[PATCH] Catch kmalloc failure in kmem_cache_init() (was: [QUESTION] check for mem in slab)

[Johannes Weiner]

Hi,

> On 3/30/07, Heiko Carstens <heiko.carstens@xxxxxxxxxx> wrote:
> >> in file mm/slab.c and routine kmem_cache_init() I found there
> >> is no checking for allocated memory on line:
> >>
> >>       /* 4) Replace the bootstrap head arrays */
> >>       {
> >>               struct array_cache *ptr;
> >>
> >>               ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL);
> >>
> >> --> no check for ptr == NULL <--
> >[...]
> >> is that OK? or it's a bug?
> >
> >It's ok. If that allocation fails your machine won't come up anyway.
> 
> We ought to add a BUG_ON or comment at least there as this keeps
> popping up again and again.

Done. Patch attached.

Signed-off-by: Johannes Weiner <hannes-kernel@xxxxxxxxxxxx>

diff --git a/mm/slab.c b/mm/slab.c
index 57f7aa4..6d7e486 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1512,6 +1512,7 @@ void __init kmem_cache_init(void)
 		struct array_cache *ptr;
 
 		ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL);
+		BUG_ON(!ptr);
 
 		local_irq_disable();
 		BUG_ON(cpu_cache_get(&cache_cache) != &initarray_cache.cache);
@@ -1526,6 +1527,7 @@ void __init kmem_cache_init(void)
 		local_irq_enable();
 
 		ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL);
+		BUG_ON(!ptr);
 
 		local_irq_disable();
 		BUG_ON(cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep)