[PATCH] powerpc: Fixed the bug of duplicate copying

[Jinglin Wen]

Fixed the issue where the kernel, when booting from address 0, had
code incorrectly duplicated to address 0.

Signed-off-by: Jinglin Wen <jinglin.wen at shingroup.cn>
---
 arch/powerpc/kernel/head_64.S | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index 4690c219bfa4..6c73551bdc50 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -647,7 +647,9 @@ __after_prom_start:
  * Note: This process overwrites the OF exception vectors.
  */
 	LOAD_REG_IMMEDIATE(r3, PAGE_OFFSET)
-	mr.	r4,r26			/* In some cases the loader may  */
+	tophys(r4,r26)
+	cmplwi	cr0,r4,0	/* runtime base addr is zero */
+	mr	r4,r26			/* In some cases the loader may */
 	beq	9f			/* have already put us at zero */
 	li	r6,0x100		/* Start offset, the first 0x100 */
 					/* bytes were copied earlier.	 */
-- 
2.25.1