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Message-ID: <1481091951.4092.12.camel@sipsolutions.net>
Subject: Re: [PATCH 10/10] virtio: enable endian checks for sparse builds
From: Johannes Berg <johannes@sipsolutions.net>
To: "Michael S. Tsirkin" <mst@redhat.com>, linux-kernel@vger.kernel.org
Cc: Jason Wang <jasowang@redhat.com>, linux-kbuild@vger.kernel.org,
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Date: Wed, 07 Dec 2016 07:25:51 +0100
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On Tue, 2016-12-06 at 17:41 +0200, Michael S. Tsirkin wrote:

> It seems that there should be a better way to do it,
> but this works too.

In some cases there might be:

> --- a/drivers/s390/virtio/Makefile
> +++ b/drivers/s390/virtio/Makefile
> @@ -6,6 +6,8 @@
>  # it under the terms of the GNU General Public License (version 2
> only)
>  # as published by the Free Software Foundation.
>  
> +CFLAGS_virtio_ccw.o += -D__CHECK_ENDIAN__
> +CFLAGS_kvm_virtio.o += -D__CHECK_ENDIAN__
>  s390-virtio-objs := virtio_ccw.o
>  ifdef CONFIG_S390_GUEST_OLD_TRANSPORT
>  s390-virtio-objs += kvm_virtio.o

Here you could use

ccflags-y += -D__CHECK_ENDIAN__

for example, or even

subdir-ccflags-y += -D__CHECK_ENDIAN__

(in case any subdirs ever get added here)

> --- a/drivers/vhost/Makefile
> +++ b/drivers/vhost/Makefile
> @@ -1,3 +1,4 @@
> +ccflags-y := -D__CHECK_ENDIAN__

Looks like you did that here and in some other places though - so
perhaps the s390 one was intentionally different?

> --- a/net/packet/Makefile
> +++ b/net/packet/Makefile
> @@ -2,6 +2,7 @@
>  # Makefile for the packet AF.
>  #
>  
> +ccflags-y := -D__CHECK_ENDIAN__

Technically this is slightly more than advertised, but I guess that
still makes sense if it's clean now.

johannes