x86/xen: use vmap() to map grant table pages in PVH guests

Commit b7dd0e350e (x86/xen: safely map and unmap grant frames when
in atomic context) causes PVH guests to crash in
arch_gnttab_map_shared() when they attempted to map the pages for the
grant table.

This use of a PV-specific function during the PVH grant table setup is
non-obvious and not needed.  The standard vmap() function does the
right thing.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reported-by: Mukesh Rathor <mukesh.rathor@oracle.com>
Tested-by: Mukesh Rathor <mukesh.rathor@oracle.com>
Cc: stable@vger.kernel.org
This commit is contained in:
David Vrabel 2014-08-05 11:49:19 +01:00
parent 8d5999df35
commit 7d951f3ccb

View File

@ -118,6 +118,7 @@ static int __init xlated_setup_gnttab_pages(void)
{
struct page **pages;
xen_pfn_t *pfns;
void *vaddr;
int rc;
unsigned int i;
unsigned long nr_grant_frames = gnttab_max_grant_frames();
@ -143,21 +144,20 @@ static int __init xlated_setup_gnttab_pages(void)
for (i = 0; i < nr_grant_frames; i++)
pfns[i] = page_to_pfn(pages[i]);
rc = arch_gnttab_map_shared(pfns, nr_grant_frames, nr_grant_frames,
&xen_auto_xlat_grant_frames.vaddr);
if (rc) {
vaddr = vmap(pages, nr_grant_frames, 0, PAGE_KERNEL);
if (!vaddr) {
pr_warn("%s Couldn't map %ld pfns rc:%d\n", __func__,
nr_grant_frames, rc);
free_xenballooned_pages(nr_grant_frames, pages);
kfree(pages);
kfree(pfns);
return rc;
return -ENOMEM;
}
kfree(pages);
xen_auto_xlat_grant_frames.pfn = pfns;
xen_auto_xlat_grant_frames.count = nr_grant_frames;
xen_auto_xlat_grant_frames.vaddr = vaddr;
return 0;
}