[meta-virtualization] [PATCH] xen: patch to fix ARM libxc missing variable init

[Alistair Francis]

On Sun, Sep 17, 2017 at 6:22 PM,  <christopher.w.clark at gmail.com> wrote:
> From: Christopher Clark <christopher.w.clark at gmail.com>
>
> Fix Xen 4.9.0 build error on ARM architecture with gcc 7:
> Import upstream Xen patch 88bfbf90e35f1213f9967a97dee0b2039f9998a4
>
> Error was:
> xc_dom_arm.c:229:31: error: 'domctl.u.address_size.size' may be used
> uninitialized in this function [-Werror=maybe-uninitialized]
>
> Signed-off-by: Christopher Clark <christopher.clark6 at baesystems.com>

Reviewed-by: Alistair Francis <alistair.francis at xilinx.com>
Tested-by: Alistair Francis <alistair.francis at xilinx.com>

Thanks,
Alistair

> ---
>
> This patch has been requested for inclusion in the upstream 4.9 branch
> and later Xen 4.9 releases.
>
> Please use my gmail address for any correspondence.
>
>  ...x-libxc-xc_dom_arm-missing-initialization.patch | 36 ++++++++++++++++++++++
>  recipes-extended/xen/xen_4.9.0.bb                  |  2 ++
>  2 files changed, 38 insertions(+)
>  create mode 100644 recipes-extended/xen/files/fix-libxc-xc_dom_arm-missing-initialization.patch
>
> diff --git a/recipes-extended/xen/files/fix-libxc-xc_dom_arm-missing-initialization.patch b/recipes-extended/xen/files/fix-libxc-xc_dom_arm-missing-initialization.patch
> new file mode 100644
> index 0000000..05016a7
> --- /dev/null
> +++ b/recipes-extended/xen/files/fix-libxc-xc_dom_arm-missing-initialization.patch
> @@ -0,0 +1,36 @@
> +commit 88bfbf90e35f1213f9967a97dee0b2039f9998a4
> +Author: Bernd Kuhls <bernd.kuhls at t-online.de>
> +Date:   Sat Aug 19 16:21:42 2017 +0200
> +
> +    tools/libxc/xc_dom_arm: add missing variable initialization
> +
> +    The variable domctl.u.address_size.size may remain uninitialized if
> +    guest_type is not one of xen-3.0-aarch64 or xen-3.0-armv7l. And the
> +    code precisely checks if this variable is still 0 to decide if the
> +    guest type is supported or not.
> +
> +    This fixes the following build failure with gcc 7.x:
> +
> +    xc_dom_arm.c:229:31: error: 'domctl.u.address_size.size' may be used uninitialized in this function [-Werror=maybe-uninitialized]
> +         if ( domctl.u.address_size.size == 0 )
> +
> +    Patch originally taken from
> +    https://www.mail-archive.com/xen-devel@lists.xen.org/msg109313.html.
> +
> +    Signed-off-by: Bernd Kuhls <bernd.kuhls at t-online.de>
> +    Signed-off-by: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
> +    Acked-by: Wei Liu <wei.liu2 at citrix.com>
> +
> +diff --git a/tools/libxc/xc_dom_arm.c b/tools/libxc/xc_dom_arm.c
> +index e7d4bd0..e669fb0 100644
> +--- a/tools/libxc/xc_dom_arm.c
> ++++ b/tools/libxc/xc_dom_arm.c
> +@@ -223,6 +223,8 @@ static int set_mode(xc_interface *xch, domid_t domid, char *guest_type)
> +
> +     domctl.domain = domid;
> +     domctl.cmd    = XEN_DOMCTL_set_address_size;
> ++    domctl.u.address_size.size = 0;
> ++
> +     for ( i = 0; i < ARRAY_SIZE(types); i++ )
> +         if ( !strcmp(types[i].guest, guest_type) )
> +             domctl.u.address_size.size = types[i].size;
> diff --git a/recipes-extended/xen/xen_4.9.0.bb b/recipes-extended/xen/xen_4.9.0.bb
> index 0b20936..8e9c802 100644
> --- a/recipes-extended/xen/xen_4.9.0.bb
> +++ b/recipes-extended/xen/xen_4.9.0.bb
> @@ -1,7 +1,9 @@
> +FILESEXTRAPATHS_prepend := "${THISDIR}/files:"
>  require xen.inc
>
>  SRC_URI = " \
>      https://downloads.xenproject.org/release/xen/${PV}/xen-${PV}.tar.gz \
> +    file://fix-libxc-xc_dom_arm-missing-initialization.patch \
>      "
>
>  SRC_URI[md5sum] = "f0a753637630f982dfbdb64121fd71e1"
> --
> 2.7.4
>