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-rw-r--r--arch/x86/boot/compressed/head_32.S54
1 files changed, 40 insertions, 14 deletions
diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
index cbed1407a5cd..d6b8aa4c986c 100644
--- a/arch/x86/boot/compressed/head_32.S
+++ b/arch/x86/boot/compressed/head_32.S
@@ -30,6 +30,33 @@
#include <asm/boot.h>
#include <asm/asm-offsets.h>
+/*
+ * Adjust our own GOT
+ *
+ * The relocation base must be in %ebx
+ *
+ * It is safe to call this macro more than once, because in some of the
+ * code paths multiple invocations are inevitable, e.g. via the efi*
+ * entry points.
+ *
+ * Relocation is only performed the first time.
+ */
+.macro FIXUP_GOT
+ cmpb $1, got_fixed(%ebx)
+ je 2f
+
+ leal _got(%ebx), %edx
+ leal _egot(%ebx), %ecx
+1:
+ cmpl %ecx, %edx
+ jae 2f
+ addl %ebx, (%edx)
+ addl $4, %edx
+ jmp 1b
+2:
+ movb $1, got_fixed(%ebx)
+.endm
+
__HEAD
ENTRY(startup_32)
#ifdef CONFIG_EFI_STUB
@@ -56,6 +83,9 @@ ENTRY(efi_pe_entry)
add %esi, 88(%eax)
pushl %eax
+ movl %esi, %ebx
+ FIXUP_GOT
+
call make_boot_params
cmpl $0, %eax
je fail
@@ -81,6 +111,10 @@ ENTRY(efi32_stub_entry)
leal efi32_config(%esi), %eax
add %esi, 88(%eax)
pushl %eax
+
+ movl %esi, %ebx
+ FIXUP_GOT
+
2:
call efi_main
cmpl $0, %eax
@@ -190,19 +224,7 @@ relocated:
shrl $2, %ecx
rep stosl
-/*
- * Adjust our own GOT
- */
- leal _got(%ebx), %edx
- leal _egot(%ebx), %ecx
-1:
- cmpl %ecx, %edx
- jae 2f
- addl %ebx, (%edx)
- addl $4, %edx
- jmp 1b
-2:
-
+ FIXUP_GOT
/*
* Do the decompression, and jump to the new kernel..
*/
@@ -225,8 +247,12 @@ relocated:
xorl %ebx, %ebx
jmp *%eax
-#ifdef CONFIG_EFI_STUB
.data
+/* Have we relocated the GOT? */
+got_fixed:
+ .byte 0
+
+#ifdef CONFIG_EFI_STUB
efi32_config:
.fill 11,8,0
.long efi_call_phys
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