Next patches need to check suspend flag at this work item, and the rwlock is used to protect the suspend flag update. If the work takes the rwlock too it will produce a deadlock.
Signed-off-by: Eugenio Pérez <[email protected]> --- drivers/vdpa/vdpa_user/vduse_dev.c | 63 ++++++++++++++++-------------- 1 file changed, 33 insertions(+), 30 deletions(-) diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index eff104f90cee..0f15575df394 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -501,44 +501,47 @@ static void vduse_dev_reset(struct vduse_dev *dev) vduse_domain_reset_bounce_map(domain); } - down_write(&dev->rwsem); + scoped_guard(rwsem_write, &dev->rwsem) { + dev->status = 0; + dev->driver_features = 0; + dev->generation++; + spin_lock(&dev->irq_lock); + dev->config_cb.callback = NULL; + dev->config_cb.private = NULL; + spin_unlock(&dev->irq_lock); + + for (i = 0; i < dev->vq_num; i++) { + struct vduse_virtqueue *vq = dev->vqs[i]; + + vq->ready = false; + vq->desc_addr = 0; + vq->driver_addr = 0; + vq->device_addr = 0; + vq->num = 0; + memset(&vq->state, 0, sizeof(vq->state)); + + spin_lock(&vq->kick_lock); + vq->kicked = false; + if (vq->kickfd) + eventfd_ctx_put(vq->kickfd); + vq->kickfd = NULL; + spin_unlock(&vq->kick_lock); + + spin_lock(&vq->irq_lock); + vq->cb.callback = NULL; + vq->cb.private = NULL; + vq->cb.trigger = NULL; + spin_unlock(&vq->irq_lock); + } + } - dev->status = 0; - dev->driver_features = 0; - dev->generation++; - spin_lock(&dev->irq_lock); - dev->config_cb.callback = NULL; - dev->config_cb.private = NULL; - spin_unlock(&dev->irq_lock); flush_work(&dev->inject); - for (i = 0; i < dev->vq_num; i++) { struct vduse_virtqueue *vq = dev->vqs[i]; - vq->ready = false; - vq->desc_addr = 0; - vq->driver_addr = 0; - vq->device_addr = 0; - vq->num = 0; - memset(&vq->state, 0, sizeof(vq->state)); - - spin_lock(&vq->kick_lock); - vq->kicked = false; - if (vq->kickfd) - eventfd_ctx_put(vq->kickfd); - vq->kickfd = NULL; - spin_unlock(&vq->kick_lock); - - spin_lock(&vq->irq_lock); - vq->cb.callback = NULL; - vq->cb.private = NULL; - vq->cb.trigger = NULL; - spin_unlock(&vq->irq_lock); 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, -- 2.54.0
