diff options
Diffstat (limited to 'drivers/xen/balloon.c')
| -rw-r--r-- | drivers/xen/balloon.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c index dc4305b407bf..7c8a2cf16f58 100644 --- a/drivers/xen/balloon.c +++ b/drivers/xen/balloon.c @@ -338,7 +338,16 @@ static enum bp_state reserve_additional_memory(void) } #endif - rc = add_memory_resource(nid, resource); + /* + * add_memory_resource() will call online_pages() which in its turn + * will call xen_online_page() callback causing deadlock if we don't + * release balloon_mutex here. Unlocking here is safe because the + * callers drop the mutex before trying again. + */ + mutex_unlock(&balloon_mutex); + rc = add_memory_resource(nid, resource, memhp_auto_online); + mutex_lock(&balloon_mutex); + if (rc) { pr_warn("Cannot add additional memory (%i)\n", rc); goto err; |