From 4d877002df95d0d4f47f5cc19f560c5509f97fa9 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Mon, 8 Jan 2018 21:40:57 +0530 Subject: [PATCH 04/26] UBUNTU: SAUCE: rfi-flush: Fallback flush add load dependency CVE-2017-5754 Add a data dependency on loads for the fallback flush. This reduces or eliminates instances of incomplete flushing on P8 and P9. Signed-off-by: Nicholas Piggin Signed-off-by: Stefan Bader --- arch/powerpc/kernel/exceptions-64s.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 3b73dbb..5271bee 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -681,8 +681,8 @@ rfi_flush_fallback: .rept 8 /* 8-way set associative */ ldx r11,r10,r8 add r8,r8,r12 + add r8,r8,r11 /* r11 will be 0, but this creates a dependency */ .endr - lwsync /* Ensure that we do all 8 sets before others */ addi r10,r10,128 /* 128 byte cache line */ bdnz 1b @@ -723,8 +723,8 @@ hrfi_flush_fallback: .rept 8 /* 8-way set associative */ ldx r11,r10,r8 add r8,r8,r12 + add r8,r8,r11 /* r11 will be 0, but this creates a dependency */ .endr - lwsync /* Ensure that we do all 8 sets before others */ addi r10,r10,128 /* 128 byte cache line */ bdnz 1b -- 2.7.4