Re: [PATCH v2 3/3] tools: disable building qemu-trad per default

[Samuel Thibault <samuel.thibault@xxxxxxxxxxxx>]

Juergen Gross, le jeu. 09 sept. 2021 14:49:24 +0200, a ecrit:
> Using qemu-traditional as device model is deprecated for some time now.
> 
> So change the default for building it to "disable". This will affect
> ioemu-stubdom, too, as there is a direct dependency between the two.
> 
> Today it is possible to use a PVH/HVM Linux-based stubdom as device
> model. Additionally using ioemu-stubdom isn't really helping for
> security, as it requires to run a very old and potentially buggy qemu
> version in a PV domain. This is adding probably more security problems
> than it is removing by using a stubdom.
> 
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>

Reviewed-by: Samuel Thibault <samuel.thibault@xxxxxxxxxxxx>

> ---
> V2:
> - new patch
> ---
>  CHANGELOG.md         |  3 +++
>  stubdom/configure    |  8 --------
>  stubdom/configure.ac |  8 +-------
>  tools/configure      | 17 ++---------------
>  tools/configure.ac   | 13 +------------
>  5 files changed, 7 insertions(+), 42 deletions(-)
> 
> diff --git a/CHANGELOG.md b/CHANGELOG.md
> index e7107ac3de..e5ab49e779 100644
> --- a/CHANGELOG.md
> +++ b/CHANGELOG.md
> @@ -18,6 +18,9 @@ The format is based on [Keep a 
> Changelog](https://keepachangelog.com/en/1.0.0/)
>     or by passing "iommu=quarantine=scratch-page" on the hypervisor command 
> line.
>   - pv-grub stubdoms will no longer be built per default. In order to be able 
> to use pv-grub
>     configure needs to be called with "--enable-pv-grub" as parameter.
> + - qemu-traditional based device models (both, qemu-traditional and 
> ioemu-stubdom) will
> +   no longer be built per default. In order to be able to use those, 
> configure needs to
> +   be called with "--enable-qemu-traditional" as parameter.
>  
>  ## [4.15.0 
> UNRELEASED](https://xenbits.xen.org/gitweb/?p=xen.git;a=shortlog;h=RELEASE-4.15.0)
>  - TBD
>  
> diff --git a/stubdom/configure b/stubdom/configure
> index df31532abb..07b709f998 100755
> --- a/stubdom/configure
> +++ b/stubdom/configure
> @@ -2286,14 +2286,6 @@ fi
>  # Check whether --enable-qemu-traditional was given.
>  if test "${enable_qemu_traditional+set}" = set; then :
>    enableval=$enable_qemu_traditional;
> -else
> -
> -    case "$host_cpu" in
> -        i[3456]86|x86_64)
> -           enable_qemu_traditional="yes";;
> -        *) enable_qemu_traditional="no";;
> -    esac
> -
>  fi
>  
>  if test "x$enable_qemu_traditional" = "xyes"; then :
> diff --git a/stubdom/configure.ac b/stubdom/configure.ac
> index a07a1edae5..e20d99edac 100644
> --- a/stubdom/configure.ac
> +++ b/stubdom/configure.ac
> @@ -27,13 +27,7 @@ AX_STUBDOM_DEFAULT_ENABLE([xenstorepvh-stubdom], 
> [xenstorepvh])
>  AX_STUBDOM_CONDITIONAL([vtpm-stubdom], [vtpm])
>  AX_STUBDOM_CONDITIONAL([vtpmmgr-stubdom], [vtpmmgr])
>  
> -AC_ARG_ENABLE([qemu-traditional],,,[
> -    case "$host_cpu" in
> -        i[[3456]]86|x86_64)
> -           enable_qemu_traditional="yes";;
> -        *) enable_qemu_traditional="no";;
> -    esac
> -])
> +AC_ARG_ENABLE([qemu-traditional])
>  AS_IF([test "x$enable_qemu_traditional" = "xyes"], [
>      qemu_traditional=y],[
>      qemu_traditional=n
> diff --git a/tools/configure b/tools/configure
> index 33814b24b3..8bf8fe75b8 100755
> --- a/tools/configure
> +++ b/tools/configure
> @@ -1502,8 +1502,8 @@ Optional Features:
>    --disable-seabios       Disable SeaBIOS (default is ENABLED)
>    --disable-golang        Disable Go tools (default is ENABLED)
>    --enable-qemu-traditional
> -                          Enable qemu traditional device model, (DEFAULT is 
> on
> -                          for Linux or NetBSD x86, otherwise off)
> +                          Enable qemu traditional device model, (DEFAULT is
> +                          off)
>    --enable-rombios        Enable ROMBIOS, (DEFAULT is on if qemu-traditional
>                            is enabled, otherwise off)
>    --disable-ipxe          Enable in-tree IPXE, (DEFAULT is on if rombios is
> @@ -4287,19 +4287,6 @@ LINUX_BACKEND_MODULES="`eval echo 
> $LINUX_BACKEND_MODULES`"
>  # Check whether --enable-qemu-traditional was given.
>  if test "${enable_qemu_traditional+set}" = set; then :
>    enableval=$enable_qemu_traditional;
> -else
> -
> -    case "$host_cpu" in
> -        i[3456]86|x86_64)
> -           enable_qemu_traditional="yes";;
> -        *) enable_qemu_traditional="no";;
> -    esac
> -    case "$host_os" in
> -        freebsd*)
> -           enable_qemu_traditional="no";;
> -    esac
> -
> -
>  fi
>  
>  if test "x$enable_qemu_traditional" = "xyes"; then :
> diff --git a/tools/configure.ac b/tools/configure.ac
> index 6414fcbb44..a713fd34d6 100644
> --- a/tools/configure.ac
> +++ b/tools/configure.ac
> @@ -120,18 +120,7 @@ AC_SUBST(LINUX_BACKEND_MODULES)
>  
>  AC_ARG_ENABLE([qemu-traditional],
>      AS_HELP_STRING([--enable-qemu-traditional],
> -                   [Enable qemu traditional device model, (DEFAULT is on for 
> Linux or NetBSD x86, otherwise off)]),,[
> -    case "$host_cpu" in
> -        i[[3456]]86|x86_64)
> -           enable_qemu_traditional="yes";;
> -        *) enable_qemu_traditional="no";;
> -    esac
> -    case "$host_os" in
> -        freebsd*)
> -           enable_qemu_traditional="no";;
> -    esac
> -
> -])
> +                   [Enable qemu traditional device model, (DEFAULT is off)]))
>  AS_IF([test "x$enable_qemu_traditional" = "xyes"], [
>  AC_DEFINE([HAVE_QEMU_TRADITIONAL], [1], [Qemu traditional enabled])
>      qemu_traditional=y],[
> -- 
> 2.26.2
> 

-- 
Samuel
<A>  mr  -  remove the home of correct users who accidentally enter mr
<A>        instead of rm