[PATCH] MIPS: head: Reorder instructions missing a delay slot

From: Karl Beldan
Date: Tue Jun 27 2017 - 15:11:34 EST


In this sequence the 'move' is assumed in the delay slot of the 'beq',
but head.S is in reorder mode and the former gets pushed one 'nop'
farther by the assembler.

The corrected behavior made booting with an UHI supplied dtb erratic.

Fixes: 15f37e158892 ("MIPS: store the appended dtb address in a variable")
Cc: <stable@xxxxxxxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: Jonas Gorski <jogo@xxxxxxxxxxx>
Signed-off-by: Karl Beldan <karl.beldan+oss@xxxxxxxxx>
---
arch/mips/kernel/head.S | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/mips/kernel/head.S b/arch/mips/kernel/head.S
index cf05220..d1bb506 100644
--- a/arch/mips/kernel/head.S
+++ b/arch/mips/kernel/head.S
@@ -106,8 +106,8 @@ NESTED(kernel_entry, 16, sp) # kernel entry point
beq t0, t1, dtb_found
#endif
li t1, -2
- beq a0, t1, dtb_found
move t2, a1
+ beq a0, t1, dtb_found

li t2, 0
dtb_found:
--
2.10.1