From: Li Zhang <zhlcindy(a)linux.vnet.ibm.com&gt; For QEMU2.0 forward version, it supports PCI multiBUS. Currently, libvirt still disables it which causes an error "Bus 'pci' not found". Signed-off-by: Li Zhang <zhlcindy(a)linux.vnet.ibm.com&gt; --- src/qemu/qemu_capabilities.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c index 2c8ec10..b49398f 100644 --- a/src/qemu/qemu_capabilities.c +++ b/src/qemu/qemu_capabilities.c @@ -3019,6 +3019,9 @@ virQEMUCapsInitQMPMonitor(virQEMUCapsPtr qemuCaps, if (qemuCaps->version >= 1006000) virQEMUCapsSet(qemuCaps, QEMU_CAPS_DEVICE_VIDEO_PRIMARY); + if (qemuCaps->version >= 2000000) + virQEMUCapsSet(qemuCaps, QEMU_CAPS_PCI_MULTIBUS); +

On 2014年04月09日 11:20, Eric Blake wrote: > On 04/08/2014 08:03 PM, Li Zhang wrote: >> From: Li Zhang <zhlcindy(a)linux.vnet.ibm.com&gt; >> >> For QEMU2.0 forward version, it supports PCI multiBUS. >> Currently, libvirt still disables it which causes an error >> "Bus 'pci' not found". >> >> Signed-off-by: Li Zhang <zhlcindy(a)linux.vnet.ibm.com&gt; >> --- >> src/qemu/qemu_capabilities.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c >> index 2c8ec10..b49398f 100644 >> --- a/src/qemu/qemu_capabilities.c >> +++ b/src/qemu/qemu_capabilities.c >> @@ -3019,6 +3019,9 @@ virQEMUCapsInitQMPMonitor(virQEMUCapsPtr qemuCaps, >> if (qemuCaps->version >= 1006000) >> virQEMUCapsSet(qemuCaps, QEMU_CAPS_DEVICE_VIDEO_PRIMARY); >> + if (qemuCaps->version >= 2000000) >> + virQEMUCapsSet(qemuCaps, QEMU_CAPS_PCI_MULTIBUS); >> + > This is a version number check, which is bad. Is there a QMP command we > can issue that gives a more reliable answer of whether the feature is > present? > Hi Eric, I can't find any QMP command for MULTIBUS in QEMU. There is only one "query-pci" to list PCI bus and devices information.

On 09.04.2014 04:03, Li Zhang wrote: > From: Li Zhang <zhlcindy(a)linux.vnet.ibm.com&gt; > > For QEMU2.0 forward version, it supports PCI multiBUS. > Currently, libvirt still disables it which causes an error > "Bus 'pci' not found". > > Signed-off-by: Li Zhang <zhlcindy(a)linux.vnet.ibm.com&gt; > --- > src/qemu/qemu_capabilities.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c > index 2c8ec10..b49398f 100644 > --- a/src/qemu/qemu_capabilities.c > +++ b/src/qemu/qemu_capabilities.c > @@ -3019,6 +3019,9 @@ virQEMUCapsInitQMPMonitor(virQEMUCapsPtr qemuCaps, > if (qemuCaps->version >= 1006000) > virQEMUCapsSet(qemuCaps, QEMU_CAPS_DEVICE_VIDEO_PRIMARY); > > + if (qemuCaps->version >= 2000000) > + virQEMUCapsSet(qemuCaps, QEMU_CAPS_PCI_MULTIBUS); > + > if (virQEMUCapsProbeQMPCommands(qemuCaps, mon) < 0) > goto cleanup; > if (virQEMUCapsProbeQMPEvents(qemuCaps, mon) < 0) > Libvirt is setting this capability unconditionally for all x86_64 and i686 (see virQEMUCapsInitArchQMPBasic). What is the actual scenario you're seeing this error in?

Michal

On 10.04.2014 07:26, Li Zhang wrote: > On 2014年04月09日 17:25, Michal Privoznik wrote: >> On 09.04.2014 04:03, Li Zhang wrote: >>> From: Li Zhang <zhlcindy(a)linux.vnet.ibm.com&gt; >>> >>> For QEMU2.0 forward version, it supports PCI multiBUS. >>> Currently, libvirt still disables it which causes an error >>> "Bus 'pci' not found". >>> >>> Signed-off-by: Li Zhang <zhlcindy(a)linux.vnet.ibm.com&gt; >>> --- >>> src/qemu/qemu_capabilities.c | 3 +++ >>> 1 file changed, 3 insertions(+) >>> >>> diff --git a/src/qemu/qemu_capabilities.c >>> b/src/qemu/qemu_capabilities.c >>> index 2c8ec10..b49398f 100644 >>> --- a/src/qemu/qemu_capabilities.c >>> +++ b/src/qemu/qemu_capabilities.c >>> @@ -3019,6 +3019,9 @@ virQEMUCapsInitQMPMonitor(virQEMUCapsPtr >>> qemuCaps, >>> if (qemuCaps->version >= 1006000) >>> virQEMUCapsSet(qemuCaps, QEMU_CAPS_DEVICE_VIDEO_PRIMARY); >>> >>> + if (qemuCaps->version >= 2000000) >>> + virQEMUCapsSet(qemuCaps, QEMU_CAPS_PCI_MULTIBUS); >>> + >>> if (virQEMUCapsProbeQMPCommands(qemuCaps, mon) < 0) >>> goto cleanup; >>> if (virQEMUCapsProbeQMPEvents(qemuCaps, mon) < 0) >>> >> >> Libvirt is setting this capability unconditionally for all x86_64 and >> i686 (see virQEMUCapsInitArchQMPBasic). What is the actual scenario >> you're seeing this error in? > > For pseries machine, before QEMU2.0, the PCI bus default name is always > "pci". > QEMU2.0 changed the name as "pci.0" to support MULTBUS a couple days > ago. > > If libvirt still parses the name as "pci" with QEMU_CAPS_PCI_MULTIBUS > disabled, > it will report the error "Bus 'pci' not found". > > I may need to add a PPC64 condition if X86 always enables MULTIBUS. Yeah, I see. But then again, I think we need a different patch after all:

diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c index 381b3ec..a14161d 100644 --- a/src/qemu/qemu_capabilities.c +++ b/src/qemu/qemu_capabilities.c @@ -2940,10 +2940,13 @@ virQEMUCapsInitArchQMPBasic(virQEMUCapsPtr qemuCaps, } /* - * Currently only x86_64 and i686 support PCI-multibus, - * -no-acpi and -no-kvm-pit-reinjection. + * Currently only x86_64, i686 and PPC64 support PCI-multibus. + * Moreover, the first two arches support -no-acpi and + * -no-kvm-pit-reinjection. */ - if (qemuCaps->arch == VIR_ARCH_X86_64 || + if (qemuCaps->arch == VIR_ARCH_PPC64) { + virQEMUCapsSet(qemuCaps, QEMU_CAPS_PCI_MULTIBUS); + } else if (qemuCaps->arch == VIR_ARCH_X86_64 || qemuCaps->arch == VIR_ARCH_I686) { virQEMUCapsSet(qemuCaps, QEMU_CAPS_PCI_MULTIBUS); virQEMUCapsSet(qemuCaps, QEMU_CAPS_NO_ACPI); Michal