diff options
| author | Kevin O'Connor <kevin@koconnor.net> | 2014-04-06 18:48:39 -0400 |
|---|---|---|
| committer | Kevin O'Connor <kevin@koconnor.net> | 2014-04-11 11:26:23 -0400 |
| commit | 8f82a4fb4aff536e48653c2b10a36018ea77e29e (patch) | |
| tree | ae0cf732c501e3dccf7c2236cf0feba3e83686bc /vgasrc | |
| parent | f6b44b81e61be2e03a9e296dd592cbf4d78a336b (diff) | |
| download | qemu-seabios-8f82a4fb4aff536e48653c2b10a36018ea77e29e.tar.gz | |
vgabios: PMM scan was incorrectly depending on a zero %ds segment.
Make sure the PMM scanning code uses the GET_FARVAR macro. (The
existing code only worked because SeaBIOS happens to call the vgabios
in bigreal mode with %ds == %ss = 0.) Also, the scan doesn't require
bigreal mode - use accesses relative to the SEG_BIOS segment so that
the scan can work in regular real mode.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
Diffstat (limited to 'vgasrc')
| -rw-r--r-- | vgasrc/vgainit.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/vgasrc/vgainit.c b/vgasrc/vgainit.c index 33b8eb9..6d9a224 100644 --- a/vgasrc/vgainit.c +++ b/vgasrc/vgainit.c @@ -60,14 +60,14 @@ allocate_extra_stack(void) { if (!CONFIG_VGA_ALLOCATE_EXTRA_STACK) return; - void *pmmscan = (void*)BUILD_BIOS_ADDR; - for (; pmmscan < (void*)BUILD_BIOS_ADDR+BUILD_BIOS_SIZE; pmmscan+=16) { - struct pmmheader *pmm = pmmscan; - if (pmm->signature != PMM_SIGNATURE) + u32 pmmscan; + for (pmmscan=0; pmmscan < BUILD_BIOS_SIZE; pmmscan+=16) { + struct pmmheader *pmm = (void*)pmmscan; + if (GET_FARVAR(SEG_BIOS, pmm->signature) != PMM_SIGNATURE) continue; - if (checksum_far(0, pmm, pmm->length)) + if (checksum_far(SEG_BIOS, pmm, GET_FARVAR(SEG_BIOS, pmm->length))) continue; - struct segoff_s entry = pmm->entry; + struct segoff_s entry = GET_FARVAR(SEG_BIOS, pmm->entry); dprintf(1, "Attempting to allocate VGA stack via pmm call to %04x:%04x\n" , entry.seg, entry.offset); u16 res1, res2; |