Re: [PATCH-for-9.2? v2 1/2] hw/display/vga: Do not reset 'big_endian_fb' in vga_common_reset()

[Gerd Hoffmann]

  Hi,

> For bochs and ati, there's a register to configure it as well, so there
> *may* be an expectation that it gets reset there, I'm less certain.

The default is there for backward compatibility reasons and it should
default to machine byte order so you get something working even in case
the guest does not explicitly set the byte order via register.  Which
should be increasingly rare these days, the register was added in
(checking git log) 2014: commit b5682aa4ca79 ("vga-pci: add qext region
to mmio")

The only case I'm aware of where the byte order is actually switched is
booting a ppc64le guest in a pseries machine, where the opal firmware
runs in bigendian mode and the linux kernel runs in little endian mode.

So here the changed reset behavior could actually make a difference, but
you will only notice if the opal firmware does *not* set the byte order
register.

take care,
  Gerd