[PATCH 4.9 25/61] powerpc/pseries: Support firmware disable of RFI flush

From: Greg Kroah-Hartman
Date: Tue Jun 05 2018 - 13:11:02 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Michael Ellerman <mpe@xxxxxxxxxxxxxx>

commit 582605a429e20ae68fd0b041b2e840af296edd08 upstream.

Some versions of firmware will have a setting that can be configured
to disable the RFI flush, add support for it.

Fixes: 8989d56878a7 ("powerpc/pseries: Query hypervisor for RFI flush settings")
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/powerpc/platforms/pseries/setup.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -473,7 +473,8 @@ static void pseries_setup_rfi_flush(void
if (types == L1D_FLUSH_NONE)
types = L1D_FLUSH_FALLBACK;

- if (!(result.behaviour & H_CPU_BEHAV_L1D_FLUSH_PR))
+ if ((!(result.behaviour & H_CPU_BEHAV_L1D_FLUSH_PR)) ||
+ (!(result.behaviour & H_CPU_BEHAV_FAVOUR_SECURITY)))
enable = false;
} else {
/* Default to fallback if case hcall is not available */