[libvirt] [PATCH] qemu: Deny hugepages for non-existent NUMA nodes

[Michal Privoznik]

https://bugzilla.redhat.com/show_bug.cgi?id=1534418

Just like ec982f6d929f3c23 denies hugepages for non-existent
guest NUMA nodes in case there are some nodes configured.
Unfortunately, when there are none, qemuBuildNumaArgStr() is not
called and thus we have to have check in qemuBuildMemPathStr()
too.

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/qemu/qemu_command.c                     | 10 +++++++
 tests/qemuxml2argvdata/hugepages-pages8.xml | 41 +++++++++++++++++++++++++++++
 tests/qemuxml2argvtest.c                    |  3 +++
 3 files changed, 54 insertions(+)
 create mode 100644 tests/qemuxml2argvdata/hugepages-pages8.xml

diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index f3724a766b..af0af33bd1 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -7276,6 +7276,16 @@ qemuBuildMemPathStr(virQEMUDriverConfigPtr cfg,
     if (!def->mem.nhugepages)
         return 0;
 
+    if (def->mem.hugepages[0].nodemask) {
+        ssize_t next_bit = virBitmapNextSetBit(def->mem.hugepages[0].nodemask, -1);
+        if (next_bit >= 0) {
+            virReportError(VIR_ERR_XML_DETAIL,
+                           _("hugepages: node %zd not found"),
+                           next_bit);
+            return -1;
+        }
+    }
+
     /* There is one special case: if user specified "huge"
      * pages of regular system pages size.
      * And there is nothing to do in this case.
diff --git a/tests/qemuxml2argvdata/hugepages-pages8.xml b/tests/qemuxml2argvdata/hugepages-pages8.xml
new file mode 100644
index 0000000000..4cf4c1a8ad
--- /dev/null
+++ b/tests/qemuxml2argvdata/hugepages-pages8.xml
@@ -0,0 +1,41 @@
+<domain type='qemu'>
+  <name>SomeDummyHugepagesGuest</name>
+  <uuid>ef1bdff4-27f3-4e85-a807-5fb4d58463cc</uuid>
+  <memory unit='KiB'>1048576</memory>
+  <currentMemory unit='KiB'>1048576</currentMemory>
+  <memoryBacking>
+    <hugepages>
+      <page size='2048' unit='KiB' nodeset='1'/>
+    </hugepages>
+  </memoryBacking>
+  <vcpu placement='static'>2</vcpu>
+  <os>
+    <type arch='i686' machine='pc'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu-system-i686</emulator>
+    <disk type='block' device='disk'>
+      <driver name='qemu' type='raw'/>
+      <source dev='/dev/HostVG/QEMUGuest1'/>
+      <target dev='hda' bus='ide'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
+    </disk>
+    <controller type='usb' index='0'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
+    </controller>
+    <controller type='ide' index='0'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
+    </controller>
+    <controller type='pci' index='0' model='pci-root'/>
+    <input type='mouse' bus='ps2'/>
+    <input type='keyboard' bus='ps2'/>
+    <memballoon model='virtio'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
+    </memballoon>
+  </devices>
+</domain>
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index 78454acb1a..19801953e5 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -937,6 +937,9 @@ mymain(void)
     DO_TEST("hugepages-pages7",
             QEMU_CAPS_DEVICE_PC_DIMM, QEMU_CAPS_OBJECT_MEMORY_FILE,
             QEMU_CAPS_OBJECT_MEMORY_FILE_DISCARD);
+    DO_TEST_FAILURE("hugepages-pages8",
+                    QEMU_CAPS_DEVICE_PC_DIMM, QEMU_CAPS_OBJECT_MEMORY_FILE,
+                    QEMU_CAPS_OBJECT_MEMORY_FILE_DISCARD);
     DO_TEST("hugepages-memaccess", QEMU_CAPS_OBJECT_MEMORY_FILE,
             QEMU_CAPS_OBJECT_MEMORY_RAM, QEMU_CAPS_DEVICE_PC_DIMM,
             QEMU_CAPS_NUMA);
-- 
2.16.1