zbud_alloc() incorrectly verifies the size of allocation limit. It should deny the allocation request greater than (PAGE_SIZE - ZHDR_SIZE_ALIGNED - CHUNK_SIZE), not (PAGE_SIZE - ZHDR_SIZE_ALIGNED) which has no remaining spaces for its buddy. There is no point in spending the entire zbud page storing only a single page, since we don't have any benefits.
Signed-off-by: Heesub Shin <heesub.s...@samsung.com> --- mm/zbud.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/zbud.c b/mm/zbud.c index 9bb4710..ad1e781 100644 --- a/mm/zbud.c +++ b/mm/zbud.c @@ -257,7 +257,7 @@ int zbud_alloc(struct zbud_pool *pool, int size, gfp_t gfp, if (size <= 0 || gfp & __GFP_HIGHMEM) return -EINVAL; - if (size > PAGE_SIZE - ZHDR_SIZE_ALIGNED) + if (size > PAGE_SIZE - ZHDR_SIZE_ALIGNED - CHUNK_SIZE) return -ENOSPC; chunks = size_to_chunks(size); spin_lock(&pool->lock); -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/