6:03 p.m.
Add a configuration option for specifying location of the qemu modules
directory, defaulting to /usr/lib64/qemu. Then use this location to
check for changes in the directory, indicating that a qemu module has
changed and capabilities need to be reprobed.
Signed-off-by: Jim Fehlig <jfehlig(a)suse.com>
---
This is a mildly tested impl of the idea discussed here (and elsewhere
in the thread)
https://www.redhat.com/archives/libvir-list/2020-August/msg00684.html
I've checked that both system and session caches are updated when a
qemu modules package is updated. I'll do some more testing but wanted
to send the patch for early comments. Testing in other environments
would be much appreciated. Thanks!
meson.build | 6 ++++++
meson_options.txt | 1 +
src/qemu/qemu_capabilities.c | 35 +++++++++++++++++++++++++++++++++++
3 files changed, 42 insertions(+)
diff --git a/meson.build b/meson.build
index a72d0c0e85..16928482aa 100644
--- a/meson.build
+++ b/meson.build
@@ -1745,6 +1745,12 @@ if not get_option('driver_qemu').disabled()
if use_qemu
conf.set('WITH_QEMU', 1)
+ qemu_moddir = get_option('qemu_moddir')
+ if qemu_moddir == ''
+ qemu_moddir = '/usr/lib64/qemu'
+ endif
+ conf.set_quoted('QEMU_MODDIR', qemu_moddir)
+
if host_machine.system() in ['freebsd', 'darwin']
default_qemu_user = 'root'
default_qemu_group = 'wheel'
diff --git a/meson_options.txt b/meson_options.txt
index c538d323c1..cedbd79491 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -59,6 +59,7 @@ option('driver_openvz', type: 'feature', value:
'auto', description: 'OpenVZ dri
option('driver_qemu', type: 'feature', value: 'auto',
description: 'QEMU/KVM driver')
option('qemu_user', type: 'string', value: '', description:
'username to run QEMU system instance as')
option('qemu_group', type: 'string', value: '', description:
'groupname to run QEMU system instance as')
+option('qemu_moddir', type: 'string', value: '', description:
'set the directory where QEMU modules are located')
option('driver_remote', type: 'feature', value: 'enabled',
description: 'remote driver')
option('remote_default_mode', type: 'combo', choices: ['legacy',
'direct'], value: 'legacy', description: 'remote driver default
mode')
option('driver_secrets', type: 'feature', value: 'auto',
description: 'local secrets management driver')
diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
index ff6ba8c9e9..a00853c753 100644
--- a/src/qemu/qemu_capabilities.c
+++ b/src/qemu/qemu_capabilities.c
@@ -677,6 +677,7 @@ struct _virQEMUCaps {
char *binary;
time_t ctime;
time_t libvirtCtime;
+ time_t modDirMtime;
bool invalidation;
virBitmapPtr flags;
@@ -4194,6 +4195,7 @@ virQEMUCapsParseSEVInfo(virQEMUCapsPtr qemuCaps, xmlXPathContextPtr
ctxt)
* <qemuCaps>
* <emulator>/some/path</emulator>
* <qemuctime>234235253</qemuctime>
+ * <qemumoddirmtime>234235253</qemumoddirmtime>
* <selfctime>234235253</selfctime>
* <selfvers>1002016</selfvers>
* <flag name='foo'/>
@@ -4283,6 +4285,9 @@ virQEMUCapsLoadCache(virArch hostArch,
}
qemuCaps->ctime = (time_t)l;
+ if (virXPathLongLong("string(./qemumoddirmtime)", ctxt, &l) == 0)
+ qemuCaps->modDirMtime = (time_t)l;
+
if ((n = virXPathNodeSet("./flag", ctxt, &nodes)) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("failed to parse qemu capabilities flags"));
@@ -4615,6 +4620,10 @@ virQEMUCapsFormatCache(virQEMUCapsPtr qemuCaps)
qemuCaps->binary);
virBufferAsprintf(&buf, "<qemuctime>%llu</qemuctime>\n",
(long long)qemuCaps->ctime);
+ if (qemuCaps->modDirMtime > 0) {
+ virBufferAsprintf(&buf,
"<qemumoddirmtime>%llu</qemumoddirmtime>\n",
+ (long long)qemuCaps->modDirMtime);
+ }
virBufferAsprintf(&buf, "<selfctime>%llu</selfctime>\n",
(long long)qemuCaps->libvirtCtime);
virBufferAsprintf(&buf, "<selfvers>%lu</selfvers>\n",
@@ -4881,6 +4890,23 @@ virQEMUCapsIsValid(void *data,
if (!qemuCaps->binary)
return true;
+ if (virFileExists(QEMU_MODDIR)) {
+ if (stat(QEMU_MODDIR, &sb) < 0) {
+ VIR_DEBUG("Failed to stat QEMU module directory '%s': %s",
+ QEMU_MODDIR,
+ g_strerror(errno));
+ return false;
+ }
+
+ if (sb.st_mtime != qemuCaps->modDirMtime) {
+ VIR_DEBUG("Outdated capabilities for '%s': QEMU modules "
+ "directory '%s' changed (%lld vs %lld)",
+ qemuCaps->binary, QEMU_MODDIR,
+ (long long)sb.st_mtime, (long long)qemuCaps->modDirMtime);
+ return false;
+ }
+ }
+
if (qemuCaps->libvirtCtime != virGetSelfLastChanged() ||
qemuCaps->libvirtVersion != LIBVIR_VERSION_NUMBER) {
VIR_DEBUG("Outdated capabilities for '%s': libvirt changed "
@@ -5463,6 +5489,15 @@ virQEMUCapsNewForBinaryInternal(virArch hostArch,
goto error;
}
+ if (virFileExists(QEMU_MODDIR)) {
+ if (stat(QEMU_MODDIR, &sb) < 0) {
+ virReportSystemError(errno, _("Cannot check QEMU module directory
%s"),
+ QEMU_MODDIR);
+ goto error;
+ }
+ qemuCaps->modDirMtime = sb.st_mtime;
+ }
+
if (virQEMUCapsInitQMP(qemuCaps, libDir, runUid, runGid) < 0)
goto error;
--
2.28.0