On 11/19/21 10:58, Thomas Huth wrote: > On 19/11/2021 10.49, Philippe Mathieu-Daudé wrote: >> On 11/19/21 09:21, Mark Cave-Ayland wrote: >>> On 18/11/2021 19:20, Philippe Mathieu-Daudé wrote: >>> >>>> Commit 7852a77f598 fixed creating multiple TYPE_ISA_VGA devices, >>>> generalize the fix to all VGA devices. >>>> >>>> See https://gitlab.com/qemu-project/qemu/-/issues/44 >>>> >>>> Philippe Mathieu-Daudé (2): >>>> hw/display: Add Error* handle to vga_common_init() >>>> hw/display: Do not allow multiple identical VGA devices >>>> >>>> hw/display/vga_int.h | 2 +- >>>> hw/display/ati.c | 4 +++- >>>> hw/display/cirrus_vga.c | 4 +++- >>>> hw/display/cirrus_vga_isa.c | 4 +++- >>>> hw/display/qxl.c | 4 +++- >>>> hw/display/vga-isa-mm.c | 3 ++- >>>> hw/display/vga-isa.c | 11 ++--------- >>>> hw/display/vga-pci.c | 8 ++++++-- >>>> hw/display/vga.c | 17 ++++++++++++++++- >>>> hw/display/virtio-vga.c | 4 +++- >>>> hw/display/vmware_vga.c | 2 +- >>>> 11 files changed, 43 insertions(+), 20 deletions(-) >>> >>> Hi Phil, >>> >>> I don't think this is correct for non-ISA devices: for example years ago >>> I had a PC running Windows 98SE with 2 identical PCI graphics cards >>> configured in dual-head mode. >>> >>> IIRC the BIOS would bring up the first graphics card and configure it to >>> use the legacy ISA VGA ioports for compatibility, and then once the main >>> OS drivers loaded both cards were switched to PCI mode and configured >>> using the BARs as normal. >> >> The problem here is QEMU technical debt, not the hardware. >> >> When vga_common_init() calls memory_region_init_ram_nomigrate() >> with obj=NULL, "vga.vram" is registered as a QOM singleton. >> >> Updating it would >> 1/ require non-QOM devices to be QOM'ified > > So sounds like that's the right way to go here. > >> and 2/ break migration unless using HPFM which I don't master. > > What's HPFM?
Hocus Pocus Freakin' Magic
