On Mon, Mar 9, 2020 at 3:00 AM Gerd Hoffmann <kra...@redhat.com> wrote: > > The bochs-display mmio bar has some sub-regions with the actual hardware > registers. What happens when the guest access something outside those > regions depends on the archirecture. On x86 those reads succeed (and > return 0xff I think). On risc-v qemu aborts. > > This patch adds handlers for the parent region, to make the wanted > behavior explicit and to make things consistent across architectures. > > v2: > - use existing unassigned_io_ops. > - also cover stdvga. > > Cc: Alistair Francis <alistai...@gmail.com> > Signed-off-by: Gerd Hoffmann <kra...@redhat.com>
+ QEMU stable. Can this be back ported to 5.0? Without this patch the bochs device doesn't work with RISC-V. Alistair > --- > hw/display/bochs-display.c | 4 ++-- > hw/display/vga-pci.c | 8 ++++---- > 2 files changed, 6 insertions(+), 6 deletions(-) > > diff --git a/hw/display/bochs-display.c b/hw/display/bochs-display.c > index 62085f9fc063..70eb619ef424 100644 > --- a/hw/display/bochs-display.c > +++ b/hw/display/bochs-display.c > @@ -284,8 +284,8 @@ static void bochs_display_realize(PCIDevice *dev, Error > **errp) > memory_region_init_io(&s->qext, obj, &bochs_display_qext_ops, s, > "qemu extended regs", PCI_VGA_QEXT_SIZE); > > - memory_region_init(&s->mmio, obj, "bochs-display-mmio", > - PCI_VGA_MMIO_SIZE); > + memory_region_init_io(&s->mmio, obj, &unassigned_io_ops, NULL, > + "bochs-display-mmio", PCI_VGA_MMIO_SIZE); > memory_region_add_subregion(&s->mmio, PCI_VGA_BOCHS_OFFSET, &s->vbe); > memory_region_add_subregion(&s->mmio, PCI_VGA_QEXT_OFFSET, &s->qext); > > diff --git a/hw/display/vga-pci.c b/hw/display/vga-pci.c > index b34632467399..6b9db86e363c 100644 > --- a/hw/display/vga-pci.c > +++ b/hw/display/vga-pci.c > @@ -249,8 +249,8 @@ static void pci_std_vga_realize(PCIDevice *dev, Error > **errp) > > /* mmio bar for vga register access */ > if (d->flags & (1 << PCI_VGA_FLAG_ENABLE_MMIO)) { > - memory_region_init(&d->mmio, NULL, "vga.mmio", > - PCI_VGA_MMIO_SIZE); > + memory_region_init_io(&d->mmio, OBJECT(dev), &unassigned_io_ops, > NULL, > + "vga.mmio", PCI_VGA_MMIO_SIZE); > > if (d->flags & (1 << PCI_VGA_FLAG_ENABLE_QEXT)) { > qext = true; > @@ -285,8 +285,8 @@ static void pci_secondary_vga_realize(PCIDevice *dev, > Error **errp) > s->con = graphic_console_init(DEVICE(dev), 0, s->hw_ops, s); > > /* mmio bar */ > - memory_region_init(&d->mmio, OBJECT(dev), "vga.mmio", > - PCI_VGA_MMIO_SIZE); > + memory_region_init_io(&d->mmio, OBJECT(dev), &unassigned_io_ops, NULL, > + "vga.mmio", PCI_VGA_MMIO_SIZE); > > if (d->flags & (1 << PCI_VGA_FLAG_ENABLE_QEXT)) { > qext = true; > -- > 2.18.2 >