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 A0DED36C9D8 for ; Sat, 28 Feb 2026 18:12:46 +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=1772302366; cv=none; b=eWXBVNsaPCUm6ZV4rMKJmy8CgdLoH7GHvKDZY/CHQuCEtUe/EHGh2n+h0SGDj+wxV+WUaWCVbuQ1HrPc0zZR+//VboUbQOOPsPFrBUvMrpUlGfFgoaKyJXhMxZ88PxEQvjLM867pkE3QlN0P5WG+0V1t91fOow2fldJ+Tu6Us9I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302366; c=relaxed/simple; bh=QWaiw5pYyeRYgIgu6IPOmBmCDxkx/CVcIhSk5pvFEx4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qno9Jn+jnl60in1EGmCZ5WsTpIeO5Qhv0vRPNzyFG244PxtiFAP4d2RoZl78myhPJS9VaPXIbWdSJ6DsvrQsCxS5VwJHmaYh0NAVnLwLYcGzrvK8qentIVd2kE44udpTlWcwYzCMEo5TeEB38rT7VTfg+697UT/cweOf69Z6+Nk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=evL5niQi; 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="evL5niQi" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0DFFAC116D0; Sat, 28 Feb 2026 18:12:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772302366; bh=QWaiw5pYyeRYgIgu6IPOmBmCDxkx/CVcIhSk5pvFEx4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=evL5niQi164SQrJakhs20jd2V7tYX8UGDkOaHgvJ96VctctBryiSvYTU/LVD+l0b3 oLmvYiLPKz4UF8IPCENMtxcTF9Hrp1CUgGft+pGE1xXPPMXdUpnap2Hys9RtVsP3cP gQTYLhypEYMPu80tVt8rolhMa12UTdMTCI4udHpDjh1+B0rC+O2GQFO8mZnnRrj1GH DYSQ2NHAI375e9KE9e3woR1GJ9Dh25JsbN5gW58JzfLvfe+lG30p5lmH1oKsuUvSS3 CZxFmE/TsHpKwBds35f9R6fAmkFv0nSH9fQgZmeKWUIAi71mq5kpic3kB5iZcABmtT I2MXqRp+bGCjw== From: Sasha Levin To: patches@lists.linux.dev Cc: Matt Johnston , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 094/232] mctp i2c: initialise event handler read bytes Date: Sat, 28 Feb 2026 13:09:07 -0500 Message-ID: <20260228181127.1592657-94-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228181127.1592657-1-sashal@kernel.org> References: <20260228181127.1592657-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Matt Johnston [ Upstream commit 2a14e91b6d76639dac70ea170f4384c1ee3cb48d ] Set a 0xff value for i2c reads of an mctp-i2c device. Otherwise reads will return "val" from the i2c bus driver. For i2c-aspeed and i2c-npcm7xx that is a stack uninitialised u8. Tested with "i2ctransfer -y 1 r10@0x34" where 0x34 is a mctp-i2c instance, now it returns all 0xff. Fixes: f5b8abf9fc3d ("mctp i2c: MCTP I2C binding driver") Signed-off-by: Matt Johnston Link: https://patch.msgid.link/20260113-mctp-read-fix-v1-1-70c4b59c741c@codeconstruct.com.au Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/mctp/mctp-i2c.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/mctp/mctp-i2c.c b/drivers/net/mctp/mctp-i2c.c index 1d0c516842793..f77389c7006f8 100644 --- a/drivers/net/mctp/mctp-i2c.c +++ b/drivers/net/mctp/mctp-i2c.c @@ -244,7 +244,10 @@ static int mctp_i2c_slave_cb(struct i2c_client *client, switch (event) { case I2C_SLAVE_READ_REQUESTED: + case I2C_SLAVE_READ_PROCESSED: + /* MCTP I2C transport only uses writes */ midev->rx_pos = 0; + *val = 0xff; break; case I2C_SLAVE_WRITE_RECEIVED: if (midev->rx_pos < MCTP_I2C_BUFSZ) { -- 2.51.0