MdePkg NASM Thunk16: Work around NASM 2.09.04 - 2.10rc1 bug

Without this change, NASM 2.09.04 will hang with OVMF+CSM on both IA32
and X64.

Tested on OVMF+CSM on GCC49 with NASM 2.07, 2.09.04 and 2.11.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16058 6f19259b-4bc3-4df7-8a09-765794883524
This commit is contained in:
Jordan Justen 2014-09-04 15:17:48 +00:00 committed by jljusten
parent 49d9b71df2
commit eabcdf3a34
2 changed files with 10 additions and 2 deletions

View File

@ -85,7 +85,11 @@ _BackFromUserCode:
BITS 16
push ss
push cs
o32 call dword .Base ; push eip
;
; Note: We can't use o32 on the next instruction because of a bug
; in NASM 2.09.04 through 2.10rc1.
;
call dword .Base ; push eip
.Base:
pushfd
cli ; disable interrupts

View File

@ -83,7 +83,11 @@ _BackFromUserCode:
BITS 16
push ss
push cs
o32 call dword .Base ; push eip
;
; Note: We can't use o32 on the next instruction because of a bug
; in NASM 2.09.04 through 2.10rc1.
;
call dword .Base ; push eip
.Base:
push dword 0 ; reserved high order 32 bits of EFlags
pushfd