[libvirt] [PATCH] qemu: Format gic-version=2 on the command line

[Andrea Bolognani]

On Wed, 2018-04-11 at 08:52 -0400, John Ferlan wrote:
> On 05/03/2018 08:57 AM, Andrea Bolognani wrote:
> > Up until now we have only formatted non-default GIC versions on
> > the command line, in order to maintain compatibility with older
> > QEMU versions that didn't implement the gic-version option to
> > begin with; however, doing so is entirely unnecessary for newer
> > QEMU versions, where the option is available. Moreover, having
> > the GIC version formatted on the command line at all times
> > ensures that QEMU changing its own defaults doesn't affect the
> > ABI of libvirt guests.
> > 
> > A few test cases are removed to avoid extra churn. It doesn't
> > matter for coverage, as those scenarios are already covered by
> > other parts of the test suite.
> > 
> > This patch is better viewed with 'git show -w'.
> > 
> > Signed-off-by: Andrea Bolognani <abologna at redhat.com>
> > ---
> >  src/qemu/qemu_command.c                          | 44 +++++++++++++++++-------
> >  tests/qemuxml2argvdata/aarch64-gic-none-tcg.args |  2 +-
> >  tests/qemuxml2argvdata/aarch64-gic-v2.args       |  2 +-
> >  tests/qemuxml2argvtest.c                         |  6 ----
> >  4 files changed, 33 insertions(+), 21 deletions(-)
> 
> And because of code in qemuDomainDefEnableDefaultFeatures related to TCG
> and GIC and (it seems) bz1414081, the default for TCG would then be v2,
> hence the reason for the none-tcg change, if I'm reading correctly at
> least...  Although perhaps not obvious just reading this patch ;-)

Yes, that is correct. We're merely making the configuration
explicit on the command line, the guest ABI won't change one bit.

-- 
Andrea Bolognani / Red Hat / Virtualization