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 C57ED4519BA; Thu, 30 Jul 2026 16:18:42 +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=1785428323; cv=none; b=mUolruAL1n6sRz37NmEDgoQmu/8UQBhsO+lt0yRYnex0nNWYNVrqWToujP1Y00no/Xm1rlMG3Pd6Js2JZWwdLyfmqwdBfgsCtCRvRHaTRhJrPapM9SDZpZVEUvuqbYANktd0knoViNi3nX6Y99rOYcgSk6Jz39ae2Qe1QPPRgPQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785428323; c=relaxed/simple; bh=vYkeAwCZ9DjnVnHCbDLz0SUXpfNEKO+Lk3lkN1Vfs2M=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jWipG1ljuJq1lrQTwyEIkFhZ0nTXYoLrUwub1EA15OvXya8dWStPoTKzmoIskTuNH36V8W/eD78CDZI0lLMCS7YRioa9QZ9cimDlyzAVLJXNfwDQJM2pxyV0f1Gc4k/SD+uHliI9cMU9sij8ZLjhazbmdwBxqHVbxKkMWxGSLpg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=do4VWfCI; 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="do4VWfCI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D99871F000E9; Thu, 30 Jul 2026 16:18:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785428322; bh=1M8Ry8yChjn3NXD6HP4NzfdVvR0bFZxJB3Nphk/uiDs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=do4VWfCIqpgcNgHahdZ7Ah+Tnw62wnDdZDJO/8gs8L6bcd/KlSOkWItT8tpngyiSq G/iB+n8ob8eM4XP/9HVA4Ii5tAypk96t54EIJDo3tsC9K8eXA+TEyQvvRZEpti6iV/ leKpu3k5X2cYboWzBqHMX5EUl5V+z7UAIodGeoiY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Robert Mader , Mikhail Gavrilov , Vivek Kasireddy Subject: [PATCH 6.6 482/484] udmabuf: Ensure to perform cache synchronisation in begin_cpu_udmabuf() Date: Thu, 30 Jul 2026 16:16:19 +0200 Message-ID: <20260730141433.964694474@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141423.392222816@linuxfoundation.org> References: <20260730141423.392222816@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 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Robert Mader commit 1d0e25c1ddf2063c499264fb2ba0fa6a3e4f8a00 upstream. 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: Greg Kroah-Hartman --- drivers/dma-buf/udmabuf.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) --- a/drivers/dma-buf/udmabuf.c +++ b/drivers/dma-buf/udmabuf.c @@ -155,21 +155,22 @@ static int begin_cpu_udmabuf(struct dma_ { 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,