提交 b6497b38 编写于 作者: I Ian Campbell 提交者: Stefano Stabellini

xen: privcmd: do not return pages which we have failed to unmap

This failure represents a hypervisor issue, but if it does occur then nothing
good can come of returning pages which still refer to a foreign owned page
into the general allocation pool.

Instead we are forced to leak them. Log that we have done so.

The potential for failure only exists for autotranslated guest (e.g. ARM and
x86 PVH).
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
上级 c94cae53
......@@ -533,12 +533,17 @@ static void privcmd_close(struct vm_area_struct *vma)
{
struct page **pages = vma->vm_private_data;
int numpgs = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
int rc;
if (!xen_feature(XENFEAT_auto_translated_physmap) || !numpgs || !pages)
return;
xen_unmap_domain_mfn_range(vma, numpgs, pages);
free_xenballooned_pages(numpgs, pages);
rc = xen_unmap_domain_mfn_range(vma, numpgs, pages);
if (rc == 0)
free_xenballooned_pages(numpgs, pages);
else
pr_crit("unable to unmap MFN range: leaking %d pages. rc=%d\n",
numpgs, rc);
kfree(pages);
}
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册