From Dan Williams

This commit in -next (071b39575679 ACPICA: Tables: Back port
acpi_get_table_with_size() and early_acpi_os_unmap_memory() from Linux
kernel) causes a regression in my nfit/nvdimm test environment. The
nfit produced by QEMU no longer results in a nvdimm bus being created.

I have not root caused it, but I'm using the following command line
options to create an nfit in qemu-2.6.  Reverting the commit leads
compile failures.

qemu=$HOME/git/qemu/build/x86_64-softmmu/qemu-system-x86_64
mem=$HOME/mem
label_size=$((128*1024))
mem_size=$(((3*1024*1024*1024) + (64 * 1024 *1024)))
IMAGE=$HOME/ahci.img

kvm=(
        $qemu
        -enable-kvm
        -cpu kvm64
        -kernel $kernel
        -initrd $initrd
        -m 12G,slots=3,maxmem=40G

        -machine pc-i440fx-2.4,accel=kvm,usb=off,vmport=off,nvdimm
        -cpu SandyBridge
        -smp 2
        -netdev tap,id=hostnet0,ifname=tap0,script=no,downscript=no
        -device
virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:b7:a1:ad,bus=pci.0,addr=0x7
        -object
memory-backend-file,id=mem1,share,mem-path=${mem},size=$((label_size +
mem_size))
        -device nvdimm,memdev=mem1,id=nv1,label-size=${label_size}
        -device ahci,id=sata0,bus=pci.0,addr=0x8
        -drive file=$IMAGE,if=none,id=drive-sata0-0-0,format=raw
        -device ide-hd,bus=sata0.0,drive=drive-sata0-0-0,id=sata0-0-0
        -boot order=nc
        -no-reboot
        -watchdog i6300esb
        -rtc base=localtime
        -serial stdio
        -display none
        -monitor null
)