kmalloc size should never exceed KMALLOC_MAX_SIZE. kmalloc_index realise if size is exceed KMALLOC_MAX_SIZE, e.g 64M, kmalloc_index just return index 26, but never check with OS`s max kmalloc config KMALLOC_MAX_SIZE. This index`s kmalloc caches maybe not create in function create_kmalloc_caches. We can throw an warninginfo in kmalloc at the beginning, instead of being guaranteed by the buddy alloc behind. Signed-off-by: Bernard Zhao <bernard@xxxxxxxx> --- include/linux/slab.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/include/linux/slab.h b/include/linux/slab.h index 6d45488..59b60d2 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -351,6 +351,10 @@ static __always_inline unsigned int kmalloc_index(size_t size) if (!size) return 0; + /* size should never exceed KMALLOC_MAX_SIZE. */ + if (size > KMALLOC_MAX_SIZE) + WARN(1, "size exceed max kmalloc size!\n"); + if (size <= KMALLOC_MIN_SIZE) return KMALLOC_SHIFT_LOW; -- 2.7.4
