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Wed, 11 Jun 2025 09:12:08 -0700 (PDT) From: Alex Guo To: geert@linux-m68k.org Cc: alexguo1023@gmail.com, deller@gmx.de, dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] fbdev: pm3fb: Fix potential divide by zero Date: Wed, 11 Jun 2025 12:12:07 -0400 Message-Id: <20250611161207.4031677-1-alexguo1023@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi Greet, Thanks for your confirmation and suggestions. I added this patch based on existing checks on var->pixclock in other drivers, such as savagefb_check_var, nvidiafb_check_var, etc. Are you suggesting that it is better to replace an invalid value (var->pixclock == 0) with a default valid value, instead of returning -EINVAL? If so, could you advise what a suitable default value would be for this case? Actually, I have found a few similar issues in other functions as well. I would like to make sure I am addressing them in the correct way. Best, Alex