1 files changed, 8 insertions, 1 deletions

diff --git a/lib/idr.c b/lib/idr.c
index 648239079dd2..ca5aa000d6c3 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -625,7 +625,14 @@ void *idr_get_next(struct idr *idp, int *nextidp)
                         return p;
                 }
 
-                id += 1 << n;
+                /*
+                 * Proceed to the next layer at the current level.  Unlike
+                 * idr_for_each(), @id isn't guaranteed to be aligned to
+                 * layer boundary at this point and adding 1 << n may
+                 * incorrectly skip IDs.  Make sure we jump to the
+                 * beginning of the next layer using round_up().
+                 */
+                id = round_up(id + 1, 1 << n);
                 while (n < fls(id)) {
                         n += IDR_BITS;
                         p = *--paa;