Re: [PATCH] vduse: Disallow injecting interrupt before DRIVER_OK is set

The interrupt callback should not be triggered before DRIVER_OK
is set. Otherwise, it might break the virtio device driver.
So let's add a check to avoid the unexpected behavior.

Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace")
Signed-off-by: Xie Yongji <redacted>
---
 drivers/vdpa/vdpa_user/vduse_dev.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c
index 29a38ecba19e..972c13a7e5da 100644
--- a/drivers/vdpa/vdpa_user/vduse_dev.c
+++ b/drivers/vdpa/vdpa_user/vduse_dev.c

@@ -968,6 +968,10 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd,
                break;
        }
        case VDUSE_DEV_INJECT_CONFIG_IRQ:
+               ret = -EINVAL;
+               if (!(dev->status & VIRTIO_CONFIG_S_DRIVER_OK))
+                       break;
+

                ret = 0;
                queue_work(vduse_irq_wq, &dev->inject);
                break;

@@ -1047,6 +1051,10 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd,
        case VDUSE_VQ_INJECT_IRQ: {
                u32 index;

+               ret = -EINVAL;
+               if (!(dev->status & VIRTIO_CONFIG_S_DRIVER_OK))
+                       break;
+
                ret = -EFAULT;
                if (get_user(index, (u32 __user *)argp))
                        break;
--

2.11.0