[PATCH AUTOSEL 4.14 015/123] mm/cma.c: cma_declare_contiguous: correct err handling

Sasha Levin
2019-03-27T18:17:11Z

From: Peng Fan <peng.fan@nxp.com>

[ Upstream commit 0d3bd18a5efd66097ef58622b898d3139790aa9d ]

In case cma_init_reserved_mem failed, need to free the memblock
allocated by memblock_reserve or memblock_alloc_range.

Quote Catalin's comments:
https://lkml.org/lkml/2019/2/26/482

Kmemleak is supposed to work with the memblock_{alloc,free} pair and it
ignores the memblock_reserve() as a memblock_alloc() implementation
detail. It is, however, tolerant to memblock_free() being called on
a sub-range or just a different range from a previous memblock_alloc().
So the original patch looks fine to me. FWIW:

Link: http://lkml.kernel.org/r/20190227144631.16708-1-peng.fan@nxp.com
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
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>
---
mm/cma.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/mm/cma.c b/mm/cma.c
index 022e52bd8370..5749c9b3b5d0 100644
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -348,12 +348,14 @@ int __init cma_declare_contiguous(phys_addr_t base,

ret = cma_init_reserved_mem(base, size, order_per_bit, name, res_cma);
if (ret)
- goto err;
+ goto free_mem;

pr_info("Reserved %ld MiB at %pa\n", (unsigned long)size / SZ_1M,
&base);
return 0;

+free_mem:
+ memblock_free(base, size);
err:
pr_err("Failed to reserve %ld MiB\n", (unsigned long)size / SZ_1M);
return ret;
--
2.19.1