On 08.04.2015 17:25, Cole Robinson wrote:
On 04/08/2015 11:12 AM, Michal Privoznik wrote:
https://bugzilla.redhat.com/show_bug.cgi?id=1209948
So we have this bug. The virConnectGetDomainCapabilities() API performs a couple of checks before it produces any result. One of the checks is if the architecture requested by user can be run by the binary (again user provided). However, the check is pretty dumb. It merely compares if the default binary architecture matches the one provided by user. However, a qemu binary can run multiple architectures. For instance: qemu-system-ppc64 can run: ppc, ppcle, ppc64, ppc64le and ppcemb. The default is ppc64, so if user requested something else, like ppc64le, the check would have failed without obvious reason.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- src/qemu/qemu_driver.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 921417c..d217481 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -18788,7 +18788,10 @@ qemuConnectGetDomainCapabilities(virConnectPtr conn, arch_from_caps = virQEMUCapsGetArch(qemuCaps);
if (arch_from_caps != arch && - (arch_from_caps != VIR_ARCH_X86_64 || arch != VIR_ARCH_I686)) { + !((ARCH_IS_X86(arch) && ARCH_IS_X86(arch_from_caps)) || + (ARCH_IS_PPC(arch) && ARCH_IS_PPC(arch_from_caps)) || + (ARCH_IS_ARM(arch) && ARCH_IS_ARM(arch_from_caps)) || + (ARCH_IS_S390(arch) && ARCH_IS_S390(arch_from_caps)))) { virReportError(VIR_ERR_INVALID_ARG, _("architecture from emulator '%s' doesn't " "match given architecture '%s'"),
As I mentioned in the bug, really I think this is more a problem of the virQEMUCapsCacheLookup* interface. Nowadays we can have the same emulatorbin map to multiple architectures, and the same architecture provided by multiple emulators, so CacheLookup* functions that search for only the specified emulator or only the specified arch are just going to breed more bugs like this.
While I understand your concern, qemu is not helping. It is not exporting list of supported architectures for given binary. What I've found is: a) we use 'query-target' command to determine the target architecture for the binary. However, this returns only the default architecture, not a list of all supported architectures. b) There exists 'qemu-system-* -cpu ?', which outputs something like this: x86 athlon QEMU Virtual CPU version 2.2.92 x86 Broadwell Intel Core Processor (Broadwell) The first item looks like an arch. But it's not much of a help either. For example for qemu-system-{i386,x86_64} I get the very same list of supported CPUs. And architectures too. But if I query those two binaries on QMP for their target they produce different results: 'i386' and 'x86_64'. While I agree your approach is better, there's not much we can do unless qemu is more helping. So I see two options: 1) ask qemu devels 2) merge this meanwhile Michal