Comment 21 for bug 1635339

Hi

On Mon, Apr 10, 2017 at 1:31 PM Gerd Hoffmann <email address hidden> wrote:

> Cc: <email address hidden>
> Signed-off-by: Gerd Hoffmann <email address hidden>
>

Reviewed-by: Marc-André Lureau <email address hidden>

> ---
> hw/display/qxl.h | 1 +
> hw/display/qxl.c | 31 +++++++++++++++++++++++++++++++
> 2 files changed, 32 insertions(+)
>
> diff --git a/hw/display/qxl.h b/hw/display/qxl.h
> index d2d49dd..77e5a36 100644
> --- a/hw/display/qxl.h
> +++ b/hw/display/qxl.h
> @@ -40,6 +40,7 @@ typedef struct PCIQXLDevice {
> uint32_t cmdlog;
>
> uint32_t guest_bug;
> + Error *migration_blocker;
>
> enum qxl_mode mode;
> uint32_t cmdflags;
> diff --git a/hw/display/qxl.c b/hw/display/qxl.c
> index c31b293..9feae78 100644
> --- a/hw/display/qxl.c
> +++ b/hw/display/qxl.c
> @@ -26,6 +26,7 @@
> #include "qemu/queue.h"
> #include "qemu/atomic.h"
> #include "sysemu/sysemu.h"
> +#include "migration/migration.h"
> #include "trace.h"
>
> #include "qxl.h"
> @@ -639,6 +640,30 @@ static int interface_get_command(QXLInstance *sin,
> struct QXLCommandExt *ext)
> qxl->guest_primary.commands++;
> qxl_track_command(qxl, ext);
> qxl_log_command(qxl, "cmd", ext);
> + {
> + /*
> + * Windows 8 drivers place qxl commands in the vram
> + * (instead of the ram) bar. We can't live migrate such a
> + * guest, so add a migration blocker in case we detect
> + * this, to avoid triggering the assert in pre_save().
> + *
> + *
> https://cgit.freedesktop.org/spice/win32/qxl-wddm-dod/commit/?id=f6e099db39e7d0787f294d5fd0dce328b5210faa
> + */
> + void *msg = qxl_phys2virt(qxl, ext->cmd.data, ext->group_id);
> + if (msg != NULL && (
> + msg < (void *)qxl->vga.vram_ptr ||
> + msg > ((void *)qxl->vga.vram_ptr +
> qxl->vga.vram_size))) {
> + if (!qxl->migration_blocker) {
> + Error *local_err = NULL;
> + error_setg(&qxl->migration_blocker,
> + "qxl: guest bug: command not in ram bar");
> + migrate_add_blocker(qxl->migration_blocker,
> &local_err);
> + if (local_err) {
> + error_report_err(local_err);
> + }
> + }
> + }
> + }
> trace_qxl_ring_command_get(qxl->id,
> qxl_mode_to_string(qxl->mode));
> return true;
> default:
> @@ -1236,6 +1261,12 @@ static void qxl_hard_reset(PCIQXLDevice *d, int
> loadvm)
> qemu_spice_create_host_memslot(&d->ssd);
> qxl_soft_reset(d);
>
> + if (d->migration_blocker) {
> + migrate_del_blocker(d->migration_blocker);
> + error_free(d->migration_blocker);
> + d->migration_blocker = NULL;
> + }
> +
> if (startstop) {
> qemu_spice_display_start();
> }
> --
> 2.9.3
>
> --
Marc-André Lureau