[PATCH 4.9 033/172] MIPS: head: Reorder instructions missing a delay slot
From: Greg Kroah-Hartman
Date: Mon Jul 03 2017 - 10:38:19 EST
4.9-stable review patch. If anyone has any objections, please let me know.
From: Karl Beldan <karl.beldan@xxxxxxxxx>
commit 25d8b92e0af75d72ce8b99e63e5a449cc0888efa upstream.
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")
Signed-off-by: Karl Beldan <karl.beldan+oss@xxxxxxxxx>
Reviewed-by: James Hogan <james.hogan@xxxxxxxxxx>
Cc: Jonas Gorski <jogo@xxxxxxxxxxx>
Signed-off-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
arch/mips/kernel/head.S | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
@@ -106,8 +106,8 @@ NESTED(kernel_entry, 16, sp) # kernel
beq t0, t1, dtb_found
li t1, -2
- beq a0, t1, dtb_found
move t2, a1
+ beq a0, t1, dtb_found
li t2, 0