From: David Woodhouse <d...@amazon.co.uk>
If the no-real-mode flag is set, don't go there at all. This is a prelude
to not even putting it there in the first place.
Signed-off-by: David Woodhouse <d...@amazon.co.uk>
---
xen/arch/x86/boot/head.S | 10 ++++++++++
xen/arch/x86/boot/trampoline.S | 4 ----
2 files changed, 10 insertions(+), 4 deletions(-)
diff --git a/xen/arch/x86/boot/head.S b/xen/arch/x86/boot/head.S
index 26b680521d..d303379083 100644
--- a/xen/arch/x86/boot/head.S
+++ b/xen/arch/x86/boot/head.S
@@ -727,7 +727,17 @@ trampoline_setup:
/* Switch to low-memory stack which lives at the end of trampoline
region. */
mov sym_fs(trampoline_phys),%edi
lea TRAMPOLINE_SPACE+TRAMPOLINE_STACK_SPACE(%edi),%esp
+ cmpb $0, sym_fs(skip_realmode)
+ jz 1f
+ /* If no-real-mode, jump straight to trampoline_protmode_entry */
+ lea trampoline_protmode_entry-trampoline_start(%edi),%eax
+ /* EBX == 0 indicates we are the BP (Boot Processor). */
+ xor %ebx,%ebx
+ jmp 2f
+1:
+ /* Go via 16-bit code in trampoline_boot_cpu_entry */
lea trampoline_boot_cpu_entry-trampoline_start(%edi),%eax
+2:
pushl $BOOT_CS32
push %eax
diff --git a/xen/arch/x86/boot/trampoline.S b/xen/arch/x86/boot/trampoline.S
index 7c6a2328d2..429a088b19 100644
--- a/xen/arch/x86/boot/trampoline.S
+++ b/xen/arch/x86/boot/trampoline.S
@@ -194,9 +194,6 @@ gdt_48: .word 6*8-1
.code32
trampoline_boot_cpu_entry:
- cmpb $0,bootsym_rel(skip_realmode,5)
- jnz .Lskip_realmode
-
/* Load pseudo-real-mode segments. */
mov $BOOT_PSEUDORM_DS,%eax
mov %eax,%ds
@@ -276,7 +273,6 @@ trampoline_boot_cpu_entry:
mov %eax,%gs
mov %eax,%ss
-.Lskip_realmode:
/* EBX == 0 indicates we are the BP (Boot Processor). */
xor %ebx,%ebx
--
2.21.0
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
