Re: [PATCH 3/5] mm: Add kmalloc NULL tests

Jörn Engel
2009-07-30T18:35:59Z

On Thu, 30 July 2009 17:36:58 +0200, Johannes Weiner wrote:
> On Thu, Jul 30, 2009 at 04:10:22PM +0200, Julia Lawall wrote:
>
> > diff --git a/mm/slab.c b/mm/slab.c
> > index 7b5d4de..972e427 100644
> > --- a/mm/slab.c
> > +++ b/mm/slab.c
> > @@ -1502,6 +1502,7 @@ void __init kmem_cache_init(void)
> >
> > ptr = kmalloc(sizeof(struct arraycache_init), GFP_NOWAIT);
> >
> > + BUG_ON(!ptr);
> > BUG_ON(cpu_cache_get(&cache_cache) != &initarray_cache.cache);
> > memcpy(ptr, cpu_cache_get(&cache_cache),
> > sizeof(struct arraycache_init));
>
> This does not change the end result when the allocation fails: you get
> a stacktrace and a kernel panic. Leaving it as is saves a line of
> code.

According to http://lwn.net/Articles/342420/, there may be a subtle
difference.

JÃ¶rn

--
"Error protection by error detection and correction."
-- from a university class