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@xxxxxxxx> --- 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
