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Mon, 13 Apr 2026 03:02:51 -0700 (PDT) Received: from ahossu.localdomain ([88.202.160.248]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-670702f071dsm2193723a12.4.2026.04.13.03.02.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2026 03:02:50 -0700 (PDT) Message-ID: <69dcbf4a.050a0220.1d6d81.c4df@mx.google.com> Date: Mon, 13 Apr 2026 03:02:50 -0700 (PDT) Content-Type: text/plain; charset="us-ascii" Precedence: bulk X-Mailing-List: linux-tegra@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Alexandru Hossu To: Dan Carpenter Cc: linux-tegra@vger.kernel.org, marvin24@gmx.de, gregkh@linuxfoundation.org, linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH 4/5] staging: nvec: fix pm_power_off teardown in tegra_nvec_remove() In-Reply-To: <20260412205057.386856-4-hossu.alexandru@gmail.com> References: <20260412205057.386856-4-hossu.alexandru@gmail.com> On Mon, Apr 13, 2026, Dan Carpenter wrote: > At this point, we're unloading the driver so nvec_power_handle is > about to be freed. Is there any benefit to setting it to NULL? nvec_power_off() dereferences nvec_power_handle to send the power-off command to the EC. If pm_power_off somehow gets reassigned to nvec_power_off after our driver unloads (e.g. by a re-probe), the stale nvec_power_handle would point to freed memory. Setting it to NULL makes the potential failure mode explicit rather than a silent use-after-free. Since we are already inside the if() guard, the cost is a single pointer store. Alexandru