movw %cx, %es\r
movw %cx, %fs\r
movw %cx, %gs\r
- movl %eax, %cr0\r
- movl %ebp, %cr4 # real mode starts at next instruction\r
+ movl %eax, %cr0 # real mode starts at next instruction\r
+ # which (per SDM) *must* be a far JMP.\r
+ ljmpw $0,$0 # will be filled in by InternalAsmThunk16\r
+L_Base: # to point here.\r
+ movl %ebp, %cr4\r
movw %si, %ss # set up 16-bit stack segment\r
xchgl %ebx, %esp # set up 16-bit stack pointer\r
- calll L_Base # push eip\r
-L_Base:\r
- popl %ebp # ebp <- offset L_Base\r
- push (IA32_REGS_SIZE + 2)(%esp)\r
- lea (L_RealMode - L_Base)(%bp), %ax\r
- push %ax\r
- lret\r
\r
-L_RealMode:\r
- mov %dx, %cs:(SavedSs - L_Base)(%bp)\r
- mov %ebx, %cs:(SavedEsp - L_Base)(%bp)\r
- lidtl %cs:(_16Idtr - L_Base)(%bp)\r
+ movw IA32_REGS_SIZE(%esp), %bp # get BackToUserCode address from stack\r
+ mov %dx, %cs:(SavedSs - ASM_PFX(BackFromUserCode))(%bp)\r
+ mov %ebx, %cs:(SavedEsp - ASM_PFX(BackFromUserCode))(%bp)\r
+ lidtl %cs:(_16Idtr - ASM_PFX(BackFromUserCode))(%bp)\r
popal\r
pop %ds\r
pop %es\r
lea (ASM_PFX(BackFromUserCode) - ASM_PFX(m16Start))(%ecx), %ecx\r
movw %cx, %ax\r
stosl # [edi] <- return address of user code\r
+ addl $(L_Base - ASM_PFX(BackFromUserCode)), %eax\r
+ movl %eax, (L_Base - SavedCr0 - 4)(%edx)\r
sgdtl (SavedGdt - SavedCr0)(%edx)\r
sidtl 0x24(%esp)\r
movl %cr0, %eax\r