On 05.11.2018 16:03, Vlastimil Babka wrote:
On 11/1/18 11:09 AM, Konstantin Khlebnikov wrote:
Allocations over KMALLOC_MAX_SIZE could be served only by vmalloc.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
Makes sense regardless of warnings stuff.
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
But it must be moved below the GFP_KERNEL check!
But kmalloc cannot handle it regardless of GFP.
Ok maybe write something like this
if (size > KMALLOC_MAX_SIZE) {
if (WARN_ON_ONCE((flags & GFP_KERNEL) != GFP_KERNEL)
return NULL;
goto do_vmalloc;
}
or fix that uncertainty right in vmalloc
For now comment in vmalloc declares
* Any use of gfp flags outside of GFP_KERNEL should be consulted
* with mm people.
=)
---
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));
}
