Re: [libvirt] [PATCH] qemu_capabilities: fix issue with discarding old capabilities

There was a bug that if libvirtd binary has been updated than the capability file wasn't reloaded therefore new capabilities introduced in libvirt cannot be used because the cached version was loaded. Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1135431

diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c index 81ada48..dae89aa 100644 --- a/src/qemu/qemu_capabilities.c +++ b/src/qemu/qemu_capabilities.c @@ -286,6 +286,7 @@ struct _virQEMUCaps { char *binary; time_t ctime; + time_t selfctime; virBitmapPtr flags; @@ -2689,7 +2690,7 @@ virQEMUCapsSaveCache(virQEMUCapsPtr qemuCaps, const char *filename) virBufferAsprintf(&buf, "<qemuctime>%llu</qemuctime>\n", (long long)qemuCaps->ctime); virBufferAsprintf(&buf, "<selfctime>%llu</selfctime>\n", - (long long)virGetSelfLastChanged()); + (long long)qemuCaps->selfctime); if (qemuCaps->usedQMP) virBufferAddLit(&buf, "<usedQMP/>\n"); @@ -2743,7 +2744,7 @@ virQEMUCapsSaveCache(virQEMUCapsPtr qemuCaps, const char *filename) VIR_DEBUG("Saved caps '%s' for '%s' with (%lld, %lld)", filename, qemuCaps->binary, (long long)qemuCaps->ctime, - (long long)virGetSelfLastChanged()); + (long long)qemuCaps->selfctime); ret = 0; cleanup: @@ -2871,12 +2872,12 @@ virQEMUCapsInitCached(virQEMUCapsPtr qemuCaps, const char *cacheDir) /* Discard if cache is older that QEMU binary */ if (qemuctime != qemuCaps->ctime || - selfctime < virGetSelfLastChanged()) { + selfctime < qemuCaps->selfctime) { VIR_DEBUG("Outdated cached capabilities '%s' for '%s' " "(%lld vs %lld, %lld vs %lld)", capsfile, qemuCaps->binary, (long long)qemuctime, (long long)qemuCaps->ctime, - (long long)selfctime, (long long)virGetSelfLastChanged()); + (long long)selfctime, (long long)qemuCaps->selfctime); ignore_value(unlink(capsfile)); virQEMUCapsReset(qemuCaps); ret = 0; @@ -3371,6 +3372,7 @@ virQEMUCapsPtr virQEMUCapsNewForBinary(const char *binary, goto error; } qemuCaps->ctime = sb.st_ctime; + qemuCaps->selfctime = virGetSelfLastChanged(); /* Make sure the binary we are about to try exec'ing exists. * Technically we could catch the exec() failure, but that's @@ -3420,7 +3422,8 @@ bool virQEMUCapsIsValid(virQEMUCapsPtr qemuCaps) if (stat(qemuCaps->binary, &sb) < 0) return false; - return sb.st_ctime == qemuCaps->ctime; + return sb.st_ctime == qemuCaps->ctime && + virGetSelfLastChanged() >= qemuCaps->selfctime; }