qemux86: Support for KVM, paravirt and virtio added

KVM, paravirtualization and virtio drivers are now activated
in runqemu using the kvm option flag for qemux86.
Host CPU features are also exported to guest OS (Yocto Linux).
Usage example: runqemu qemux86 core-image-x11 kvm

Implements [YOCTO #2550].

Signed-off-by: Cristian Iorga <cristian.iorga@intel.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>

diff --git a/meta/recipes-kernel/linux/linux-yocto_3.4.bb b/meta/recipes-kernel/linux/linux-yocto_3.4.bb
index 7c082e75ad70bbba137acfe2f23978abb560edf8..32ae02b5128dba5294a3ee14f77d582958d097d0 100644 (file)
--- a/meta/recipes-kernel/linux/linux-yocto_3.4.bb
+++ b/meta/recipes-kernel/linux/linux-yocto_3.4.bb
@@ -27,4 +27,5 @@ KERNEL_REVISION_CHECKING=""
 KERNEL_FEATURES_append = " features/netfilter"
 KERNEL_FEATURES_append_qemux86=" cfg/sound"
 KERNEL_FEATURES_append_qemux86-64=" cfg/sound"
+KERNEL_FEATURES_append_qemux86=" cfg/paravirt_kvm"
 KERNEL_FEATURES_append = " ${@bb.utils.contains("TUNE_FEATURES", "mx32", " cfg/x32", "" ,d)}"

diff --git a/scripts/runqemu b/scripts/runqemu
index a9f513c7a91b112cb12577ca7ddcafed33b64730..e6e43f20c8a0460d0c38ff75fc3da20a6b37089f 100755 (executable)
--- a/scripts/runqemu
+++ b/scripts/runqemu
@@ -208,6 +208,7 @@ if [ -z "$MACHINE" ]; then
 fi
 
 YOCTO_KVM_WIKI="https://wiki.yoctoproject.org/wiki/How_to_enable_KVM_for_Poky_qemu"
+YOCTO_PARAVIRT_KVM_WIKI="https://wiki.yoctoproject.org/wiki/Running_an_x86_Yocto_Linux_image_under_QEMU_KVM"
 # Detect KVM configuration
 if [ "x$KVM_ENABLED" = "xyes" ]; then
     if [ -z "$KVM_CAPABLE" ]; then
@@ -226,14 +227,27 @@ if [ "x$KVM_ENABLED" = "xyes" ]; then
         echo "$YOCTO_KVM_WIKI";
         exit 1;
     fi
+    if [ ! -e /dev/vhost-net ]; then
+        echo "Missing virtio net device. Have you inserted vhost-net module?"
+        echo "For further help see"
+        echo "$YOCTO_PARAVIRT_KVM_WIKI";
+        exit 1;
+    fi
     if 9<>/dev/kvm ; then
-        SCRIPT_QEMU_OPT="$SCRIPT_QEMU_OPT -enable-kvm"
+        SCRIPT_QEMU_OPT="$SCRIPT_QEMU_OPT -enable-kvm -cpu host"
+        KVM_ACTIVE="yes"
     else
         echo "You have no rights on /dev/kvm."
         echo "Please change the ownership of this file as described at"
         echo "$YOCTO_KVM_WIKI";
         exit 1;
     fi
+    if [ ! -w /dev/vhost-net -a -r /dev/vhost-net ]; then
+        echo "You have no rights on /dev/vhost-net."
+        echo "Please change the ownership of this file as described at"
+        echo "$YOCTO_PARAVIRT_KVM_WIKI";
+        exit 1;
+    fi
 fi
 
 machine2=`echo $MACHINE | tr 'a-z' 'A-Z' | sed 's/-/_/'`

diff --git a/scripts/runqemu-internal b/scripts/runqemu-internal
index a9b1c44de49825eba670b9e59883c8dc0f21b275..f2c8d8309f4aa27ad1538a2115fdad37d62405e6 100755 (executable)
--- a/scripts/runqemu-internal
+++ b/scripts/runqemu-internal
@@ -221,7 +221,15 @@ n2=$(($n1 + 1))
 
 KERNEL_NETWORK_CMD="ip=192.168.7.$n2::192.168.7.$n1:255.255.255.0"
 QEMU_TAP_CMD="-net tap,vlan=0,ifname=$TAP,script=no,downscript=no"
-QEMU_NETWORK_CMD="-net nic,vlan=0 $QEMU_TAP_CMD"
+if [ "$KVM_ACTIVE" = "yes" ]; then
+    QEMU_NETWORK_CMD="-net nic,model=virtio $QEMU_TAP_CMD,vhost=on"
+    DROOT="/dev/vda"
+    ROOTFS_OPTIONS="-drive file=$ROOTFS,if=virtio"
+else
+    QEMU_NETWORK_CMD="-net nic,vlan=0 $QEMU_TAP_CMD"
+    DROOT="/dev/hda"
+    ROOTFS_OPTIONS="-hda $ROOTFS"
+fi
 KERNCMDLINE="mem=$QEMU_MEMORY"
 QEMU_UI_OPTIONS="-show-cursor -usb -usbdevice wacom-tablet"
 
@@ -321,8 +329,8 @@ if [ "$MACHINE" = "qemux86" ]; then
     QEMU=qemu-system-i386
     QEMU_UI_OPTIONS="$QEMU_UI_OPTIONS -vga vmware"
     if [ "$FSTYPE" = "ext2" -o "$FSTYPE" = "ext3" -o "$FSTYPE" = "btrfs" ]; then
-        KERNCMDLINE="vga=0 root=/dev/hda rw mem=$QEMU_MEMORY $KERNEL_NETWORK_CMD"
-        QEMUOPTIONS="$QEMU_NETWORK_CMD -hda $ROOTFS $QEMU_UI_OPTIONS"
+        KERNCMDLINE="vga=0 root=$DROOT rw mem=$QEMU_MEMORY $KERNEL_NETWORK_CMD"
+        QEMUOPTIONS="$QEMU_NETWORK_CMD $ROOTFS_OPTIONS $QEMU_UI_OPTIONS"
     fi
     if [ "$FSTYPE" = "nfs" ]; then
         if [ "$NFS_SERVER" = "192.168.7.1" -a ! -d "$NFS_DIR" ]; then