Re: [RFC PATCH] vhost-vdpa: mark vhost device invalid to reflect vdpa device unregistration
From: Jason Wang <hidden>
Date: 2021-07-05 03:48:51
Also in:
lkml, netdev, virtualization
在 2021/7/5 上午4:52, gautam.dawar@xilinx.com 写道:
quoted hunk ↗ jump to hunk
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);@@ -1091,11 +1122,13 @@ static void vhost_vdpa_remove(struct vdpa_device *vdpa) opened = atomic_cmpxchg(&v->opened, 0, 1); if (!opened) break; - wait_for_completion_timeout(&v->completion, - msecs_to_jiffies(1000)); - dev_warn_once(&v->dev, - "%s waiting for/dev/%s to be closed\n", - __func__, dev_name(&v->dev)); + if (!wait_for_completion_timeout(&v->completion, + msecs_to_jiffies(1000))) { + dev_warn(&v->dev, + "%s/dev/%s in use, continue..\n", + __func__, dev_name(&v->dev)); + break; + } } while (1); put_device(&v->dev); + v->dev_invalid = true;
Besides the mapping handling mentioned by Michael. I think this can lead use-after-free. put_device may release the memory. Another fundamental issue, vDPA is the parent of vhost-vDPA device. I'm not sure the device core can allow the parent to go away first. Thanks