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| author | Michael Brown | 2005-04-09 15:56:33 +0200 |
|---|---|---|
| committer | Michael Brown | 2005-04-09 15:56:33 +0200 |
| commit | a800e9657d69c524cb12570a2391e3803cbafab5 (patch) | |
| tree | 2feafa9b19d301a6cb8d529753937f6fc2d26b51 /src/arch/i386/transitions/librm.S | |
| parent | Add relocate.h (diff) | |
| download | ipxe-a800e9657d69c524cb12570a2391e3803cbafab5.tar.gz ipxe-a800e9657d69c524cb12570a2391e3803cbafab5.tar.xz ipxe-a800e9657d69c524cb12570a2391e3803cbafab5.zip | |
PM function called by prot_call() should be allowed to modifying
registers returned to RM code.
Diffstat (limited to 'src/arch/i386/transitions/librm.S')
| -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 6dc6b4fd..5299841c 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 |