kvm tools: Repair running on non ioeventfd-capable platforms

Commit d3923126a24212f1e746a84a575dadbd9f259418 added a bunch of
nice error checking around ioevent__init() but the init may gracefully
fail if ioevents simply aren't supported (PPC64 KVM).

This commit adds a new return code for the init -- positive, but
identifiable as 'not success 0'.

Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

diff --git a/tools/kvm/ioeventfd.c b/tools/kvm/ioeventfd.c
index 9133101ebb02d8f12c06c6211522511b7727e59a..f2d5a302ff272c9ea334133e020233e517e7cd38 100644 (file)
--- a/tools/kvm/ioeventfd.c
+++ b/tools/kvm/ioeventfd.c
@@ -67,7 +67,7 @@ int ioeventfd__init(struct kvm *kvm)
 
        ioeventfd_avail = kvm__supports_extension(kvm, KVM_CAP_IOEVENTFD);
        if (!ioeventfd_avail)
-               return -ENOSYS;
+               return 1; /* Not fatal, but let caller determine no-go. */
 
        epoll_fd = epoll_create(IOEVENTFD_MAX_EVENTS);
        if (epoll_fd < 0)