On Wed, Nov 29, 2017 at 03:58:57PM +0100, Ján Tomko wrote:
In status XML, we do not store the QEMU version information, we only
format all the capabilities. We dropped QEMU_CAPS_PCI_MULTIBUS
in commit 5b783379 which was released in libvirt 3.2.0.
Therefore the only way of telling if the already running domain
at the time of daemon restart has been started with a QEMU that does
use 'pci.0' or not on PPC is to look at the pci-root controller's
alias. This is not an option if the domain has a user-specified alias
for the pci-root.
Instead of reintroducing the capability, assume 'pci.0' when we have
no version information. That way the only left broken use case would
be the combination of user aliases and very old QEMU.
https://bugzilla.redhat.com/show_bug.cgi?id=1518148
---
src/qemu/qemu_capabilities.c | 16 ++++++++--------
src/qemu/qemu_capspriv.h | 4 ----
tests/qemuxml2argvtest.c | 5 -----
3 files changed, 8 insertions(+), 17 deletions(-)
diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
index c9d0a66d8..7b52d1a71 100644
--- a/src/qemu/qemu_capabilities.c
+++ b/src/qemu/qemu_capabilities.c
@@ -2436,6 +2436,14 @@ bool virQEMUCapsHasPCIMultiBus(virQEMUCapsPtr qemuCaps,
* ppce500: 1.6.0
*/
+ /* We do not store the qemu version in domain status XML.
+ * Hope the user is using a QEMU new enough to use 'pci.0',
+ * otherwise the results of this function will be wrong
+ * for domains already running at the time of daemon
+ * restart */
+ if (qemuCaps->version == 0)
+ return true;
+
I don't like this that we will hope that QEMU is new enough, but I
cannot think of a better way how to check it and this definitely
improves current code.
For the whole series:
Reviewed-by: Pavel Hrdina <phrdina(a)redhat.com>