From f0fd50504a54f5548eb666dc16ddf8394e44e4b7 Mon Sep 17 00:00:00 2001 From: Yue Hu Date: Mon, 13 May 2019 17:16:37 -0700 Subject: [PATCH] mm/cma_debug.c: fix the break condition in cma_maxchunk_get() If not find zero bit in find_next_zero_bit(), it will return the size parameter passed in, so the start bit should be compared with bitmap_maxno rather than cma->count. Although getting maxchunk is working fine due to zero value of order_per_bit currently, the operation will be stuck if order_per_bit is set as non-zero. Link: http://lkml.kernel.org/r/20190319092734.276-1-zbestahu@gmail.com Signed-off-by: Yue Hu Reviewed-by: Andrew Morton Cc: Michal Hocko Cc: Joe Perches Cc: David Rientjes Cc: Dmitry Safonov Cc: Joonsoo Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/cma_debug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/cma_debug.c b/mm/cma_debug.c index 8d7b2fd52225..a7dd9e8e10d5 100644 --- a/mm/cma_debug.c +++ b/mm/cma_debug.c @@ -56,7 +56,7 @@ static int cma_maxchunk_get(void *data, u64 *val) mutex_lock(&cma->lock); for (;;) { start = find_next_zero_bit(cma->bitmap, bitmap_maxno, end); - if (start >= cma->count) + if (start >= bitmap_maxno) break; end = find_next_bit(cma->bitmap, bitmap_maxno, start); maxchunk = max(end - start, maxchunk);