[dpdk-dev] [PATCH V20 3/4] igb_uio: fix uio release issue when hot unplug

[Jeff Guo]

when device being hot unplug, release a none exist uio resource will
result kernel null pointer error, so this patch will check if device
has been remove before release uio release procedure, if so just return
back.

Signed-off-by: Jeff Guo <jia.guo at intel.com>
---
v20->v19:
split patch independently.
---
 kernel/linux/igb_uio/igb_uio.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/kernel/linux/igb_uio/igb_uio.c b/kernel/linux/igb_uio/igb_uio.c
index cbc5ab6..c296332 100644
--- a/kernel/linux/igb_uio/igb_uio.c
+++ b/kernel/linux/igb_uio/igb_uio.c
@@ -344,6 +344,10 @@ igbuio_pci_release(struct uio_info *info, struct inode *inode)
 	struct rte_uio_pci_dev *udev = info->priv;
 	struct pci_dev *dev = udev->pdev;
 
+	/* check if device has been remove before release */
+	if ((&dev->dev.kobj)->state_remove_uevent_sent == 1)
+		return -1;
+
 	mutex_lock(&udev->lock);
 	if (--udev->refcnt > 0) {
 		mutex_unlock(&udev->lock);
-- 
2.7.4