up to you, I don't have strong preference. These are driver errors, > and usually quite critical. They are not bug_on simply because we have a > crash free resolution, but its probably not functional anymore. I'd prefer _ONCE variants, I wonder what Hans thinks. -- Regards, Sakari Ailus