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[82.37.195.13]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-43569921da2sm23988345f8f.1.2026.01.19.08.15.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 Jan 2026 08:15:27 -0800 (PST) Date: Mon, 19 Jan 2026 16:15:25 +0000 From: Daniel Thompson To: Markus Elfring Cc: linux-trace-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Masami Hiramatsu , Mathieu Desnoyers , Steven Rostedt , LKML , Robin Murphy , Will Deacon Subject: Re: iommu: Fix NULL pointer deref when io_page_fault tracepoint fires Message-ID: References: <20260116-iommu-io_page_fault_null_fix-v1-1-6c20c2e62987@riscstar.com> 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=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Mon, Jan 19, 2026 at 04:56:04PM +0100, Markus Elfring wrote: > >> … > >>> Fix this by adding logic to the tracepoint to safely propagate NULL. > >> > >> * How do you think about to add any tags (like “Fixes” and “Cc”) accordingly? > > > > I could add a > > > > Fixes: f8f934c180f6 ("iommu/arm-smmu: Add support for driver IOMMU fault handlers") > > > > However, who do you think I neglected to Cc:? > > See also once more: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?h=v6.19-rc5#n262 > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/stable-kernel-rules.rst?h=v6.19-rc5#n34 That's not what I asked! You suggested I add people to Cc:, who do you think I missed? > >> * Would a summary phrase like “Prevent null pointer dereference for a tracepoint” > >> be a bit nicer? > > > > I don't understand what is wrong with the original phrasing. Can you > > explain why this change matters to you? > > * Questionable abbreviation “deref” > * when clause I dislike the proposed new summary. I think keeping "io_page_fault" in the summary is a much better use of characters than spelling dereference in full. Daniel.