From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:43762 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965239AbeBMQdY (ORCPT ); Tue, 13 Feb 2018 11:33:24 -0500 Subject: Patch "[Variant 2/Spectre-v2] arm64: KVM: Make PSCI_VERSION a fast path" has been added to the 4.15-stable tree To: marc.zyngier@arm.com, catalin.marinas@arm.com, gregkh@linuxfoundation.org, will.deacon@arm.com Cc: , From: Date: Tue, 13 Feb 2018 17:31:42 +0100 Message-ID: <151853950299110@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled [Variant 2/Spectre-v2] arm64: KVM: Make PSCI_VERSION a fast path 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: arm64-kvm-make-psci_version-a-fast-path.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 know about it. >>From foo@baz Tue Feb 13 17:25:10 CET 2018 From: Marc Zyngier Date: Wed, 3 Jan 2018 16:38:37 +0000 Subject: [Variant 2/Spectre-v2] arm64: KVM: Make PSCI_VERSION a fast path From: Marc Zyngier Commit 90348689d500 upstream. For those CPUs that require PSCI to perform a BP invalidation, going all the way to the PSCI code for not much is a waste of precious cycles. Let's terminate that call as early as possible. Signed-off-by: Marc Zyngier Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kvm/hyp/switch.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -17,6 +17,7 @@ #include #include +#include #include #include @@ -341,6 +342,18 @@ again: if (exit_code == ARM_EXCEPTION_TRAP && !__populate_fault_info(vcpu)) goto 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; + + vcpu_set_reg(vcpu, 0, val); + goto again; + } + if (static_branch_unlikely(&vgic_v2_cpuif_trap) && exit_code == ARM_EXCEPTION_TRAP) { bool valid; Patches currently in stable-queue which might be from marc.zyngier@arm.com 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