mm/cma.c: fix crash on CMA allocation if bitmap allocation fails

[ Upstream commit 1df3a339074e31db95c4790ea9236874b13ccd87 ]

f022d8cb7ec7 ("mm: cma: Don't crash on allocation if CMA area can't be
activated") fixes the crash issue when activation fails via setting
cma->count as 0, same logic exists if bitmap allocation fails.

Link: http://lkml.kernel.org/r/20190325081309.6004-1-zbestahu@gmail.com
Signed-off-by: Yue Hu <huyue2@yulong.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/mm/cma.c b/mm/cma.c
index b5d8847..4ea0f32 100644 (file)
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -100,8 +100,10 @@ static int __init cma_activate_area(struct cma *cma)
 
        cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
 
-       if (!cma->bitmap)
+       if (!cma->bitmap) {
+               cma->count = 0;
                return -ENOMEM;
+       }
 
        WARN_ON_ONCE(!pfn_valid(pfn));
        zone = page_zone(pfn_to_page(pfn));