From: Jens Axboe <axboe@kernel.dk>
Date: Thu, 23 Aug 2018 18:22:10 +0000 (-0600)
Subject: axmap: return early of an overlap results in 0 settable bits
X-Git-Tag: fio-3.9~16
X-Git-Url: https://git.kernel.dk/?p=fio.git;a=commitdiff_plain;h=49e1ade14949b737dbd111b19a4057faf9aa77bb;hp=7ab5b8d29ab4402f921b9d4d9a75d34aa9c69f69

axmap: return early of an overlap results in 0 settable bits

Reported-by: Bart Van Assche <bart.vanassche@wdc.com>
Fixes: 15a4f49 ("lib/axmap: Simplify axmap_set_fn()")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/lib/axmap.c b/lib/axmap.c
index e194e807..03e712f5 100644
--- a/lib/axmap.c
+++ b/lib/axmap.c
@@ -241,6 +241,8 @@ static bool axmap_set_fn(struct axmap_level *al, unsigned long offset,
 
 	if (overlap) {
 		nr_bits = ffz(~overlap) - bit;
+		if (!nr_bits)
+			return true;
 		mask = bit_masks[nr_bits] << bit;
 	}