[Libguestfs] [PATCH] launch: direct: Only issue Debian /dev/kvm group warning if /dev/kvm wasn't openable (RHBZ#1130189).

[Richard W.M. Jones]

This warning was meant for the case where /dev/kvm is inaccessible and
the user must add themselves to a special group.

However we didn't take into account whether /dev/kvm was openable in
this test.  If it's openable, no point issuing the warning.

Move the is_openable ("/dev/kvm") test earlier, and don't issue the
warning if that was successful.
---
 src/launch-direct.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/src/launch-direct.c b/src/launch-direct.c
index 3bae254..3a8f2b2 100644
--- a/src/launch-direct.c
+++ b/src/launch-direct.c
@@ -289,11 +289,19 @@ launch_direct (guestfs_h *g, void *datav, const char *arg)
     return -1;
   }
 
+  /* Try to guess if KVM is available.  We are just checking that
+   * /dev/kvm is openable.  That's not reliable, since /dev/kvm
+   * might be openable by qemu but not by us (think: SELinux) in
+   * which case the user would not get hardware virtualization,
+   * although at least shouldn't fail.
+   */
+  has_kvm = is_openable (g, "/dev/kvm", O_RDWR|O_CLOEXEC);
+
   force_tcg = guestfs___get_backend_setting_bool (g, "force_tcg");
   if (force_tcg == -1)
     return -1;
 
-  if (!force_tcg)
+  if (!has_kvm && !force_tcg)
     debian_kvm_warning (g);
 
   guestfs___launch_send_progress (g, 0);
@@ -411,14 +419,6 @@ launch_direct (guestfs_h *g, void *datav, const char *arg)
     warning (g, "qemu debugging is enabled, connect gdb to tcp::1234 to begin");
   }
 
-  /* Try to guess if KVM is available.  We are just checking that
-   * /dev/kvm is openable.  That's not reliable, since /dev/kvm
-   * might be openable by qemu but not by us (think: SELinux) in
-   * which case the user would not get hardware virtualization,
-   * although at least shouldn't fail.
-   */
-  has_kvm = is_openable (g, "/dev/kvm", O_RDWR|O_CLOEXEC);
-
   cpu_model = guestfs___get_cpu_model (has_kvm && !force_tcg);
   if (cpu_model) {
     ADD_CMDLINE ("-cpu");
-- 
1.9.3