[libvirt PATCH 1/1] qemu: Use virQEMUCapsCacheLookupDefault instead of lookup by arch

Erik Skultety eskultet at redhat.com
Fri Jul 3 13:14:48 UTC 2020

Firstly, SEV is present only on AMD, so we can safely assume x86.
Secondly, the problem with looking up capabilities in the cache by arch
is that it's using virHashSearch with a callback to find the right
capabilities and get the binary name from it as well, but since the
cache is empty, it will return NULL and we won't get the corresponding
binary name out of the lookup either. Then, during the cache validation
we try to create a new cache entry for the emulator, but since we don't
have the binary name, nothing gets created.
Therefore, virQEMUCapsCacheLookupDefault is used to fix this issue,
because it doesn't rely on the capabilities cache to construct the
emulator binary name.


Signed-off-by: Erik Skultety <eskultet at redhat.com>
 src/qemu/qemu_driver.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index a5b38b3d24..cd8d7ffb56 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -22823,8 +22823,10 @@ qemuNodeGetSEVInfo(virConnectPtr conn,
     if (virNodeGetSevInfoEnsureACL(conn) < 0)
         return -1;
-    qemucaps = virQEMUCapsCacheLookupByArch(driver->qemuCapsCache,
-                                            virArchFromHost());
+    qemucaps = virQEMUCapsCacheLookupDefault(driver->qemuCapsCache,
+                                             NULL, NULL, NULL, NULL,
+                                             NULL, NULL, NULL);
     if (!qemucaps)
         return -1;

More information about the libvir-list mailing list