解决 file /isolinux/vmlinuz0 not found

用centos7打了一个livecd，详细过程就不说了，在mbr机器上安装没有问题，但在efi设备上安装时会报告：
file /isolinux/vmlinuz0 not found
进grub2命令行调试：

>ls
后只能找到 efi 目录，找不到cdrom下的其他目录。
 

这种情况应该是root目录设置有问题，解压开cdrom中的efiboot.img,看 grub.cfg

set default="0"

function load_video {
  insmod efi_gop
  insmod efi_uga
  insmod video_bochs
  insmod video_cirrus
  insmod all_video
}

load_video
set gfxpayload=keep
insmod gzio
insmod part_gpt
insmod ext2

set timeout=30

menuentry 'Install or Upgrade MCOS-cServer-host-x86-4.4.0-201608150617' --class fedora --class gnu-linux --class gnu --class os {
        linuxefi /isolinux/vmlinuz0 crashkernel=256M root=live:CDLABEL=massclouds-node-iso rootfstype=auto ro liveimg rootflags=ro elevator=deadline install rhgb rd_NO_MULTIPATH rd.luks=0 rd.md=0 rd.dm=0 kvm-intel.nested=1
        initrdefi /isolinux/initrd0.img
}
menuentry 'Install or Upgrade with serial console MCOS-cServer-host-x86-4.4.0-201608150617' --class fedora --class gnu-linux --class gnu --class os {
        linuxefi /isolinux/vmlinuz0 crashkernel=256M root=live:CDLABEL=massclouds-node-iso rootfstype=auto ro liveimg rootflags=ro elevator=deadline install rhgb rd_NO_MULTIPATH rd.luks=0 rd.md=0 rd.dm=0  console=ttyS0,115200n8 kvm-intel.nested=1
        initrdefi /isolinux/initrd0.img
}
menuentry 'Reinstall MCOS-cServer-host-x86-4.4.0-201608150617' --class fedora --class gnu-linux --class gnu --class os {
        linuxefi /isolinux/vmlinuz0 crashkernel=256M root=live:CDLABEL=massclouds-node-iso rootfstype=auto ro liveimg rootflags=ro elevator=deadline install rhgb rd_NO_MULTIPATH rd.luks=0 rd.md=0 rd.dm=0  reinstall kvm-intel.nested=1
        initrdefi /isolinux/initrd0.img
}
menuentry 'Reinstall with serial console MCOS-cServer-host-x86-4.4.0-201608150617' --class fedora --class gnu-linux --class gnu --class os {
        linuxefi /isolinux/vmlinuz0 crashkernel=256M root=live:CDLABEL=massclouds-node-iso rootfstype=auto ro liveimg rootflags=ro elevator=deadline install rhgb rd_NO_MULTIPATH rd.luks=0 rd.md=0 rd.dm=0  reinstall console=ttyS0,115200n8 kvm-intel.nested=1
        initrdefi /isolinux/initrd0.img
}
menuentry 'Uninstall' --class fedora --class gnu-linux --class gnu --class os {
        linuxefi /isolinux/vmlinuz0 crashkernel=256M root=live:CDLABEL=massclouds-node-iso rootfstype=auto ro liveimg rootflags=ro elevator=deadline install rhgb rd_NO_MULTIPATH rd.luks=0 rd.md=0 rd.dm=0  uninstall kvm-intel.nested=1
        initrdefi /isolinux/initrd0.img
}

对比centos的efiboot.img中的grub.cfg

set default="1"

function load_video {
  insmod efi_gop
  insmod efi_uga
  insmod video_bochs
  insmod video_cirrus
  insmod all_video
}

load_video
set gfxpayload=keep
insmod gzio
insmod part_gpt
insmod ext2

set timeout=60
### END /etc/grub.d/00_header ###

search --no-floppy --set=root -l 'CentOS 7 x86_64'

### BEGIN /etc/grub.d/10_linux ###
menuentry 'Install CentOS Linux 7' --class fedora --class gnu-linux --class gnu --class os {
    linuxefi /images/pxeboot/vmlinuz inst.stage2=hd:LABEL=CentOS\x207\x20x86_64 quiet
    initrdefi /images/pxeboot/initrd.img
}
menuentry 'Test this media & install CentOS Linux 7' --class fedora --class gnu-linux --class gnu --class os {
    linuxefi /images/pxeboot/vmlinuz inst.stage2=hd:LABEL=CentOS\x207\x20x86_64 rd.live.check quiet
    initrdefi /images/pxeboot/initrd.img
}
submenu 'Troubleshooting -->' {
    menuentry 'Install CentOS Linux 7 in basic graphics mode' --class fedora --class gnu-linux --class gnu --class os {
        linuxefi /images/pxeboot/vmlinuz inst.stage2=hd:LABEL=CentOS\x207\x20x86_64 xdriver=vesa nomodeset quiet
        initrdefi /images/pxeboot/initrd.img
    }
    menuentry 'Rescue a CentOS Linux system' --class fedora --class gnu-linux --class gnu --class os {
        linuxefi /images/pxeboot/vmlinuz inst.stage2=hd:LABEL=CentOS\x207\x20x86_64 rescue quiet
        initrdefi /images/pxeboot/initrd.img
    }
}

缺少了一行：
search --no-floppy --set=root -l 'massclouds-node-iso'
将这一行添加到livecd中efiboot.img中的grub.cfg中打包测试。