[libvirt] [PATCH] lxc: fix 2 issue around cpuset

[Luyao Huang]

There are two bugs in this function:

1. cannot start a vm with cpuset but without numatune settings

 # virsh -c lxc:/// start helloworld
 error: Failed to start domain helloworld
 error: internal error: guest failed to start: Invalid value '1-3' for 'cpuset.mems': Invalid argument

we don't free &mask after use it for virCgroupSetCpusetCpus() and
then virDomainNumatuneMaybeFormatNodeset() do not get a new &mask,
then we use it in virCgroupSetCpusetMems().

2. when start a lxc with numatune memory mode not strict

 # virsh -c lxc:/// start helloworld
 error: Failed to start domain helloworld
 error: internal error: guest failed to start: Unknown failure in libvirt_lxc startup

We shouldn't set anything in cpuset.mems for these mode.

Signed-off-by: Luyao Huang <lhuang at redhat.com>
---
 src/lxc/lxc_cgroup.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/lxc/lxc_cgroup.c b/src/lxc/lxc_cgroup.c
index c1813e2..5e959a2 100644
--- a/src/lxc/lxc_cgroup.c
+++ b/src/lxc/lxc_cgroup.c
@@ -77,11 +77,15 @@ static int virLXCCgroupSetupCpusetTune(virDomainDefPtr def,
 
         if (virCgroupSetCpusetCpus(cgroup, mask) < 0)
             goto cleanup;
+        /* free mask to make sure we won't use it in a wrong way later */
+        VIR_FREE(mask);
     }
 
     if (virDomainNumatuneGetMode(def->numa, -1) !=
-        VIR_DOMAIN_NUMATUNE_MEM_STRICT)
+        VIR_DOMAIN_NUMATUNE_MEM_STRICT) {
+        ret = 0;
         goto cleanup;
+    }
 
     if (virDomainNumatuneMaybeFormatNodeset(def->numa, nodemask,
                                             &mask, -1) < 0)
-- 
1.8.3.1