diff options
| author | Xie Yongji <xieyongji@bytedance.com> | 2021-09-29 11:30:50 +0300 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2021-10-22 13:49:14 +0300 |
| commit | 0943aacf5ae10471b68a702c022b42c89e91ba9e (patch) | |
| tree | 4c49b7212b76402000db34aab1f296225fabd604 /drivers/vdpa | |
| parent | 1394103fd72ce9c67d20f882a93d59403c8da057 (diff) | |
| download | linux-0943aacf5ae10471b68a702c022b42c89e91ba9e.tar.xz | |
vduse: Fix race condition between resetting and irq injecting
The interrupt might be triggered after a reset since there is
no synchronization between resetting and irq injecting. And it
might break something if the interrupt is delayed until a new
round of device initialization.
Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace")
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20210929083050.88-1-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'drivers/vdpa')
| -rw-r--r-- | drivers/vdpa/vdpa_user/vduse_dev.c | 37 |
1 files changed, 25 insertions, 12 deletions
diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index cefb301b2ee4..841667a896dd 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -80,6 +80,7 @@ struct vduse_dev { struct vdpa_callback config_cb; struct work_struct inject; spinlock_t irq_lock; + struct rw_semaphore rwsem; int minor; bool broken; bool connected; @@ -410,6 +411,8 @@ static void vduse_dev_reset(struct vduse_dev *dev) if (domain->bounce_map) vduse_domain_reset_bounce_map(domain); + down_write(&dev->rwsem); + dev->status = 0; dev->driver_features = 0; dev->generation++; @@ -443,6 +446,8 @@ static void vduse_dev_reset(struct vduse_dev *dev) flush_work(&vq->inject); flush_work(&vq->kick); } + + up_write(&dev->rwsem); } static int vduse_vdpa_set_vq_address(struct vdpa_device *vdpa, u16 idx, @@ -885,6 +890,23 @@ static void vduse_vq_irq_inject(struct work_struct *work) spin_unlock_irq(&vq->irq_lock); } +static int vduse_dev_queue_irq_work(struct vduse_dev *dev, + struct work_struct *irq_work) +{ + int ret = -EINVAL; + + down_read(&dev->rwsem); + if (!(dev->status & VIRTIO_CONFIG_S_DRIVER_OK)) + goto unlock; + + ret = 0; + queue_work(vduse_irq_wq, irq_work); +unlock: + up_read(&dev->rwsem); + + return ret; +} + static long vduse_dev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -966,12 +988,7 @@ 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); + ret = vduse_dev_queue_irq_work(dev, &dev->inject); break; case VDUSE_VQ_SETUP: { struct vduse_vq_config config; @@ -1049,10 +1066,6 @@ 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; @@ -1061,9 +1074,8 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd, if (index >= dev->vq_num) break; - ret = 0; index = array_index_nospec(index, dev->vq_num); - queue_work(vduse_irq_wq, &dev->vqs[index].inject); + ret = vduse_dev_queue_irq_work(dev, &dev->vqs[index].inject); break; } default: @@ -1144,6 +1156,7 @@ static struct vduse_dev *vduse_dev_create(void) INIT_LIST_HEAD(&dev->send_list); INIT_LIST_HEAD(&dev->recv_list); spin_lock_init(&dev->irq_lock); + init_rwsem(&dev->rwsem); INIT_WORK(&dev->inject, vduse_dev_irq_inject); init_waitqueue_head(&dev->waitq); |