[PATCH 2/2] KVM: doc: add API documentation on the KVM_REG_ARM_WORKAROUNDS register

[Andre Przywara <andre.przywara@arm.com>]

Add documentation for the newly defined firmware registers to save and
restore any vulnerability migitation status.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
---
 Documentation/virtual/kvm/arm/psci.txt | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/Documentation/virtual/kvm/arm/psci.txt b/Documentation/virtual/kvm/arm/psci.txt
index aafdab887b04..1270dc22acac 100644
--- a/Documentation/virtual/kvm/arm/psci.txt
+++ b/Documentation/virtual/kvm/arm/psci.txt
@@ -28,3 +28,23 @@ The following register is defined:
   - Allows any PSCI version implemented by KVM and compatible with
     v0.2 to be set with SET_ONE_REG
   - Affects the whole VM (even if the register view is per-vcpu)
+
+* KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1:
+  Holds the state of the firmware controlled workaround to mitigate
+  CVE-2017-5715, as described under SMCCC_ARCH_WORKAROUND_1 in [1].
+  Accepted values are:
+    KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL: Workaround not available.
+    KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_AVAIL: Workaround active for the guest.
+
+* KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2:
+  Holds the state of the firmware controlled workaround to mitigate
+  CVE-2018-3639, as described under SMCCC_ARCH_WORKAROUND_2 in [1].
+  Accepted values are:
+    KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL: Workaround not available.
+    KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL: Workaround available, and can
+      be disabled by a vCPU. If KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED is
+      set, it is active for this vCPU.
+    KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_UNAFFECTED: Workaround always active
+      or not needed.
+
+[1] https://developer.arm.com/-/media/developer/pdf/ARM_DEN_0070A_Firmware_interfaces_for_mitigating_CVE-2017-5715.pdf
-- 
2.17.1