verify_cpu clobbers BX and DI. In case we have to return error, we need
to preserve them to respect 32-bit calling convention.
Signed-off-by: Arvind Sankar <[email protected]>
---
arch/x86/boot/compressed/head_64.S | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index 8105e8348607..920daf62dac2 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -660,7 +660,11 @@ SYM_DATA(efi_is64, .byte 1)
SYM_FUNC_START(efi32_pe_entry)
pushl %ebp
+ pushl %ebx
+ pushl %edi
call verify_cpu // check for long mode support
+ popl %edi
+ popl %ebx
testl %eax, %eax
movl $0x80000003, %eax // EFI_UNSUPPORTED
jnz 3f
--
2.24.1