vircgroup: fix cpu quota maximum limit

Kernel commit <d505b8af58912ae1e1a211fabc9995b19bd40828> added proper
check for cpu quota maximum limit to prevent internal overflow.

Even though this change is not present in all kernels it makes sense
to enforce the same limit in libvirt.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1750315

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>

diff --git a/src/util/vircgroup.h b/src/util/vircgroup.h
index 2a9b3419854a493addbf6c78c78692241a57d9c1..ec0902e3017d2d21d47c179ba99d19a4b3ad5133 100644 (file)
--- a/src/util/vircgroup.h
+++ b/src/util/vircgroup.h
@@ -233,7 +233,9 @@ int virCgroupSetupCpuShares(virCgroupPtr cgroup, unsigned long long shares,
 #define VIR_CGROUP_CPU_PERIOD_MIN 1000LL
 #define VIR_CGROUP_CPU_PERIOD_MAX 1000000LL
 #define VIR_CGROUP_CPU_QUOTA_MIN 1000LL
-#define VIR_CGROUP_CPU_QUOTA_MAX 18446744073709551LL
+/* Based on kernel code ((1ULL << MAX_BW_BITS) - 1) where MAX_BW_BITS is
+ * (64 - BW_SHIFT) and BW_SHIFT is 20 */
+#define VIR_CGROUP_CPU_QUOTA_MAX 17592186044415LL
 
 int virCgroupSetCpuCfsPeriod(virCgroupPtr group, unsigned long long cfs_period);
 int virCgroupGetCpuCfsPeriod(virCgroupPtr group, unsigned long long *cfs_period);