Re: [PATCH -mm] slab: update_memcg_params: explicitly check that old array != NULL

Dan Carpenter
2015-01-26T15:14:24Z

On Mon, Jan 26, 2015 at 01:45:34PM +0300, Vladimir Davydov wrote:
> On Mon, Jan 26, 2015 at 01:23:05PM +0300, Dan Carpenter wrote:
> > On Mon, Jan 26, 2015 at 01:01:19PM +0300, Vladimir Davydov wrote:
> > > This warning is false-positive, because @old equals NULL iff
> > > @memcg_nr_cache_ids equals 0.
> >
> > I don't see how it could be a false positive. The "old" pointer is
> > dereferenced inside the call to memset() so unless memset is a macro the
> > compiler isn't going to optimize the dereference away.
>
> old->entries is not dereferenced: memcg_cache_array->entries is not a
> pointer - it is embedded to the memcg_cache_array struct.

Ah. Ok. Thanks.

regards,
dan carpenter