diff options
Diffstat (limited to 'src/kernel/arch/amd64')
| -rw-r--r-- | src/kernel/arch/amd64/sysenter.s | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/src/kernel/arch/amd64/sysenter.s b/src/kernel/arch/amd64/sysenter.s index c1af69f..8d91c4a 100644 --- a/src/kernel/arch/amd64/sysenter.s +++ b/src/kernel/arch/amd64/sysenter.s @@ -2,6 +2,7 @@ .set SEG_r0code, 1 .set SEG_r3code32, 3 .set SEG_r3data, 4 +.set SEG_r3code, 5 .set IA32_STAR, 0xC0000081 .set IA32_LSTAR, 0xC0000082 @@ -40,16 +41,22 @@ stored_rsp: pagedir_current: .skip 8 +// temporarily used for IRET + .skip 8 + .skip 8 + .skip 8 + .skip 8 + .skip 8 +dumb_stack: + .global _sysexit_real .type _sysexit_real, @function _sysexit_real: - /* TODO check if SYSRET correctly sets segments mov $(SEG_r3data << 3 | 3), %ax mov %ax, %ds mov %ax, %es mov %ax, %fs mov %ax, %gs - */ /* The state image referenced with an FXRSTOR instruction must have * been saved using an FXSAVE instruction or be in the same format @@ -81,8 +88,14 @@ _sysexit_real: // enable paging mov (pagedir_current), %rsp mov %rsp, %cr3 - mov (stored_rsp), %rsp - sysretq + + mov $dumb_stack, %rsp + push $(SEG_r3data << 3 | 3) /* SS */ + push (stored_rsp) /* SP */ + push %r11 /* FLAGS */ + push $(SEG_r3code << 3 | 3) /* CS */ + push %rcx /* IP */ + iretq sysenter_stage1: cli |