diff options
Diffstat (limited to 'src/arch')
| -rw-r--r-- | src/arch/i386/transitions/librm.S | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/src/arch/i386/transitions/librm.S b/src/arch/i386/transitions/librm.S index 6dc6b4fd8..5299841c9 100644 --- a/src/arch/i386/transitions/librm.S +++ b/src/arch/i386/transitions/librm.S @@ -496,8 +496,10 @@ EXPORT(prot_call): movl $SIZEOF_REAL_MODE_REGS, %ecx subl %ecx, %esp movl %esp, %edi + pushl %esi cld - rep movsb + rep movsb + popl %edi /* %edi = phys addr of RM copy of rm_regs */ /* Switch to virtual addresses. */ call 1f @@ -522,7 +524,18 @@ EXPORT(prot_call): /* Switch to physical addresses, discard PM register store */ lcall $VIRTUAL_CS, $_virt_to_phys - addl $SIZEOF_REAL_MODE_REGS+4, %esp /* also discard lcall seg */ + popl %eax /* discard */ + + /* Copy rm_regs from PM stack to RM stack, and remove rm_regs + * from PM stack. (%edi still contains physical address of + * rm_regs on RM stack from earlier, since C code preserves + * %edi). + */ + movl %esp, %esi + movl $SIZEOF_REAL_MODE_REGS, %ecx + cld + rep movsb + movl %esi, %esp /* remove rm_regs from PM stack */ /* Switch to real mode */ call prot_to_real |