UefiCpuPkg/CpuExceptionHandlerLib: Setup single step in #PF handler

[mirror_edk2.git] / UefiCpuPkg / Library / CpuExceptionHandlerLib / Ia32 / ExceptionTssEntryAsm.nasm

diff --git a/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ExceptionTssEntryAsm.nasm b/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ExceptionTssEntryAsm.nasm
index 62bcedea1a29485ab68dae74c4fc104e9f7f82b4..7aac29c7e76d9527635f039fe079102b47a5ecac 100644 (file)
--- a/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ExceptionTssEntryAsm.nasm
+++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ExceptionTssEntryAsm.nasm
@@ -355,10 +355,8 @@ o16 mov     [ecx + IA32_TSS._SS], ax
     movzx  ebx, word [ecx + IA32_TSS._CS]\r
     mov    [eax - 0x8], ebx                      ; create CS in old stack\r
     mov    ebx, dword [ecx + IA32_TSS.EFLAGS]\r
-    bts    ebx, 8\r
+    bts    ebx, 8                                ; Set TF\r
     mov    [eax - 0x4], ebx                      ; create eflags in old stack\r
-    mov    dword [ecx + IA32_TSS.EFLAGS], ebx    ; update eflags in old TSS\r
-    mov    eax, dword [ecx + IA32_TSS._ESP]      ; Get old stack pointer\r
     sub    eax, 0xc                              ; minus 12 byte\r
     mov    dword [ecx + IA32_TSS._ESP], eax      ; Set new stack pointer\r
 \r