other: 0.986 debug: 0.985 semantic: 0.980 graphic: 0.976 performance: 0.975 device: 0.975 PID: 0.974 boot: 0.965 socket: 0.955 files: 0.955 permissions: 0.954 vnc: 0.950 network: 0.949 KVM: 0.918 migration state save/load of sdcard device is broken I'm having different issues trying to have QEMU snapshots working using qemu-system-arm with vexpress-a15 board. In this opportunity, I'm trying the git master head version: # git rev-parse HEAD af352675efb7e92a1f5f6461a042a12015ab3d12 $ /usr/local/bin/qemu-system-arm -kernel kernel/vmlinuz-4.10.0-42-generic -initrd kernel/initrd.img-4.10.0-42-generic -M vexpress-a15 -m 2048 -append 'root=/dev/mmcblk0 rootwait console=tty0' -sd vexpress-4G.qcow2 -dtb device-tree/vexpress-v2p-ca15-tc1.dtb audio: Could not init `oss' audio driver Later on, when the machine finishes booting I savevm ss and quit. However, when I try to restore it, I have that Missing section footer error: $ /usr/local/bin/qemu-system-arm -kernel kernel/vmlinuz-4.10.0-42-generic -initrd kernel/initrd.img-4.10.0-42-generic -M vexpress-a15 -m 2048 -append 'root=/dev/mmcblk0 rootwait console=tty0' -sd vexpress-4G.qcow2 -dtb device-tree/vexpress-v2p-ca15-tc1.dtb -loadvm ss audio: Could not init `oss' audio driver qemu-system-arm: Missing section footer for sd-card qemu-system-arm: Error -22 while loading VM state OS: Ubuntu 16.04.3 LTS (xenial) $ gcc --version gcc (Ubuntu 5.4.0-6ubuntu1~16.04.5) 5.4.0 20160609 I've also tried a different ./configure line, explicitly enabling some of the features, i.e. smartcard, with the same results: ./configure '--disable-user' '--enable-system' '--enable-linux-user' '--enable-modules' '--enable-linux-aio' '--audio-drv-list=pa' '--enable-attr' '--enable-brlapi' '--enable-virtfs' '--enable-cap-ng' '--enable-curl' '--enable-fdt' '--enable-gnutls' '--disable-gtk' '--disable-vte' '--enable-libiscsi' '--enable-curses' '--enable-smartcard' '--enable-rbd' '--enable-vnc-sasl' '--enable-seccomp' '--enable-spice' '--enable-libusb' '--enable-usb-redir' '--enable-xfsctl' '--enable-vnc' '--enable-vnc-jpeg' '--enable-vnc-png' '--enable-kvm' '--enable-vhost-net' How have I built it? # git clone git://git.qemu.org/qemu.git # cd qemu # git submodule update --init --checkout # make clean && ./configure --target-list=arm-softmmu && make -j8 # sudo make install As a reference, and just in case these may be in some way related, I've just submitted another ticket for a different issue with snapshots using Ubuntu Qemu version (https://bugs.launchpad.net/qemu/+bug/1739371) Cheers, Gus From a quick look my guess would be the wpgrps_size in sd_vmstate is different on the source and destination for some reason - it's the only thing that seems to be variable. (It could also be whether the subsection is transmitted or not, but that's supposed to sort itself out automatically). So, it should be only related to SD? Which virtual device/storage backend do you recommend for snapshots? On 20 December 2017 at 18:44, Dr. David Alan Gilbert