Re: [libvirt] [PATCH] qemu: Don't try to parse -help for new QEMU

On 11/12/14 17:09, Jiri Denemark wrote: > Since QEMU 1.2.0, we switched to QMP probing instead of parsing -help > (and other commands, such as -cpu ?) output. However, if QMP probing > failed, we still tried starting QEMU with various options and parsing > the output, which was guaranteed to fail because the output changed. > Let's just refuse parsing -help for QEMU >= 1.2.0. > > https://bugzilla.redhat.com/show_bug.cgi?id=1160318 > Signed-off-by: Jiri Denemark <jdenemar(a)redhat.com&gt; > --- > src/qemu/qemu_capabilities.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c > index 74a3b24..bef96d5 100644 > --- a/src/qemu/qemu_capabilities.c > +++ b/src/qemu/qemu_capabilities.c > @@ -1384,6 +1384,16 @@ int virQEMUCapsParseHelpStr(const char *qemu, > > *version = (major * 1000 * 1000) + (minor * 1000) + micro; > > + /* Refuse to parse -help output for QEMU releases >= 1.2.0 that should be > + * using QMP probing. > + */ > + if (*version > 1002000) { > + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, > + _("QEMU %u.%u.%u is too new for help parsing"), > + major, minor, micro); > + goto cleanup; > + } > + > if (virQEMUCapsComputeCmdFlags(help, *version, *is_kvm, *kvm_version, > qemuCaps, check_yajl) < 0) > goto cleanup; > ACK, although I think that one of the steps that lead to fixing the issue for the reporter was to purge the caps cache. As I've heard/seen that happening we might want to check the code that checks the validity of the cache.