Re: [libvirt PATCH v3 13/13] qemu: format sev-guest.kernel-hashes property
On Fri, Dec 10, 2021 at 16:47:13 +0000, Daniel P. Berrangé wrote:
Set the kernel-hashes property on the sev-guest object if
the config asked for it explicitly. While QEMU machine
types currently default to having this setting off, it
is not guaranteed to remain this way.
Signed-off-by: Daniel P. Berrangé <berrange(a)redhat.com>
---
src/qemu/qemu_command.c | 1 +
src/qemu/qemu_validate.c | 7 ++++
...unch-security-sev-direct.x86_64-6.2.0.args | 40 +++++++++++++++++++
.../launch-security-sev-direct.xml | 39 ++++++++++++++++++
tests/qemuxml2argvtest.c | 1 +
5 files changed, 88 insertions(+)
create mode 100644 tests/qemuxml2argvdata/launch-security-sev-direct.x86_64-6.2.0.args
create mode 100644 tests/qemuxml2argvdata/launch-security-sev-direct.xml
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 613f7a5d2a..dfbf4973f5 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -9894,6 +9894,7 @@ qemuBuildSEVCommandLine(virDomainObj *vm, virCommand *cmd,
"u:policy", sev->policy,
"S:dh-cert-file", dhpath,
"S:session-file", sessionpath,
+ "T:kernel-hashes", sev->kernel_hashes,
Since this is an '-object' ...
NULL) < 0)
return -1;
diff --git a/src/qemu/qemu_validate.c b/src/qemu/qemu_validate.c
index 29b01495ad..c0dc1f7b53 100644
--- a/src/qemu/qemu_validate.c
+++ b/src/qemu/qemu_validate.c
@@ -1200,6 +1200,13 @@ qemuValidateDomainDef(const virDomainDef *def,
"this QEMU binary"));
return -1;
}
+
+ if (def->sec->data.sev.kernel_hashes == VIR_TRISTATE_BOOL_YES
&&
+ !virQEMUCapsGet(qemuCaps, QEMU_CAPS_SEV_GUEST_KERNEL_HASHES)) {
... and this flag means that the 'sev-guest' actually has the
'kernel-hashes' property, the above check should be
if (def->sec->data.sev.kernel_hashes != VIR_TRISTATE_BOOL_ABSENT && ...
as an explicit disable will also cause a qemu error when the property is
not defined inside sev-guest.
Other option is to use 'B:kernel-hashes' above and extract the value of
sev->kernel_hashes into a temporary bool initialized to false via
virTristateBoolToBool which preserves the default. In such case it will
be always omitted when not enabled.
Reviewed-by: Peter Krempa <pkrempa(a)redhat.com>