| From foo@baz Wed Feb 28 16:16:23 CET 2018 |
| From: Ross Lagerwall <ross.lagerwall@citrix.com> |
| Date: Tue, 9 Jan 2018 12:10:22 +0000 |
| Subject: xen/gntdev: Fix partial gntdev_mmap() cleanup |
| |
| From: Ross Lagerwall <ross.lagerwall@citrix.com> |
| |
| |
| [ Upstream commit cf2acf66ad43abb39735568f55e1f85f9844e990 ] |
| |
| When cleaning up after a partially successful gntdev_mmap(), unmap the |
| successfully mapped grant pages otherwise Xen will kill the domain if |
| in debug mode (Attempt to implicitly unmap a granted PTE) or Linux will |
| kill the process and emit "BUG: Bad page map in process" if Xen is in |
| release mode. |
| |
| This is only needed when use_ptemod is true because gntdev_put_map() |
| will unmap grant pages itself when use_ptemod is false. |
| |
| Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> |
| Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> |
| Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> |
| Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/xen/gntdev.c | 4 +++- |
| 1 file changed, 3 insertions(+), 1 deletion(-) |
| |
| --- a/drivers/xen/gntdev.c |
| +++ b/drivers/xen/gntdev.c |
| @@ -817,8 +817,10 @@ unlock_out: |
| out_unlock_put: |
| mutex_unlock(&priv->lock); |
| out_put_map: |
| - if (use_ptemod) |
| + if (use_ptemod) { |
| map->vma = NULL; |
| + unmap_grant_pages(map, 0, map->count); |
| + } |
| gntdev_put_map(priv, map); |
| return err; |
| } |