From:   Miaoqian Lin <linmq006@gmail.com>
To:     mathieu.poirier@linaro.org
Cc:     bjorn.andersson@linaro.org, linmq006@gmail.com,
        linux-kernel@vger.kernel.org, linux-remoteproc@vger.kernel.org,
        ohad@wizery.com
Subject: [PATCH v2] remoteproc: Fix NULL vs IS_ERR() checking in rproc_create_trace_file
Date:   Wed,  5 Jan 2022 06:42:01 +0000
Message-Id: <20220105064201.3907-1-linmq006@gmail.com>
In-Reply-To: <20220104174623.GA540353@p14s>
References: <20220104174623.GA540353@p14s>
Precedence: bulk

The debugfs_create_file() function doesn't return NULL.
It returns error pointers. Fix check in rproc_create_trace_file
and make it returns return error pointers.
Fix check in rproc_handle_trace propagate the error code.

Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
---
Changes in v2:
- return PTR_ERR(tfile) in rproc_create_trace_file
- fix check in rproc_handle_trace()
---
 drivers/remoteproc/remoteproc_core.c    | 6 ++++--
 drivers/remoteproc/remoteproc_debugfs.c | 4 ++--
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 775df165eb45..5608408f8eac 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -656,6 +656,7 @@ static int rproc_handle_trace(struct rproc *rproc, void *ptr,
 	struct rproc_debug_trace *trace;
 	struct device *dev = &rproc->dev;
 	char name[15];
+	int ret;
 
 	if (sizeof(*rsc) > avail) {
 		dev_err(dev, "trace rsc is truncated\n");
@@ -684,9 +685,10 @@ static int rproc_handle_trace(struct rproc *rproc, void *ptr,
 
 	/* create the debugfs entry */
 	trace->tfile = rproc_create_trace_file(name, rproc, trace);
-	if (!trace->tfile) {
+	if (IS_ERR(trace->tfile)) {
+		ret = PTR_ERR(trace->tfile);
 		kfree(trace);
-		return -EINVAL;
+		return ret;
 	}
 
 	list_add_tail(&trace->node, &rproc->traces);
diff --git a/drivers/remoteproc/remoteproc_debugfs.c b/drivers/remoteproc/remoteproc_debugfs.c
index b5a1e3b697d9..c1aa7272da1e 100644
--- a/drivers/remoteproc/remoteproc_debugfs.c
+++ b/drivers/remoteproc/remoteproc_debugfs.c
@@ -390,9 +390,9 @@ struct dentry *rproc_create_trace_file(const char *name, struct rproc *rproc,
 
 	tfile = debugfs_create_file(name, 0400, rproc->dbg_dir, trace,
 				    &trace_rproc_ops);
-	if (!tfile) {
+	if (IS_ERR(tfile)) {
 		dev_err(&rproc->dev, "failed to create debugfs trace entry\n");
-		return NULL;
+		return PTR_ERR(tfile);
 	}
 
 	return tfile;
-- 
2.17.1