From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49340) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1c6zGt-0002q0-I3 for qemu-devel@nongnu.org; Wed, 16 Nov 2016 07:25:00 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1c6zGq-00032p-Bv for qemu-devel@nongnu.org; Wed, 16 Nov 2016 07:24:59 -0500 Date: Wed, 16 Nov 2016 12:24:50 +0000 From: "Dr. David Alan Gilbert" Message-ID: <20161116122450.GC2050@work-vm> References: <1479285571-28145-1-git-send-email-thuth@redhat.com> <20161116131321.35d58700@bahia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161116131321.35d58700@bahia> Subject: Re: [Qemu-devel] [PATCH] tests/postcopy: Use KVM on ppc64 only if it is KVM-HV List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Greg Kurz Cc: Thomas Huth , David Gibson , qemu-ppc@nongnu.org, Laurent Vivier , Stefan Hajnoczi , qemu-devel@nongnu.org, Andrea Arcangeli , Eric Blake * Greg Kurz (groug@kaod.org) wrote: > On Wed, 16 Nov 2016 09:39:31 +0100 > Thomas Huth wrote: > > > The ppc64 postcopy test does not work with KVM-PR, and it is also > > causing annoying warning messages when run on a x86 host. So let's > > use KVM here only if we know that we're running with KVM-HV (which > > automatically also means that we're running on a ppc64 host), and > > fall back to TCG otherwise. > > > > This patch addresses two issues actually: > - the annoying warning when running on a ppc64 guest on a non-ppc64 host > - the fact that KVM-PR seems to be currently broken > > I agree that the former makes sense, but what about the case of running > a x86 guest on a non-x86 host ? > > I'm still feeling uncomfortable with the KVM-PR case... is this a workaround > we want to keep until we find out what's going on or are we starting to > partially deprecate KVM PR ? In any case, I guess we should document this > and probably print some meaningful error message. This is certainly a work around for now, it doesn't suggest anything about deprecation. Dave > > Signed-off-by: Thomas Huth > > --- > > tests/postcopy-test.c | 12 ++++++++---- > > 1 file changed, 8 insertions(+), 4 deletions(-) > > > > diff --git a/tests/postcopy-test.c b/tests/postcopy-test.c > > index d6613c5..dafe8be 100644 > > --- a/tests/postcopy-test.c > > +++ b/tests/postcopy-test.c > > @@ -380,17 +380,21 @@ static void test_migrate(void) > > " -incoming %s", > > tmpfs, bootpath, uri); > > } else if (strcmp(arch, "ppc64") == 0) { > > + const char *accel; > > + > > + /* On ppc64, the test only works with kvm-hv, but not with kvm-pr */ > > + accel = access("/sys/module/kvm_hv", F_OK) ? "tcg" : "kvm:tcg"; > > init_bootfile_ppc(bootpath); > > - cmd_src = g_strdup_printf("-machine accel=kvm:tcg -m 256M" > > + cmd_src = g_strdup_printf("-machine accel=%s -m 256M" > > " -name pcsource,debug-threads=on" > > " -serial file:%s/src_serial" > > " -drive file=%s,if=pflash,format=raw", > > - tmpfs, bootpath); > > - cmd_dst = g_strdup_printf("-machine accel=kvm:tcg -m 256M" > > + accel, tmpfs, bootpath); > > + cmd_dst = g_strdup_printf("-machine accel=%s -m 256M" > > " -name pcdest,debug-threads=on" > > " -serial file:%s/dest_serial" > > " -incoming %s", > > - tmpfs, uri); > > + accel, tmpfs, uri); > > } else { > > g_assert_not_reached(); > > } > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK