This is a note to let you know that I've just added the patch titled
powerpc/powernv: Set or clear security feature flags
to the 4.16-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
powerpc-powernv-set-or-clear-security-feature-flags.patch
and it can be found in the queue-4.16 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <sta...@vger.kernel.org> know about it.
>From foo@baz Wed May 23 19:18:22 CEST 2018
From: Michael Ellerman <m...@ellerman.id.au>
Date: Wed, 23 May 2018 00:41:16 +1000
Subject: powerpc/powernv: Set or clear security feature flags
To: g...@kroah.com
Cc: sta...@vger.kernel.org, t...@linutronix.de, linuxppc-...@ozlabs.org
Message-ID: <20180522144125.10345-6-...@ellerman.id.au>
From: Michael Ellerman <m...@ellerman.id.au>
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 <m...@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
arch/powerpc/platforms/powernv/setup.c | 56 +++++++++++++++++++++++++++++++++
1 file changed, 56 insertions(+)
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -38,9 +38,63 @@
#include <asm/smp.h>
#include <asm/tm.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;
@@ -56,6 +110,8 @@ 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;
Patches currently in stable-queue which might be from m...@ellerman.id.au are
queue-4.16/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.16/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.16/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.16/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.16/powerpc-move-default-security-feature-flags.patch
queue-4.16/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.16/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.16/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.16/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.16/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.16/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.16/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.16/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.16/powerpc-64s-wire-up-cpu_show_spectre_v2.patch
