[PATCH] xen/gnttab: Log when grant_table_init() fails

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

... so debug builds can see what went wrong, rather than getting an
unqualified -EINVAL out domain creation.

Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
CC: Jan Beulich <JBeulich@xxxxxxxx>
CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>
CC: Wei Liu <wl@xxxxxxx>
CC: Stefano Stabellini <sstabellini@xxxxxxxxxx>
CC: Julien Grall <julien@xxxxxxx>
CC: Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>
---
 xen/common/grant_table.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/xen/common/grant_table.c b/xen/common/grant_table.c
index b31d404579..cbdd6e2f4e 100644
--- a/xen/common/grant_table.c
+++ b/xen/common/grant_table.c
@@ -1920,7 +1920,11 @@ int grant_table_init(struct domain *d, int 
max_grant_frames,
     if ( max_grant_frames < INITIAL_NR_GRANT_FRAMES ||
          max_grant_frames > opt_max_grant_frames ||
          max_maptrack_frames > opt_max_maptrack_frames )
+    {
+        dprintk(XENLOG_INFO, "Bad grant table sizes: grant %u, maptrack %u\n",
+                max_grant_frames, max_maptrack_frames);
         return -EINVAL;
+    }
 
     if ( (gt = xzalloc(struct grant_table)) == NULL )
         return -ENOMEM;
-- 
2.11.0