From 0f788893a8bbad95edcdf3db5009642633dee7dc Mon Sep 17 00:00:00 2001 From: Kevin O'Connor Date: Sun, 25 Jul 2010 14:04:01 -0400 Subject: Avoid code addresses >64K in big real mode. Kvm has some limitations with code addresses in big real mode, so avoid doing that. --- src/misc.c | 4 ++-- src/romlayout.S | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/src/misc.c b/src/misc.c index 354df875..108c3326 100644 --- a/src/misc.c +++ b/src/misc.c @@ -156,8 +156,8 @@ u64 rombios32_gdt[] VAR16VISIBLE __aligned(8) = { GDT_LIMIT(BUILD_BIOS_SIZE-1) | GDT_CODE | GDT_BASE(BUILD_BIOS_ADDR), // 16 bit data segment base=0x0 limit=0xffff (SEG32_MODE16_DS) GDT_LIMIT(0x0ffff) | GDT_DATA, - // 16 bit code segment base=0 limit=0xffffffff (SEG32_MODE16BIG_CS) - GDT_LIMIT(0xfffff) | GDT_CODE | GDT_G, + // 16 bit code segment base=0xf0000 limit=0xffffffff (SEG32_MODE16BIG_CS) + GDT_LIMIT(0xfffff) | GDT_CODE | GDT_G | GDT_BASE(BUILD_BIOS_ADDR), // 16 bit data segment base=0 limit=0xffffffff (SEG32_MODE16BIG_DS) GDT_LIMIT(0xfffff) | GDT_DATA | GDT_G, }; diff --git a/src/romlayout.S b/src/romlayout.S index 54e5a4d2..a4695963 100644 --- a/src/romlayout.S +++ b/src/romlayout.S @@ -105,7 +105,7 @@ transition16big: movw %ax, %fs movw %ax, %gs - ljmpl $SEG32_MODE16BIG_CS, $(BUILD_BIOS_ADDR + 1f) + ljmpw $SEG32_MODE16BIG_CS, $1f .code16gcc 1: -- cgit