From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 02694435AB0; Thu, 30 Jul 2026 14:59:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785423596; cv=none; b=nx3W9EIbk1TNXgoyJAL6Ay1VuAruEn1axrvZZtMmEP9eJIUYae7WsxPAvVYzDYQ+3iiwv0PYfXr/JecQ+KB9XEtKe5jDFX/L3g7N15hNA0QLGadsVBgssy5U90waWV5gmtb4DeVMDfFC8x5fyPzb/UxMvklw+erc4Ai3YFoe3zo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785423596; c=relaxed/simple; bh=aiYAHefjBQJFglSNZI26xUnK48amc3SLaspPlQ6avRg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=psuI6ZZd9gzEAbM4hm7j9tMhVC9nVUjmoS4lD7VkvrY4PhaVhFrqGXM7XngSThDvnZRGcORkXmOK2gWaLJ8vSLJHdy7VbaYTcMLD7/18KbOLBSqpAbpXj/+KG/QyjgJdRTWG1rT8sLWA1CxMn8QPyswj52kthW/KU+iAH3x9Nz4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jKBZ+HG4; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="jKBZ+HG4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 581491F000E9; Thu, 30 Jul 2026 14:59:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785423594; bh=4GFnUfmjLkMH4OmMGq/9H+H5grtM/Jv8lty7J75OFS4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=jKBZ+HG4T3U5l5vq9jOyNDU42RKuRHtAZu7DkPU7Yb8Y+V5vpUEfHQiI06Gs16KF7 V5Ki1UPYlLTRaUpeg9atQ9uh9ezedfUAIVp0xgsGkQ6y8uKRU7GjGY8d0R9pMCG+jC 5Y3nZVcFkdRxttQbUGfaXBVwUCSd65H76U9xt0vI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Robert Mader , Mikhail Gavrilov , Vivek Kasireddy , Sasha Levin Subject: [PATCH 6.18 099/675] udmabuf: Ensure to perform cache synchronisation in begin_cpu_udmabuf() Date: Thu, 30 Jul 2026 16:07:09 +0200 Message-ID: <20260730141447.238085872@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141445.110192266@linuxfoundation.org> References: <20260730141445.110192266@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Robert Mader [ Upstream commit 1d0e25c1ddf2063c499264fb2ba0fa6a3e4f8a00 ] The message of commit 504e2b4ab97a ("dma-buf/udmabuf: skip redundant cpu sync to fix cacheline EEXIST warning") says: > The CPU sync at map/unmap time is also redundant for udmabuf: > begin_cpu_udmabuf() and end_cpu_udmabuf() already perform explicit > cache synchronization via dma_sync_sgtable_for_cpu/device() when CPU > access is requested through the dma-buf interface. This, however, does not apply to the first time begin_cpu_udmabuf() is called on an udmabuf, in which case the implementation previously relied on get_sg_table() to perform the cache synchronisation. Ensure to call dma_sync_sgtable_for_cpu() in that case as well. Fixes: 504e2b4ab97a ("dma-buf/udmabuf: skip redundant cpu sync to fix cacheline EEXIST warning") Signed-off-by: Robert Mader Reviewed-by: Mikhail Gavrilov Signed-off-by: Vivek Kasireddy Link: https://patch.msgid.link/20260627105725.9083-1-robert.mader@collabora.com Signed-off-by: Sasha Levin --- drivers/dma-buf/udmabuf.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c index be47d1ff6c508b..30b0f0c72e928c 100644 --- a/drivers/dma-buf/udmabuf.c +++ b/drivers/dma-buf/udmabuf.c @@ -249,21 +249,22 @@ static int begin_cpu_udmabuf(struct dma_buf *buf, { struct udmabuf *ubuf = buf->priv; struct device *dev = ubuf->device->this_device; - int ret = 0; if (!ubuf->sg) { ubuf->sg = get_sg_table(dev, buf, direction); if (IS_ERR(ubuf->sg)) { + int ret; + ret = PTR_ERR(ubuf->sg); ubuf->sg = NULL; + return ret; } else { ubuf->sg_dir = direction; } - } else { - dma_sync_sgtable_for_cpu(dev, ubuf->sg, direction); } - return ret; + dma_sync_sgtable_for_cpu(dev, ubuf->sg, direction); + return 0; } static int end_cpu_udmabuf(struct dma_buf *buf, -- 2.53.0