Split load_gdt_tss() functionality into: 1. Load gdt/tss 2. Setup segments in 64-bit mode and update %cs via far-return and move load_gdt_tss() to desc.c to share this code between EFI and non-EFI tests. Signed-off-by: Varad Gautam <varad.gautam@xxxxxxxx> --- lib/x86/desc.c | 6 ++++++ lib/x86/desc.h | 1 + lib/x86/setup.c | 4 +++- x86/efi/efistart64.S | 11 ++--------- 4 files changed, 12 insertions(+), 10 deletions(-) diff --git a/lib/x86/desc.c b/lib/x86/desc.c index 049adeb..3b1208b 100644 --- a/lib/x86/desc.c +++ b/lib/x86/desc.c @@ -362,6 +362,12 @@ void set_gdt_entry(int sel, unsigned long base, u32 limit, u8 type, u8 flags) #endif } +void load_gdt_tss(size_t tss_offset) +{ + lgdt(&gdt_descr); + ltr(tss_offset); +} + #ifndef __x86_64__ void set_gdt_task_gate(u16 sel, u16 tss_sel) { diff --git a/lib/x86/desc.h b/lib/x86/desc.h index ae0928f..83a16dd 100644 --- a/lib/x86/desc.h +++ b/lib/x86/desc.h @@ -222,6 +222,7 @@ void set_idt_entry(int vec, void *addr, int dpl); void set_idt_sel(int vec, u16 sel); void set_idt_dpl(int vec, u16 dpl); void set_gdt_entry(int sel, unsigned long base, u32 limit, u8 access, u8 gran); +void load_gdt_tss(size_t tss_offset); void set_intr_alt_stack(int e, void *fn); void print_current_tss_info(void); handler handle_exception(u8 v, handler fn); diff --git a/lib/x86/setup.c b/lib/x86/setup.c index 94e9f86..7dd6677 100644 --- a/lib/x86/setup.c +++ b/lib/x86/setup.c @@ -170,7 +170,7 @@ void setup_multiboot(struct mbi_bootinfo *bi) #ifdef CONFIG_EFI /* From x86/efi/efistart64.S */ -extern void load_gdt_tss(size_t tss_offset); +extern void setup_segments64(void); static efi_status_t setup_memory_allocator(efi_bootinfo_t *efi_bootinfo) { @@ -275,6 +275,8 @@ static void setup_gdt_tss(void) /* 64-bit setup_tss does not use the stacktop argument. */ tss_offset = setup_tss(NULL); load_gdt_tss(tss_offset); + + setup_segments64(); } efi_status_t setup_efi(efi_bootinfo_t *efi_bootinfo) diff --git a/x86/efi/efistart64.S b/x86/efi/efistart64.S index ea3d1c0..8eadca5 100644 --- a/x86/efi/efistart64.S +++ b/x86/efi/efistart64.S @@ -26,15 +26,8 @@ ptl4: .code64 .text -.globl load_gdt_tss -load_gdt_tss: - /* Load GDT */ - lgdt gdt_descr(%rip) - - /* Load TSS */ - mov %rdi, %rax - ltr %ax - +.globl setup_segments64 +setup_segments64: /* Update data segments */ mov $0x10, %ax /* 3rd entry in gdt64: 32/64-bit data segment */ mov %ax, %ds -- 2.32.0