diff options
Diffstat (limited to 'src/arch/x86/c_start.S')
| -rw-r--r-- | src/arch/x86/c_start.S | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/src/arch/x86/c_start.S b/src/arch/x86/c_start.S index 9a64fa6092..29d3a538b4 100644 --- a/src/arch/x86/c_start.S +++ b/src/arch/x86/c_start.S @@ -349,7 +349,9 @@ gdt: /* selgdt 0x10, flat code segment */ .word 0xffff, 0x0000 - .byte 0x00, 0x9b, 0xcf, 0x00 /* G=1 and 0x0f, So we get 4Gbytes for limit */ + .byte 0x00, 0x9b, 0xcf, 0x00 /* G=1 and 0x0f, So we get 4Gbytes for + * limit + */ /* selgdt 0x18, flat data segment */ .word 0xffff, 0x0000 @@ -377,11 +379,15 @@ gdt: /* selgdt 0x38, flat data segment 16 bit */ .word 0x0000, 0x0000 /* dummy */ - .byte 0x00, 0x93, 0x8f, 0x00 /* G=1 and 0x0f, So we get 4Gbytes for limit */ + .byte 0x00, 0x93, 0x8f, 0x00 /* G=1 and 0x0f, So we get 4Gbytes for + * limit + */ /* selgdt 0x40, flat code segment 16 bit */ .word 0xffff, 0x0000 - .byte 0x00, 0x9b, 0x8f, 0x00 /* G=1 and 0x0f, So we get 4Gbytes for limit */ + .byte 0x00, 0x9b, 0x8f, 0x00 /* G=1 and 0x0f, So we get 4Gbytes for + * limit + */ #ifdef __x86_64__ /* selgdt 0x48, flat x64 code segment */ @@ -407,14 +413,16 @@ SetCodeSelector: # use iret to jump to a 64-bit offset in a new code segment # iret will pop cs:rip, flags, then ss:rsp mov %ss, %ax # need to push ss.. - push %rax # push ss instuction not valid in x64 mode, so use ax + push %rax # push ss instuction not valid in x64 mode, + # so use ax push %rsp pushfq push %rcx # cx is code segment selector from caller mov $setCodeSelectorLongJump, %rax push %rax - # the iret will continue at next instruction, with the new cs value loaded + # the iret will continue at next instruction, with the new cs value + # loaded iretq setCodeSelectorLongJump: |