在 2022年06月14日 16:48, Vlastimil Babka 写道:
On 6/14/22 10:39, Ren Yu wrote:
As the possible failure of the kmalloc_slab,
it should be better to check it.
AFAIK failure is not possible, kmalloc_slab() is not an allocation function,
it just returns a member of kmalloc_caches array, which is initialized
elsewhere and shouldn't contain NULLs. So the patch seems unnecessary to me.
Signed-off-by: Ren Yu <renyu@xxxxxxxxxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx>
---
v2:
- fix build waring integer from pointer without a cast
---
---
mm/slab.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/mm/slab.c b/mm/slab.c
index f8cd00f4ba13..72135e555827 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2064,6 +2064,8 @@ int __kmem_cache_create(struct kmem_cache *cachep, slab_flags_t flags)
if (OFF_SLAB(cachep)) {
cachep->freelist_cache =
kmalloc_slab(cachep->freelist_size, 0u);
+ if (unlikely(ZERO_OR_NULL_PTR(cachep->freelist_cache)))
The usual way is "if (!cachep->freelist_cache)". Not sure why check for ZERO.
+ return cachep->freelist_cache;
So in case of NULL this would return NULL, thus 0, but __kmem_cache_create()
return 0 on success, so it's wrong. You would have to return e.g. -ENOMEM.
Thanks for the advice ,I'll be re-patching
}
err = setup_cpu_cache(cachep, gfp);
