From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 096603A759A; Tue, 28 Apr 2026 09:32:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777368749; cv=none; b=jj9D1ZmGbNsHsopEtMhAkVY5UL6CvZV/r3pePehKeGyAb/TktYb01v4IZTbNoxn81VzcjfbCg/UNwak9Ekv0w+jS4PGhOEmNTAYC8+ukWAaemc41oft3tDKgsGgziRBgUPqTJP+5KIvGksCerITevE0pr9o40bDA1dnEvS5veLc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777368749; c=relaxed/simple; bh=fSNGOPBGa0A0LSj6PeTlCNVS7DnLh6qenN2QOZYXnKQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=bS97iFcQ3YcdDcfQsiZIz6SF0mQT7yd49jImiQ7wpZAX70np9gVUMyX5p8crhZlpLNNibKxBkuqdBOkVwUxNFdjS6o7m99gmCHgb4WiaR9HFA/50XDtXFnW4mQ3AWMDxsnSp+EP0vdbgMKxk/D8JqHTullzlgao6tLFH5KrUcFw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=lKdqO6YE; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="lKdqO6YE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4957EC2BCAF; Tue, 28 Apr 2026 09:32:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777368748; bh=fSNGOPBGa0A0LSj6PeTlCNVS7DnLh6qenN2QOZYXnKQ=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=lKdqO6YEw6QozffP+yWzUbIzB65pJLXLFpvxDDx2FFlj0NEvYrdhcRZXz+Mklg8IJ iVrs4r+bWXbZYQc6zkREHs264XdXRIP0hyms/qE3q1npYXXyswaMlAwzfR7REOow5P ufrs133aq8IZhS19VrQJ7t3HfTgle5R/ECXEz2cDgL5XACMoT0PnV9Mi+5h5hlYQ0D 0RI5nZs/UJgZ4/JCeSntsWfU8+jMdfKtJgh3DB3ro4ByFr+dnN8hcaEfsrstnYufxH LuGscfvgUgGRtoWib2HA01kR+Ycw/6GZGX/cPlvyNjWG5JsfyEjTfrhDfUMW0B502n 7W/Qb+LptBeBQ== Message-ID: <7d090781-4fb2-4b54-9f6c-8e9a4ec2749a@kernel.org> Date: Tue, 28 Apr 2026 11:32:25 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] firmware: samsung: fix stale response flag in acpm_prepare_xfer() To: Titouan Ameline , Tudor Ambarus Cc: alim.akhtar@samsung.com, linux-kernel@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org References: <20260426210255.73674-1-titouan.ameline@gmail.com> <84c292d8-d2a0-4c29-bd28-cc00f66c2f43@linaro.org> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 8bit On 27/04/2026 23:37, Titouan Ameline wrote: > I was reading through the driver code and noticed that > acpm_prepare_xfer() only enters the > > if (xfer->rxd) branch to set response = true > with no corresponding else to reset it to false. > > Since seqnum slots are recycled, I traced what happens when a slot > previously used by a response-expecting transfer gets reused by a > fire-and-forget one > > -> the stale true remains and the wrong branch is taken in acpm_get_rx(). > > Le lun. 27 avr. 2026 à 10:48, Tudor Ambarus a écrit : >> This seams to duplicate Tudor's earlier patches and his solution looks more complete, so I will take his work with Reported-by credits. Best regards, Krzysztof