The refcount check for dedicuated workqueue (dwq) is off by one and allows
more than 1 user to open the char device. Fix check so only a single user
can open the device.
Fixes: 42d279f9137a ("dmaengine: idxd: add char driver to expose submission portal to userland")
Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
---
drivers/dma/idxd/cdev.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/dma/idxd/cdev.c b/drivers/dma/idxd/cdev.c
index e4379ba04a9a..f5e43f65a5ed 100644
--- a/drivers/dma/idxd/cdev.c
+++ b/drivers/dma/idxd/cdev.c
@@ -84,9 +84,9 @@ static int idxd_cdev_open(struct inode *inode, struct file *filp)
dev = &idxd->pdev->dev;
idxd_cdev = &wq->idxd_cdev;
- dev_dbg(dev, "%s called\n", __func__);
+ dev_dbg(dev, "%s called: %d\n", __func__, idxd_wq_refcount(wq));
- if (idxd_wq_refcount(wq) > 1 && wq_dedicated(wq))
+ if (idxd_wq_refcount(wq) > 0 && wq_dedicated(wq))
return -EBUSY;
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
