Currently vhost_vdpa_cleanup() unmaps the DMA mappings by calling
`iommu_unmap(v->domain, map->start, map->size);`
from vhost_vdpa_general_unmap() when the parent vDPA driver doesn't
provide DMA config operations.
However, the IOMMU domain referred to by `v->domain` is freed in
vhost_vdpa_free_domain() before vhost_vdpa_cleanup() in
vhost_vdpa_release() which results in NULL pointer de-reference.
Accordingly, moving the call to vhost_vdpa_free_domain() in
vhost_vdpa_cleanup() would makes sense. This will also help
detaching the dma device in error handling of vhost_vdpa_alloc_domain().
This issue was observed on terminating QEMU with SIGQUIT.
Fixes: 037d4305569a ("vhost-vdpa: call vhost_vdpa_cleanup during the release")
Signed-off-by: Gautam Dawar <gautam.dawar@xxxxxxx>
---
drivers/vhost/vdpa.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index ec32f785dfde..b7657984dd8d 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -1134,6 +1134,7 @@ static int vhost_vdpa_alloc_domain(struct vhost_vdpa *v)
err_attach:
iommu_domain_free(v->domain);
+ v->domain = NULL;
return ret;
}
@@ -1178,6 +1179,7 @@ static void vhost_vdpa_cleanup(struct vhost_vdpa *v)
vhost_vdpa_remove_as(v, asid);
}
+ vhost_vdpa_free_domain(v);
vhost_dev_cleanup(&v->vdev);
kfree(v->vdev.vqs);
}
@@ -1250,7 +1252,6 @@ static int vhost_vdpa_release(struct inode *inode, struct file *filep)
vhost_vdpa_clean_irq(v);
vhost_vdpa_reset(v);
vhost_dev_stop(&v->vdev);
- vhost_vdpa_free_domain(v);
vhost_vdpa_config_put(v);
vhost_vdpa_cleanup(v);
mutex_unlock(&d->mutex);
--
2.30.1
