xen-front-pgdir-shbuf: don't record wrong grant handle upon error

In order for subsequent unmapping to not mistakenly unmap handle 0,
record a perceived always-invalid one instead.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Link: https://lore.kernel.org/r/82414b0f-1b63-5509-7c1d-5bcc8239a3de@suse.com
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
This commit is contained in:
Jan Beulich 2021-02-23 17:26:21 +01:00 committed by Boris Ostrovsky
parent 43135df0d7
commit 53f131c284

View File

@ -305,11 +305,18 @@ static int backend_map(struct xen_front_pgdir_shbuf *buf)
/* Save handles even if error, so we can unmap. */
for (cur_page = 0; cur_page < buf->num_pages; cur_page++) {
buf->backend_map_handles[cur_page] = map_ops[cur_page].handle;
if (unlikely(map_ops[cur_page].status != GNTST_okay))
if (likely(map_ops[cur_page].status == GNTST_okay)) {
buf->backend_map_handles[cur_page] =
map_ops[cur_page].handle;
} else {
buf->backend_map_handles[cur_page] =
INVALID_GRANT_HANDLE;
if (!ret)
ret = -ENXIO;
dev_err(&buf->xb_dev->dev,
"Failed to map page %d: %d\n",
cur_page, map_ops[cur_page].status);
}
}
if (ret) {