diff mbox series

[stable,4.14,v2,12/23] powerpc/powernv: Set or clear security feature flags

Message ID 20180526042749.5324-13-mpe@ellerman.id.au (mailing list archive)
State Not Applicable
Headers show
Series powerpc backports for 4.14 | expand

Commit Message

Michael Ellerman May 26, 2018, 4:27 a.m. UTC
commit 77addf6e95c8689e478d607176b399a6242a777e upstream.

Now that we have feature flags for security related things, set or
clear them based on what we see in the device tree provided by
firmware.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/powernv/setup.c | 56 ++++++++++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)
diff mbox series

Patch

diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 37a7f5ef00b7..4b7f2c00f870 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -37,9 +37,63 @@ 
 #include <asm/kexec.h>
 #include <asm/smp.h>
 #include <asm/setup.h>
+#include <asm/security_features.h>
 
 #include "powernv.h"
 
+
+static bool fw_feature_is(const char *state, const char *name,
+			  struct device_node *fw_features)
+{
+	struct device_node *np;
+	bool rc = false;
+
+	np = of_get_child_by_name(fw_features, name);
+	if (np) {
+		rc = of_property_read_bool(np, state);
+		of_node_put(np);
+	}
+
+	return rc;
+}
+
+static void init_fw_feat_flags(struct device_node *np)
+{
+	if (fw_feature_is("enabled", "inst-spec-barrier-ori31,31,0", np))
+		security_ftr_set(SEC_FTR_SPEC_BAR_ORI31);
+
+	if (fw_feature_is("enabled", "fw-bcctrl-serialized", np))
+		security_ftr_set(SEC_FTR_BCCTRL_SERIALISED);
+
+	if (fw_feature_is("enabled", "inst-spec-barrier-ori31,31,0", np))
+		security_ftr_set(SEC_FTR_L1D_FLUSH_ORI30);
+
+	if (fw_feature_is("enabled", "inst-l1d-flush-trig2", np))
+		security_ftr_set(SEC_FTR_L1D_FLUSH_TRIG2);
+
+	if (fw_feature_is("enabled", "fw-l1d-thread-split", np))
+		security_ftr_set(SEC_FTR_L1D_THREAD_PRIV);
+
+	if (fw_feature_is("enabled", "fw-count-cache-disabled", np))
+		security_ftr_set(SEC_FTR_COUNT_CACHE_DISABLED);
+
+	/*
+	 * The features below are enabled by default, so we instead look to see
+	 * if firmware has *disabled* them, and clear them if so.
+	 */
+	if (fw_feature_is("disabled", "speculation-policy-favor-security", np))
+		security_ftr_clear(SEC_FTR_FAVOUR_SECURITY);
+
+	if (fw_feature_is("disabled", "needs-l1d-flush-msr-pr-0-to-1", np))
+		security_ftr_clear(SEC_FTR_L1D_FLUSH_PR);
+
+	if (fw_feature_is("disabled", "needs-l1d-flush-msr-hv-1-to-0", np))
+		security_ftr_clear(SEC_FTR_L1D_FLUSH_HV);
+
+	if (fw_feature_is("disabled", "needs-spec-barrier-for-bound-checks", np))
+		security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR);
+}
+
 static void pnv_setup_rfi_flush(void)
 {
 	struct device_node *np, *fw_features;
@@ -55,6 +109,8 @@  static void pnv_setup_rfi_flush(void)
 	of_node_put(np);
 
 	if (fw_features) {
+		init_fw_feat_flags(fw_features);
+
 		np = of_get_child_by_name(fw_features, "inst-l1d-flush-trig2");
 		if (np && of_property_read_bool(np, "enabled"))
 			type = L1D_FLUSH_MTTRIG;