On Mon, Jan 30, 2017 at 10:49:36AM +0100, Michal Hocko wrote:
> From: Michal Hocko <mhocko@suse.com>
>
> There are many code paths opencoding kvmalloc. Let's use the helper
> instead. The main difference to kvmalloc is that those users are usually
> not considering all the aspects of the memory allocator. E.g. allocation
> requests <= 32kB (with 4kB pages) are basically never failing and invoke
> OOM killer to satisfy the allocation. This sounds too disruptive for
> something that has a reasonable fallback - the vmalloc. On the other
> hand those requests might fallback to vmalloc even when the memory
> allocator would succeed after several more reclaim/compaction attempts
> previously. There is no guarantee something like that happens though.
>
> This patch converts many of those places to kv[mz]alloc* helpers because
> they are more conservative.
>
> Changes since v1
> - add kvmalloc_array - this might silently fix some overflow issues
>   because most users simply didn't check the overflow for the vmalloc
>   fallback.
>
> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
> Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
> Cc: Herbert Xu <herbert@gondor.apana.org.au>
> Cc: Anton Vorontsov <anton@enomsg.org>
> Cc: Colin Cross <ccross@android.com>
> Cc: Kees Cook <keescook@chromium.org>
> Cc: Tony Luck <tony.luck@intel.com>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: Ben Skeggs <bskeggs@redhat.com>
> Cc: Kent Overstreet <kent.overstreet@gmail.com>
> Cc: Santosh Raspatur <santosh@chelsio.com>
> Cc: Hariprasad S <hariprasad@chelsio.com>
> Cc: Yishai Hadas <yishaih@mellanox.com>
> Cc: Oleg Drokin <oleg.drokin@intel.com>
> Cc: "Yan, Zheng" <zyan@redhat.com>
> Cc: Alexander Viro <viro@zeniv.linux.org.uk>
> Cc: Alexei Starovoitov <ast@kernel.org>
> Cc: Eric Dumazet <eric.dumazet@gmail.com>
> Cc: netdev@vger.kernel.org
> Acked-by: Andreas Dilger <andreas.dilger@intel.com> # Lustre
> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> # Xen bits
> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> # KVM/s390
> Acked-by: Dan Williams <dan.j.williams@intel.com> # nvdim
> Acked-by: David Sterba <dsterba@suse.com> # btrfs
> Acked-by: Ilya Dryomov <idryomov@gmail.com> # Ceph
> Acked-by: Tariq Toukan <tariqt@mellanox.com> # mlx4
> Signed-off-by: Michal Hocko <mhocko@suse.com>

Acked-by: Leon Romanovsky <leonro@mellanox.com> # mlx5