On 12/07/2013 01:52 AM, Alexander Graf wrote: > When we're running in non-64bit mode with qemu-system-x86_64 we can > still end up with virtual addresses that are above the 32bit boundary > if a segment offset is set up. > > GNU Hurd does exactly that. It sets the segment offset to 0x80000000 and > puts its EIP value to 0x8xxxxxxx to access low memory. > > This doesn't hit us when we enable paging, as there we just mask away the > unused bits. But with real mode, we assume that vaddr == paddr which is > wrong in this case. Real hardware wraps the virtual address around at the > 32bit boundary. So let's do the same. > > This fixes booting GNU Hurd in qemu-system-x86_64 for me. > > Reported-by: Michael Tokarev <m...@tls.msk.ru> > Signed-off-by: Alexander Graf <ag...@suse.de> > --- > target-i386/helper.c | 6 ++++++ > 1 file changed, 6 insertions(+)
Reviewed-by: Richard Henderson <r...@twiddle.net> r~
