This is a note to let you know that I've just added the patch titled
[Variant 2/Spectre-v2] arm/arm64: KVM: Turn kvm_psci_version into a static inline
to the 4.15-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:
arm-arm64-kvm-turn-kvm_psci_version-into-a-static-inline.patch
and it can be found in the queue-4.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Tue Feb 13 17:25:10 CET 2018
From: Marc Zyngier <marc.zyngier@xxxxxxx>
Date: Tue, 6 Feb 2018 17:56:13 +0000
Subject: [Variant 2/Spectre-v2] arm/arm64: KVM: Turn kvm_psci_version into a static inline
From: Marc Zyngier <marc.zyngier@xxxxxxx>
Commit a4097b351118 upstream.
We're about to need kvm_psci_version in HYP too. So let's turn it
into a static inline, and pass the kvm structure as a second
parameter (so that HYP can do a kern_hyp_va on it).
Tested-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Reviewed-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx>
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/arm64/kvm/hyp/switch.c | 18 +++++++++++-------
include/kvm/arm_psci.h | 21 ++++++++++++++++++++-
virt/kvm/arm/psci.c | 12 ++----------
3 files changed, 33 insertions(+), 18 deletions(-)
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -19,6 +19,8 @@
#include <linux/jump_label.h>
#include <uapi/linux/psci.h>
+#include <kvm/arm_psci.h>
+
#include <asm/kvm_asm.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_hyp.h>
@@ -344,14 +346,16 @@ again:
if (exit_code == ARM_EXCEPTION_TRAP &&
(kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_HVC64 ||
- kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_HVC32) &&
- vcpu_get_reg(vcpu, 0) == PSCI_0_2_FN_PSCI_VERSION) {
- u64 val = PSCI_RET_NOT_SUPPORTED;
- if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
- val = 2;
+ kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_HVC32)) {
+ u32 val = vcpu_get_reg(vcpu, 0);
- vcpu_set_reg(vcpu, 0, val);
- goto again;
+ if (val == PSCI_0_2_FN_PSCI_VERSION) {
+ val = kvm_psci_version(vcpu, kern_hyp_va(vcpu->kvm));
+ if (unlikely(val == KVM_ARM_PSCI_0_1))
+ val = PSCI_RET_NOT_SUPPORTED;
+ vcpu_set_reg(vcpu, 0, val);
+ goto again;
+ }
}
if (static_branch_unlikely(&vgic_v2_cpuif_trap) &&
--- a/include/kvm/arm_psci.h
+++ b/include/kvm/arm_psci.h
@@ -18,6 +18,7 @@
#ifndef __KVM_ARM_PSCI_H__
#define __KVM_ARM_PSCI_H__
+#include <linux/kvm_host.h>
#include <uapi/linux/psci.h>
#define KVM_ARM_PSCI_0_1 PSCI_VERSION(0, 1)
@@ -26,7 +27,25 @@
#define KVM_ARM_PSCI_LATEST KVM_ARM_PSCI_1_0
-int kvm_psci_version(struct kvm_vcpu *vcpu);
+/*
+ * We need the KVM pointer independently from the vcpu as we can call
+ * this from HYP, and need to apply kern_hyp_va on it...
+ */
+static inline int kvm_psci_version(struct kvm_vcpu *vcpu, struct kvm *kvm)
+{
+ /*
+ * Our PSCI implementation stays the same across versions from
+ * v0.2 onward, only adding the few mandatory functions (such
+ * as FEATURES with 1.0) that are required by newer
+ * revisions. It is thus safe to return the latest.
+ */
+ if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
+ return KVM_ARM_PSCI_LATEST;
+
+ return KVM_ARM_PSCI_0_1;
+}
+
+
int kvm_hvc_call_handler(struct kvm_vcpu *vcpu);
#endif /* __KVM_ARM_PSCI_H__ */
--- a/virt/kvm/arm/psci.c
+++ b/virt/kvm/arm/psci.c
@@ -123,7 +123,7 @@ static unsigned long kvm_psci_vcpu_on(st
if (!vcpu)
return PSCI_RET_INVALID_PARAMS;
if (!vcpu->arch.power_off) {
- if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1)
+ if (kvm_psci_version(source_vcpu, kvm) != KVM_ARM_PSCI_0_1)
return PSCI_RET_ALREADY_ON;
else
return PSCI_RET_INVALID_PARAMS;
@@ -232,14 +232,6 @@ static void kvm_psci_system_reset(struct
kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_RESET);
}
-int kvm_psci_version(struct kvm_vcpu *vcpu)
-{
- if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
- return KVM_ARM_PSCI_LATEST;
-
- return KVM_ARM_PSCI_0_1;
-}
-
static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
{
struct kvm *kvm = vcpu->kvm;
@@ -397,7 +389,7 @@ static int kvm_psci_0_1_call(struct kvm_
*/
static int kvm_psci_call(struct kvm_vcpu *vcpu)
{
- switch (kvm_psci_version(vcpu)) {
+ switch (kvm_psci_version(vcpu, vcpu->kvm)) {
case KVM_ARM_PSCI_1_0:
return kvm_psci_1_0_call(vcpu);
case KVM_ARM_PSCI_0_2:
Patches currently in stable-queue which might be from marc.zyngier@xxxxxxx are
queue-4.15/arm-arm64-smccc-make-function-identifiers-an-unsigned-quantity.patch
queue-4.15/arm64-move-bp-hardening-to-check_and_switch_context.patch
queue-4.15/arm-arm64-kvm-advertise-smccc-v1.1.patch
queue-4.15/arm64-move-post_ttbr_update_workaround-to-c-code.patch
queue-4.15/firmware-psci-expose-psci-conduit.patch
queue-4.15/arm64-force-kpti-to-be-disabled-on-cavium-thunderx.patch
queue-4.15/arm64-entry-apply-bp-hardening-for-high-priority-synchronous-exceptions.patch
queue-4.15/arm64-kpti-fix-the-interaction-between-asid-switching-and-software-pan.patch
queue-4.15/firmware-psci-expose-smccc-version-through-psci_ops.patch
queue-4.15/arm64-implement-branch-predictor-hardening-for-affected-cortex-a-cpus.patch
queue-4.15/arm-arm64-kvm-add-psci_version-helper.patch
queue-4.15/arm64-kill-psci_get_version-as-a-variant-2-workaround.patch
queue-4.15/arm64-entry-apply-bp-hardening-for-suspicious-interrupts-from-el0.patch
queue-4.15/arm64-capabilities-handle-duplicate-entries-for-a-capability.patch
queue-4.15/arm64-add-arm_smccc_arch_workaround_1-bp-hardening-support.patch
queue-4.15/arm-arm64-kvm-turn-kvm_psci_version-into-a-static-inline.patch
queue-4.15/arm-arm64-kvm-implement-psci-1.0-support.patch
queue-4.15/arm64-kvm-add-smccc_arch_workaround_1-fast-handling.patch
queue-4.15/arm64-kvm-report-smccc_arch_workaround_1-bp-hardening-support.patch
queue-4.15/arm-arm64-smccc-implement-smccc-v1.1-inline-primitive.patch
queue-4.15/arm64-idmap-use-awx-flags-for-.idmap.text-.pushsection-directives.patch
queue-4.15/arm64-kvm-make-psci_version-a-fast-path.patch
queue-4.15/arm64-cpufeature-__this_cpu_has_cap-shouldn-t-stop-early.patch
queue-4.15/arm64-kpti-add-enable-callback-to-remap-swapper-using-ng-mappings.patch
queue-4.15/arm-arm64-kvm-consolidate-the-psci-include-files.patch
queue-4.15/arm64-add-skeleton-to-harden-the-branch-predictor-against-aliasing-attacks.patch
queue-4.15/arm-arm64-kvm-add-smccc-accessors-to-psci-code.patch
queue-4.15/arm64-kvm-use-per-cpu-vector-when-bp-hardening-is-enabled.patch
queue-4.15/arm64-kvm-increment-pc-after-handling-an-smc-trap.patch