linux-kernel - [PATCH v3 19/22] soundwire: stream: only prepare stream when it is configured.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20191114181702.22254-20-pierre-louis.bossart@linux.intel.com>
Date:   Thu, 14 Nov 2019 12:16:59 -0600
From:   Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>
To:     alsa-devel@...a-project.org
Cc:     linux-kernel@...r.kernel.org, tiwai@...e.de, broonie@...nel.org,
        vkoul@...nel.org, gregkh@...uxfoundation.org, jank@...ence.com,
        srinivas.kandagatla@...aro.org, slawomir.blauciak@...el.com,
        Bard liao <yung-chuan.liao@...ux.intel.com>,
        Rander Wang <rander.wang@...ux.intel.com>,
        Ranjani Sridharan <ranjani.sridharan@...ux.intel.com>,
        Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>,
        Sanyog Kale <sanyog.r.kale@...el.com>
Subject: [PATCH v3 19/22] soundwire: stream: only prepare stream when it is configured.

From: Bard Liao <yung-chuan.liao@...ux.intel.com>

We don't need to prepare the stream again if the stream is already
prepared.

sdw_prepare_stream() could be called multiple times without calling
sdw_deprepare_stream(). We call sdw_prepare_stream() in the prepare
dai ops and sdw_deprepare_stream() in the hw_free dai ops. If an xrun
happens, sdw_prepare_stream() will be called but
sdw_deprepare_stream() will not, which results in an imbalance and an
invalid total bandwidth.

Signed-off-by: Bard Liao <yung-chuan.liao@...ux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>
---
 drivers/soundwire/stream.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/soundwire/stream.c b/drivers/soundwire/stream.c
index 6aa0b5d370c0..bd0bddf73830 100644
--- a/drivers/soundwire/stream.c
+++ b/drivers/soundwire/stream.c
@@ -1544,7 +1544,7 @@ static int _sdw_prepare_stream(struct sdw_stream_runtime *stream)
  */
 int sdw_prepare_stream(struct sdw_stream_runtime *stream)
 {
-	int ret = 0;
+	int ret;
 
 	if (!stream) {
 		pr_err("SoundWire: Handle not found for stream\n");
@@ -1553,6 +1553,11 @@ int sdw_prepare_stream(struct sdw_stream_runtime *stream)
 
 	sdw_acquire_bus_lock(stream);
 
+	if (stream->state == SDW_STREAM_PREPARED) {
+		ret = 0;
+		goto state_err;
+	}
+
 	if (stream->state != SDW_STREAM_CONFIGURED &&
 	    stream->state != SDW_STREAM_DEPREPARED &&
 	    stream->state != SDW_STREAM_DISABLED) {
-- 
2.20.1