On 2018/9/26 21:58, Christophe LEROY wrote:

Le 26/09/2018 à 13:46, zhong jiang a écrit :

quoted

It is safe to move dereference below a NULL test.

Signed-off-by: zhong jiang <redacted>
---
  arch/powerpc/kernel/cacheinfo.c | 5 ++---
  1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kernel/cacheinfo.c b/arch/powerpc/kernel/cacheinfo.c
index a8f20e5..7f19714 100644
--- a/arch/powerpc/kernel/cacheinfo.c
+++ b/arch/powerpc/kernel/cacheinfo.c

@@ -401,14 +401,13 @@ static struct cache *cache_lookup_or_instantiate(struct device_node *node,
      struct cache *cache;
        cache = cache_lookup_by_node(node);
+    if (!cache)
+        cache = cache_do_one_devnode(node, level);

But by doing this, you change the meaning of the following warning. Is that what you want ? In that case the text of the WARN_ONCE() should be changed, because the mismatch is not only on lookup now.

Yep, I forget the WARN_ONCE. I think we should just remove it. Thought?

Thanks,
zhong jiang

Christophe

quoted

        WARN_ONCE(cache && cache->level != level,
            "cache level mismatch on lookup (got %d, expected %d)\n",
            cache->level, level);
  -    if (!cache)
-        cache = cache_do_one_devnode(node, level);
-
      return cache;
  }
 

.