[PATCH stable v4.9 32/35] powerpc/fsl: Update Spectre v2 reporting

Michael Ellerman
2019-04-11T11:47:25Z

From: Diana Craciun <diana.craciun@nxp.com>

commit dfa88658fb0583abb92e062c7a9cd5a5b94f2a46 upstream.

Report branch predictor state flush as a mitigation for
Spectre variant 2.

Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
arch/powerpc/kernel/security.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index 6dc5cdc2b87c..43ce800e73bf 100644
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -213,8 +213,11 @@ ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, c

if (count_cache_flush_type == COUNT_CACHE_FLUSH_HW)
seq_buf_printf(&s, "(hardware accelerated)");
- } else
+ } else if (btb_flush_enabled) {
+ seq_buf_printf(&s, "Mitigation: Branch predictor state flush");
+ } else {
seq_buf_printf(&s, "Vulnerable");
+ }

seq_buf_printf(&s, "\n");

--
2.20.1