Commit 9850c604 authored by Alexander Graf's avatar Alexander Graf Committed by Juan Quintela
Browse files

migration: Allow to suppress vmdesc submission 



We now always send a JSON blob describing the migration file format as part
of the migration stream. However, some tools built around QEMU have proven
to stumble over this.

This patch gives the user the chance to disable said self-describing part of
the migration stream. To disable vmdesc submission, just add

  -machine suppress-vmdesc=on

to your QEMU command line.

Signed-off-by: default avatarAlexander Graf <agraf@suse.de>
Signed-off-by: default avatarJuan Quintela <quintela@redhat.com>
parent 1925cebc

hw/core/machine.c

+20 −0
Original line number Diff line number Diff line
@@ -254,6 +254,20 @@ static void machine_set_iommu(Object *obj, bool value, Error **errp) 
    ms->iommu = value;

}



static void machine_set_suppress_vmdesc(Object *obj, bool value, Error **errp)

{

    MachineState *ms = MACHINE(obj);



    ms->suppress_vmdesc = value;

}



static bool machine_get_suppress_vmdesc(Object *obj, Error **errp)

{

    MachineState *ms = MACHINE(obj);



    return ms->suppress_vmdesc;

}



static int error_on_sysbus_device(SysBusDevice *sbdev, void *opaque)

{

    error_report("Option '-device %s' cannot be handled by this machine",
@@ -377,6 +391,12 @@ static void machine_initfn(Object *obj) 
    object_property_set_description(obj, "iommu",

                                    "Set on/off to enable/disable Intel IOMMU (VT-d)",

                                    NULL);

    object_property_add_bool(obj, "suppress-vmdesc",

                             machine_get_suppress_vmdesc,

                             machine_set_suppress_vmdesc, NULL);

    object_property_set_description(obj, "suppress-vmdesc",

                                    "Set on to disable self-describing migration",

                                    NULL);



    /* Register notifier when init is done for sysbus sanity checks */

    ms->sysbus_notifier.notify = machine_init_notify;

include/hw/boards.h

+1 −0
Original line number Diff line number Diff line
@@ -143,6 +143,7 @@ struct MachineState { 
    bool usb;

    char *firmware;

    bool iommu;

    bool suppress_vmdesc;



    ram_addr_t ram_size;

    ram_addr_t maxram_size;

qemu-options.hx

+2 −1
Original line number Diff line number Diff line
@@ -39,7 +39,8 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ 
    "                mem-merge=on|off controls memory merge support (default: on)\n"

    "                iommu=on|off controls emulated Intel IOMMU (VT-d) support (default=off)\n"

    "                aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n"

    "                dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n",

    "                dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n"

    "                suppress-vmdesc=on|off disables self-describing migration (default=off)\n",

    QEMU_ARCH_ALL)

STEXI

@item -machine [type=]@var{name}[,prop=@var{value}[,...]]

savevm.c

+11 −3
Original line number Diff line number Diff line
@@ -710,6 +710,12 @@ int qemu_savevm_state_iterate(QEMUFile *f) 
    return ret;

}



static bool should_send_vmdesc(void)

{

    MachineState *machine = MACHINE(qdev_get_machine());

    return !machine->suppress_vmdesc;

}



void qemu_savevm_state_complete(QEMUFile *f)

{

    QJSON *vmdesc;
@@ -782,9 +788,11 @@ void qemu_savevm_state_complete(QEMUFile *f) 
    qjson_finish(vmdesc);

    vmdesc_len = strlen(qjson_get_str(vmdesc));



    if (should_send_vmdesc()) {

        qemu_put_byte(f, QEMU_VM_VMDESCRIPTION);

        qemu_put_be32(f, vmdesc_len);

        qemu_put_buffer(f, (uint8_t *)qjson_get_str(vmdesc), vmdesc_len);

    }

    object_unref(OBJECT(vmdesc));



    qemu_fflush(f);