Messages in this thread Patch in this message | | | From | Sasha Levin <> | Subject | [PATCH AUTOSEL for 4.9 50/52] xen/gntdev: Fix partial gntdev_mmap() cleanup | Date | Sat, 3 Feb 2018 18:04:00 +0000 |
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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> --- drivers/xen/gntdev.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 54c4c4183fbe..910b5d40c6e9 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -1077,8 +1077,10 @@ 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; } -- 2.11.0
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