Hook up an override for GCS, allowing it to be disabled from the command
line by specifying arm64.nogcs in case there are problems.
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
Documentation/admin-guide/kernel-parameters.txt | 6 ++++++
arch/arm64/kernel/idreg-override.c | 2 ++
2 files changed, 8 insertions(+)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 31b3a25680d0..e86160251d23 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -429,9 +429,15 @@
arm64.nobti [ARM64] Unconditionally disable Branch Target
Identification support
+ arm64.nogcs [ARM64] Unconditionally disable Guarded Control Stack
+ support
+
arm64.nomops [ARM64] Unconditionally disable Memory Copy and Memory
Set instructions support
+ arm64.nopauth [ARM64] Unconditionally disable Pointer Authentication
+ support
+
arm64.nomte [ARM64] Unconditionally disable Memory Tagging Extension
support
diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c
index e30fd9e32ef3..00bcdad53ba9 100644
--- a/arch/arm64/kernel/idreg-override.c
+++ b/arch/arm64/kernel/idreg-override.c
@@ -110,6 +110,7 @@ static const struct ftr_set_desc pfr1 __prel64_initconst = {
.override = &id_aa64pfr1_override,
.fields = {
FIELD("bt", ID_AA64PFR1_EL1_BT_SHIFT, NULL ),
+ FIELD("gcs", ID_AA64PFR1_EL1_GCS_SHIFT, NULL),
FIELD("mte", ID_AA64PFR1_EL1_MTE_SHIFT, NULL),
FIELD("sme", ID_AA64PFR1_EL1_SME_SHIFT, pfr1_sme_filter),
{}
@@ -190,6 +191,7 @@ static const struct {
{ "arm64.nosve", "id_aa64pfr0.sve=0" },
{ "arm64.nosme", "id_aa64pfr1.sme=0" },
{ "arm64.nobti", "id_aa64pfr1.bt=0" },
+ { "arm64.nogcs", "id_aa64pfr1.gcs=0" },
{ "arm64.nopauth",
"id_aa64isar1.gpi=0 id_aa64isar1.gpa=0 "
"id_aa64isar1.api=0 id_aa64isar1.apa=0 "
--
2.30.2
