MIPS: Avoid potential hazard on Context register
set_saved_sp reads Context register. Avoid reading stale value from
earlier incomplete write.
Issue found and fixed for head.S by Chris Dearman <chris@mips.com>.
Signed-off-by: Chris Dearman <chris@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/head.S b/arch/mips/kernel/head.S
index 531ce7b..ea695d9 100644
--- a/arch/mips/kernel/head.S
+++ b/arch/mips/kernel/head.S
@@ -191,6 +191,7 @@
/* Set the SP after an empty pt_regs. */
PTR_LI sp, _THREAD_SIZE - 32 - PT_SIZE
PTR_ADDU sp, $28
+ back_to_back_c0_hazard
set_saved_sp sp, t0, t1
PTR_SUBU sp, 4 * SZREG # init stack pointer