[PATCH] xen-netback: corretly check failed allocation

Since vzalloc can be failed in memory pressure,
return value should be checked and return ENOMEM.

Signed-off-by: Insu Yun <redacted>
---
 drivers/net/xen-netback/xenbus.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c
index 929a6e7..e288246 100644
--- a/drivers/net/xen-netback/xenbus.c
+++ b/drivers/net/xen-netback/xenbus.c

@@ -788,6 +788,11 @@ static void connect(struct backend_info *be)
 	/* Use the number of queues requested by the frontend */
 	be->vif->queues = vzalloc(requested_num_queues *
 				  sizeof(struct xenvif_queue));
+  if (!be->vif->queues)  {
+    xenbus_dev_fatal(dev, -ENOMEM, "allocating queues");
+    return;
+  }
+
 	be->vif->num_queues = requested_num_queues;
 	be->vif->stalled_queues = requested_num_queues;
 

-- 
1.9.1

On Thu, 2015-10-15 at 12:26 -0400, Insu Yun wrote:

Please fix the coding style, perhaps using checkpatch.pl or by observing
the surrounding code.

Ian.

+
 	be->vif->num_queues = requested_num_queues;
 	be->vif->stalled_queues = requested_num_queues;
 

On Thu, Oct 15, 2015 at 12:26:16PM -0400, Insu Yun wrote:

Since vzalloc can be failed in memory pressure,
return value should be checked and return ENOMEM.

This function doesn't return ENOMEM, instead it writes to xenstore to
indicate error. The commit log needs to be updated.

The indentation is wrong. Please configure your email client properly.

And please use "goto err" for error handling -- yes, I understand there
is existing code that returns directly but IMHO that should be fixed
too.

We.

 	be->vif->num_queues = requested_num_queues;
 	be->vif->stalled_queues = requested_num_queues;
 
-- 
1.9.1

Sorry for wrong format, I forgot to change my configuration.

On Thu, Oct 15, 2015 at 1:13 PM, Wei Liu [off-list ref] wrote:

On Thu, Oct 15, 2015 at 12:26:16PM -0400, Insu Yun wrote:

quoted

Since vzalloc can be failed in memory pressure,
return value should be checked and return ENOMEM.

This function doesn't return ENOMEM, instead it writes to xenstore to
indicate error. The commit log needs to be updated.

Good. I will update it.

quoted

Signed-off-by: Insu Yun <redacted>
---
 drivers/net/xen-netback/xenbus.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/xen-netback/xenbus.c

b/drivers/net/xen-netback/xenbus.c

quoted

index 929a6e7..e288246 100644

--- a/drivers/net/xen-netback/xenbus.c
+++ b/drivers/net/xen-netback/xenbus.c

@@ -788,6 +788,11 @@ static void connect(struct backend_info *be)
      /* Use the number of queues requested by the frontend */
      be->vif->queues = vzalloc(requested_num_queues *
                                sizeof(struct xenvif_queue));
+  if (!be->vif->queues)  {
+    xenbus_dev_fatal(dev, -ENOMEM, "allocating queues");
+    return;
+  }
+

The indentation is wrong. Please configure your email client properly.

And please use "goto err" for error handling -- yes, I understand there
is existing code that returns directly but IMHO that should be fixed
too.

Ok. Actually I made a code referring the existing code.

We.

quoted

      be->vif->num_queues = requested_num_queues;
      be->vif->stalled_queues = requested_num_queues;

--
1.9.1

-- 
Regards
Insu Yun

From: Insu Yun <redacted>
Date: Thu, 15 Oct 2015 12:26:16 -0400

This is definitely not indented correctly.