At present it is not possible to execution 64-bit code without installing an entire new Global Descriptor Table. This is inconvenient since kvm does not seem to like switching into long mode with a new table.
It isn't actually necessary, since we can just extend the existing table. Add some new entries to this effect.
Signed-off-by: Simon Glass sjg@chromium.org ---
arch/x86/cpu/i386/cpu.c | 3 +++ arch/x86/include/asm/processor.h | 5 ++++- 2 files changed, 7 insertions(+), 1 deletion(-)
diff --git a/arch/x86/cpu/i386/cpu.c b/arch/x86/cpu/i386/cpu.c index a51a24498a7..3bbad3b2eca 100644 --- a/arch/x86/cpu/i386/cpu.c +++ b/arch/x86/cpu/i386/cpu.c @@ -160,6 +160,9 @@ void arch_setup_gd(gd_t *new_gd)
gdt_addr[X86_GDT_ENTRY_16BIT_FLAT_CS] = GDT_ENTRY(0x809b, 0, 0xfffff); gdt_addr[X86_GDT_ENTRY_16BIT_FLAT_DS] = GDT_ENTRY(0x8093, 0, 0xfffff); + gdt_addr[X86_GDT_ENTRY_64BIT_CS] = GDT_ENTRY(0xaf9b, 0, 0xfffff); + gdt_addr[X86_GDT_ENTRY_64BIT_TS1] = GDT_ENTRY(0x8980, 0, 0xfffff); + gdt_addr[X86_GDT_ENTRY_64BIT_TS2] = 0;
load_gdt(gdt_addr, X86_GDT_NUM_ENTRIES); load_ds(X86_GDT_ENTRY_32BIT_DS); diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index d7b68367861..ad8240be387 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -18,7 +18,10 @@ #define X86_GDT_ENTRY_16BIT_DS 6 #define X86_GDT_ENTRY_16BIT_FLAT_CS 7 #define X86_GDT_ENTRY_16BIT_FLAT_DS 8 -#define X86_GDT_NUM_ENTRIES 9 +#define X86_GDT_ENTRY_64BIT_CS 9 +#define X86_GDT_ENTRY_64BIT_TS1 10 +#define X86_GDT_ENTRY_64BIT_TS2 11 +#define X86_GDT_NUM_ENTRIES 12
#define X86_GDT_SIZE (X86_GDT_NUM_ENTRIES * X86_GDT_ENTRY_SIZE)