The irqdomain code was checking for 0 or 1 entries, not 0 entries like the comment said they were. Introduce a new helper that will actually check for an empty tree. Signed-off-by: Matthew Wilcox <willy@xxxxxxxxxxxxxxx> Reviewed-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx> --- include/linux/radix-tree.h | 5 +++++ kernel/irq/irqdomain.c | 7 +------ 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h index 51a97ac8bfbf..83f708e5db59 100644 --- a/include/linux/radix-tree.h +++ b/include/linux/radix-tree.h @@ -136,6 +136,11 @@ do { \ (root)->rnode = NULL; \ } while (0) +static inline bool radix_tree_empty(struct radix_tree_root *root) +{ + return root->rnode == NULL; +} + /** * Radix-tree synchronization * diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 3a519a01118b..ba3f60d8df2f 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -139,12 +139,7 @@ void irq_domain_remove(struct irq_domain *domain) { mutex_lock(&irq_domain_mutex); - /* - * radix_tree_delete() takes care of destroying the root - * node when all entries are removed. Shout if there are - * any mappings left. - */ - WARN_ON(domain->revmap_tree.height); + WARN_ON(!radix_tree_empty(&domain->revmap_tree)); list_del(&domain->link); -- 2.8.0.rc3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>