[PATCH + RFC] Cascading option --with-kvm-trace to qemu configure script

[Lucas Meneghel Rodrigues <lmr@redhat.com>]

We've found a build issue on release tarballs: if we take a recent
release tarball, build it using the usual sequence

./configure
make
make install

The modules generated can't be loaded due to unresolved symbols related
to kvm trace. While fixing the problem, we noticed that is not possible
to pass the --with-kvm-trace option to the main qemu configure script.

This patch makes it possible to cascade --with-kvm-trace option from the
qemu toplevel configure script to the KVM kernel configure script. It is
our understanding that this cascading is desirable, however we are not
completely sure about it, hence we are asking for comments on this
change.

The actual fix for the issue we found will follow, however the patches
are independant.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>

--- configure	2009-05-19 13:29:02.000000000 -0300
+++ ../configure.backup	2009-05-26 21:16:53.702104650 -0300
@@ -198,6 +198,7 @@
 mixemu="no"
 bluez="yes"
 kvm="yes"
+kvm_trace="no"
 kvm_cap_pit="no"
 kvm_cap_device_assignment="no"
 kerneldir=""
@@ -521,6 +522,8 @@
   ;;
   --kerneldir=*) kerneldir="$optarg"
   ;;
+  --with-kvm-trace) kvm_trace="yes"
+  ;;
   --with-pkgversion=*) pkgversion=" ($optarg)"
   ;;
   --disable-cpu-emulation) cpu_emulation="no"
@@ -656,6 +659,7 @@
 echo "  --enable-io-thread       enable IO thread"
 echo "  --disable-blobs          disable installing provided firmware blobs"
 echo "  --kerneldir=PATH         look for kernel includes in PATH"
+echo "  --with-kvm-trace         enable building the KVM module with the kvm trace option"
 echo "  --disable-cpu-emulation  disables use of qemu cpu emulation code"
 echo ""
 echo "NOTE: The object files are built at the place where configure is launched"
@@ -1402,7 +1406,10 @@
     kvm_kmod="yes"
     kmod_args=""
     if test -n "$kerneldir"; then
-	kmod_args="--kerneldir=$kerneldir"
+        kmod_args="--kerneldir=$kerneldir"
+    fi
+    if test "$kvm_trace" = "yes"; then
+        kmod_args="$kmod_args --with-kvm-trace"
     fi
     # hope there are no spaces in kmod_args; can't use arrays because of
     # dash.
@@ -1470,6 +1477,7 @@
 echo "IO thread         $io_thread"
 echo "Install blobs     $blobs"
 echo "KVM support       $kvm"
+echo "KVM trace support $kvm_trace"
 echo "fdt support       $fdt"
 echo "preadv support    $preadv"
 





-- 
Lucas Meneghel Rodrigues
Software Engineer (QE)
Red Hat - Emerging Technologies