[PATCH 2] mm/kvmalloc: do not call kmalloc for size > KMALLOC_MAX_SIZE

Konstantin Khlebnikov
2018-11-01T10:09:25Z

Allocations over KMALLOC_MAX_SIZE could be served only by vmalloc.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
---
mm/util.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/mm/util.c b/mm/util.c
index 8bf08b5b5760..f5f04fa22814 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -392,6 +392,9 @@ void *kvmalloc_node(size_t size, gfp_t flags, int node)
gfp_t kmalloc_flags = flags;
void *ret;

+ if (size > KMALLOC_MAX_SIZE)
+ goto fallback;
+
/*
* vmalloc uses GFP_KERNEL for some internal allocations (e.g page tables)
* so the given set of flags has to be compatible.
@@ -422,6 +425,7 @@ void *kvmalloc_node(size_t size, gfp_t flags, int node)
if (ret || size <= PAGE_SIZE)
return ret;

+fallback:
return __vmalloc_node_flags_caller(size, node, flags,
__builtin_return_address(0));
}