[libvirt] [PATCH] qemu_driver: Try KVM_CAP_MAX_VCPUS only if defined

[Michal Privoznik]

With our recent patch (1715c83b5f) we thrive to get the correct
number of maximal VCPUs. However, we are using a constant from
linux/kvm.h which may be not defined in every distro. Hence, we
should guard usage of the constant with ifdef preprocessor
directive.
---
 src/qemu/qemu_driver.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index de53a1b..c3a8f24 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -1122,9 +1122,11 @@ kvmGetMaxVCPUs(void) {
         return -1;
     }
 
+#ifdef KVM_CAP_MAX_VCPUS
     /* at first try KVM_CAP_MAX_VCPUS to determine the maximum count */
     if ((ret = ioctl(fd, KVM_CHECK_EXTENSION, KVM_CAP_MAX_VCPUS)) > 0)
         goto cleanup;
+#endif /* KVM_CAP_MAX_VCPUS */
 
     /* as a fallback get KVM_CAP_NR_VCPUS (the recommended maximum number of
      * vcpus). Note that on most machines this is set to 160. */
-- 
1.8.1.5