[PATCH RFC rebase 3/9] powerpc/64: Use barrier_nospec in syscall entry

[Michal Suchanek]

On powerpc syscall entry is done in assembly so patch in an explicit
barrier_nospec.

Signed-off-by: Michal Suchanek <msuchanek@xxxxxxx>
---
 arch/powerpc/kernel/entry_64.S | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 2cb5109a7ea3..7bfc4cf48af2 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -36,6 +36,7 @@
 #include <asm/context_tracking.h>
 #include <asm/tm.h>
 #include <asm/ppc-opcode.h>
+#include <asm/barrier.h>
 #include <asm/export.h>
 #ifdef CONFIG_PPC_BOOK3S
 #include <asm/exception-64s.h>
@@ -159,6 +160,7 @@ system_call:			/* label this so stack traces look sane */
 	andi.	r11,r10,_TIF_SYSCALL_DOTRACE
 	bne	.Lsyscall_dotrace		/* does not return */
 	cmpldi	0,r0,NR_syscalls
+	barrier_nospec
 	bge-	.Lsyscall_enosys
 
 .Lsyscall:
@@ -319,6 +321,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	ld	r10,TI_FLAGS(r10)
 
 	cmpldi	r0,NR_syscalls
+	barrier_nospec
 	blt+	.Lsyscall
 
 	/* Return code is already in r3 thanks to do_syscall_trace_enter() */
-- 
2.13.6