Re: [PATCH] rpmsg: Make rpmsg_create_ept() propagate error

[kbuild test robot]

Hi Bjorn,

[auto build test WARNING on next-20170505]
[also build test WARNING on v4.11]
[cannot apply to v4.9-rc8 v4.9-rc7 v4.9-rc6]
[if your patch is applied to the wrong git tree, please drop us a note to help 
improve the system]

url:
https://github.com/0day-ci/linux/commits/Bjorn-Andersson/rpmsg-Make-rpmsg_create_ept-propagate-error/20170509-135640
config: arm-multi_v7_defconfig (attached as .config)
compiler: arm-linux-gnueabi-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
wget 
https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O 
~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=arm 

All warnings (new ones prefixed by >>):

   drivers/rpmsg/virtio_rpmsg_bus.c:227:31: sparse: incorrect type in return 
expression (different base types)
   drivers/rpmsg/virtio_rpmsg_bus.c:227:31:expected struct rpmsg_endpoint *
   drivers/rpmsg/virtio_rpmsg_bus.c:227:31:got long
   drivers/rpmsg/virtio_rpmsg_bus.c: In function '__rpmsg_create_ept':
>> drivers/rpmsg/virtio_rpmsg_bus.c:227:18: warning: passing argument 1 of 
>> 'PTR_ERR' makes pointer from integer without a cast [-Wint-conversion]
  return PTR_ERR(-ENOMEM);
 ^
   In file included from include/linux/rwsem.h:17:0,
from include/linux/notifier.h:14,
from include/linux/memory_hotplug.h:6,
from include/linux/mmzone.h:757,
from include/linux/gfp.h:5,
from include/linux/kmod.h:22,
from include/linux/module.h:13,
from drivers/rpmsg/virtio_rpmsg_bus.c:23:
   include/linux/err.h:28:33: note: expected 'const void *' but argument is of 
type 'int'
static inline long __must_check PTR_ERR(__force const void *ptr)
^~~
>> drivers/rpmsg/virtio_rpmsg_bus.c:227:10: warning: return makes pointer from 
>> integer without a cast [-Wint-conversion]
  return PTR_ERR(-ENOMEM);
 ^~~~

vim +/PTR_ERR +227 drivers/rpmsg/virtio_rpmsg_bus.c

   211   */
   212  kfree(ept);
   213  }
   214  
   215  /* for more info, see below documentation of rpmsg_create_ept() */
   216  static struct rpmsg_endpoint *__rpmsg_create_ept(struct virtproc_info 
*vrp,
   217   struct rpmsg_device 
*rpdev,
   218   rpmsg_rx_cb_t cb,
   219   void *priv, u32 addr)
   220  {
   221  int id_min, id_max, id;
   222  struct rpmsg_endpoint *ept;
   223  struct device *dev = rpdev ? &rpdev->dev : &vrp->vdev->dev;
   224  
   225  ept = kzalloc(sizeof(*ept), GFP_KERNEL);
   226  if (!ept)
 > 227  return PTR_ERR(-ENOMEM);
   228  
   229  kref_init(&ept->refcount);
   230  mutex_init(&ept->cb_lock);
   231  
   232  ept->rpdev = rpdev;
   233  ept->cb = cb;
   234  ept->priv = priv;
   235  ept->ops = &virtio_endpoint_ops;

---
0-DAY kernel test infrastructureOpen Source Technology Center
https://lists.01.org/pipermail/kbuild-all   Intel Corporation


.config.gz
Description: application/gzip

[PATCH] rpmsg: Make rpmsg_create_ept() propagate error

[Bjorn Andersson]

Make the rpmsg_create_ept() return an ERR_PTR() rather than NULL, as
this is common practice throughout the kernel and I got the first two
clients of this API wrong.

Signed-off-by: Bjorn Andersson 
---
 drivers/rpmsg/qcom_smd.c | 8 
 drivers/rpmsg/rpmsg_char.c   | 4 ++--
 drivers/rpmsg/rpmsg_core.c   | 6 +++---
 drivers/rpmsg/virtio_rpmsg_bus.c | 4 ++--
 4 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/rpmsg/qcom_smd.c b/drivers/rpmsg/qcom_smd.c
index a0a39a8821a3..cbc20ebba0a3 100644
--- a/drivers/rpmsg/qcom_smd.c
+++ b/drivers/rpmsg/qcom_smd.c
@@ -860,16 +860,16 @@ static struct rpmsg_endpoint *qcom_smd_create_ept(struct 
rpmsg_device *rpdev,
(channel = qcom_smd_find_channel(edge, name)) != NULL,
HZ);
if (!ret)
-   return NULL;
+   return ERR_PTR(-ETIMEDOUT);
 
if (channel->state != SMD_CHANNEL_CLOSED) {
dev_err(&rpdev->dev, "channel %s is busy\n", channel->name);
-   return NULL;
+   return ERR_PTR(-EBUSY);
}
 
qsept = kzalloc(sizeof(*qsept), GFP_KERNEL);
if (!qsept)
-   return NULL;
+   return ERR_PTR(-ENOMEM);
 
ept = &qsept->ept;
 
@@ -892,7 +892,7 @@ static struct rpmsg_endpoint *qcom_smd_create_ept(struct 
rpmsg_device *rpdev,
 free_ept:
channel->qsept = NULL;
kref_put(&ept->refcount, __ept_release);
-   return NULL;
+   return ERR_PTR(ret);
 }
 
 static void qcom_smd_destroy_ept(struct rpmsg_endpoint *ept)
diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
index 0ca2ccc09ca6..35918866d3fa 100644
--- a/drivers/rpmsg/rpmsg_char.c
+++ b/drivers/rpmsg/rpmsg_char.c
@@ -138,10 +138,10 @@ static int rpmsg_eptdev_open(struct inode *inode, struct 
file *filp)
get_device(dev);
 
ept = rpmsg_create_ept(rpdev, rpmsg_ept_cb, eptdev, eptdev->chinfo);
-   if (!ept) {
+   if (IS_ERR(ept)) {
dev_err(dev, "failed to open %s\n", eptdev->chinfo.name);
put_device(dev);
-   return -EINVAL;
+   return PTR_ERR(ept);
}
 
eptdev->ept = ept;
diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
index 600f5f9f7431..91dc76f250fa 100644
--- a/drivers/rpmsg/rpmsg_core.c
+++ b/drivers/rpmsg/rpmsg_core.c
@@ -65,7 +65,7 @@
  * dynamically assign them an available rpmsg address (drivers should have
  * a very good reason why not to always use RPMSG_ADDR_ANY here).
  *
- * Returns a pointer to the endpoint on success, or NULL on error.
+ * Returns a pointer to the endpoint on success, or ERR_PTR() on error.
  */
 struct rpmsg_endpoint *rpmsg_create_ept(struct rpmsg_device *rpdev,
rpmsg_rx_cb_t cb, void *priv,
@@ -411,9 +411,9 @@ static int rpmsg_dev_probe(struct device *dev)
chinfo.dst = RPMSG_ADDR_ANY;
 
ept = rpmsg_create_ept(rpdev, rpdrv->callback, NULL, chinfo);
-   if (!ept) {
+   if (IS_ERR(ept)) {
dev_err(dev, "failed to create endpoint\n");
-   err = -ENOMEM;
+   err = PTR_ERR(ept);
goto out;
}
 
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 4848da89431f..7fd49ed4847a 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -224,7 +224,7 @@ static struct rpmsg_endpoint *__rpmsg_create_ept(struct 
virtproc_info *vrp,
 
ept = kzalloc(sizeof(*ept), GFP_KERNEL);
if (!ept)
-   return NULL;
+   return PTR_ERR(-ENOMEM);
 
kref_init(&ept->refcount);
mutex_init(&ept->cb_lock);
@@ -260,7 +260,7 @@ static struct rpmsg_endpoint *__rpmsg_create_ept(struct 
virtproc_info *vrp,
 free_ept:
mutex_unlock(&vrp->endpoints_lock);
kref_put(&ept->refcount, __ept_release);
-   return NULL;
+   return ERR_PTR(id);
 }
 
 static struct rpmsg_endpoint *virtio_rpmsg_create_ept(struct rpmsg_device 
*rpdev,
-- 
2.12.0