[libvirt] [PATCHv3 2/4] qemu: Add range checking for scheduler tunables when changed by API
The quota and period tunables for cpu scheduler accept only a certain
range of values. When changing the live configuration invalid values get
rejected. This check is not performed when changing persistent config.
This patch adds a separate range check, that improves error messages
when changing live config and adds the check for persistent config.
This check is done only when using the API. It is still possible to
specify invalid values in the XML.
---
src/qemu/qemu_driver.c | 27 +++++++++++++++++++++++++++
1 file changed, 27 insertions(+)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 4b8b751..8e8e00c 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -106,6 +106,11 @@
#define QEMU_NB_TOTAL_CPU_STAT_PARAM 3
#define QEMU_NB_PER_CPU_STAT_PARAM 2
+#define QEMU_SCHED_MIN_PERIOD 1000LL
+#define QEMU_SCHED_MAX_PERIOD 1000000LL
+#define QEMU_SCHED_MIN_QUOTA 1000LL
+#define QEMU_SCHED_MAX_QUOTA 18446744073709551LL
+
#if HAVE_LINUX_KVM_H
# include <linux/kvm.h>
#endif
@@ -7790,6 +7795,15 @@ cleanup:
return -1;
}
+#define SCHED_RANGE_CHECK(VAR, NAME, MIN, MAX) \
+ if (((VAR) > 0 && (VAR) < (MIN)) || (VAR) > (MAX)) {
\
+ virReportError(VIR_ERR_INVALID_ARG, \
+ _("value of '%s' is out of range [%lld, %lld]"),
\
+ NAME, MIN, MAX); \
+ rc = -1; \
+ goto cleanup; \
+ }
+
static int
qemuSetSchedulerParametersFlags(virDomainPtr dom,
virTypedParameterPtr params,
@@ -7876,6 +7890,9 @@ qemuSetSchedulerParametersFlags(virDomainPtr dom,
vmdef->cputune.shares = value_ul;
} else if (STREQ(param->field, VIR_DOMAIN_SCHEDULER_VCPU_PERIOD)) {
+ SCHED_RANGE_CHECK(value_ul, VIR_DOMAIN_SCHEDULER_VCPU_PERIOD,
+ QEMU_SCHED_MIN_PERIOD, QEMU_SCHED_MAX_PERIOD);
+
if (flags & VIR_DOMAIN_AFFECT_LIVE && value_ul) {
if ((rc = qemuSetVcpusBWLive(vm, group, value_ul, 0)))
goto cleanup;
@@ -7887,6 +7904,9 @@ qemuSetSchedulerParametersFlags(virDomainPtr dom,
vmdef->cputune.period = params[i].value.ul;
} else if (STREQ(param->field, VIR_DOMAIN_SCHEDULER_VCPU_QUOTA)) {
+ SCHED_RANGE_CHECK(value_l, VIR_DOMAIN_SCHEDULER_VCPU_QUOTA,
+ QEMU_SCHED_MIN_QUOTA, QEMU_SCHED_MAX_QUOTA);
+
if (flags & VIR_DOMAIN_AFFECT_LIVE && value_l) {
if ((rc = qemuSetVcpusBWLive(vm, group, 0, value_l)))
goto cleanup;
@@ -7898,6 +7918,9 @@ qemuSetSchedulerParametersFlags(virDomainPtr dom,
vmdef->cputune.quota = value_l;
} else if (STREQ(param->field, VIR_DOMAIN_SCHEDULER_EMULATOR_PERIOD)) {
+ SCHED_RANGE_CHECK(value_ul, VIR_DOMAIN_SCHEDULER_EMULATOR_PERIOD,
+ QEMU_SCHED_MIN_PERIOD, QEMU_SCHED_MAX_PERIOD);
+
if (flags & VIR_DOMAIN_AFFECT_LIVE && value_ul) {
if ((rc = qemuSetEmulatorBandwidthLive(vm, group, value_ul, 0)))
goto cleanup;
@@ -7909,6 +7932,9 @@ qemuSetSchedulerParametersFlags(virDomainPtr dom,
vmdef->cputune.emulator_period = value_ul;
} else if (STREQ(param->field, VIR_DOMAIN_SCHEDULER_EMULATOR_QUOTA)) {
+ SCHED_RANGE_CHECK(value_l, VIR_DOMAIN_SCHEDULER_EMULATOR_QUOTA,
+ QEMU_SCHED_MIN_QUOTA, QEMU_SCHED_MAX_QUOTA);
+
if (flags & VIR_DOMAIN_AFFECT_LIVE && value_l) {
if ((rc = qemuSetEmulatorBandwidthLive(vm, group, 0, value_l)))
goto cleanup;
@@ -7944,6 +7970,7 @@ cleanup:
qemuDriverUnlock(driver);
return ret;
}
+#undef SCHED_RANGE_CHECK
static int
qemuSetSchedulerParameters(virDomainPtr dom,
--
1.7.12