From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F16D1C369CB for ; Tue, 22 Apr 2025 07:06:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:MIME-Version:Message-ID:In-Reply-To:Date:From:Cc:To:Subject: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:References:List-Owner; bh=OQKcxxbp8U5jlZe9prXW+9Sc1apzVLwtQ5EJCrkq+ks=; b=xhRtVbkHSjJcmvYqZo83xkO1GZ O/pRoQ7CvxsfSv+ZlwX756a+2WkR3jOHW+4JHeEtbOCEpOHjNkYYyEKemV3dsSrf7PjKCQ2jWNU2A mP84TJ3l6LqBMu35MWntE/IL3cl7HvdH6SfdVA2Ju1sfRNC+iLpr1Y9EDK0cwBCa+GGzrkOm6s8Ln 26NhNmgUY1RzsMvEzDtF813JvOw8H+GKtGtIDa3MLguCWTGFLvy8QLyJX4qR+tPXo7okvbzKL7eTM W2tMbS5ZHy8EdkNmriOqAjy5V8plqJSGFDM8PWLnSqHmfz2qPj3vdDQeZLniCkIHWRc95C6fMhzVR vEVDZcCA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1u77hh-0000000647q-2mVW; Tue, 22 Apr 2025 07:06:01 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1u77Mt-000000061En-1JbC for linux-arm-kernel@lists.infradead.org; Tue, 22 Apr 2025 06:44:32 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 82D484A559; Tue, 22 Apr 2025 06:44:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 84E51C4CEEA; Tue, 22 Apr 2025 06:44:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745304270; bh=dB+6dmUg0IXUNTerGBybHiDJiTO7E/dRuC4+MPrUZOQ=; h=Subject:To:Cc:From:Date:In-Reply-To:From; b=JCNQO+YjihuiJTC9Qi8SFQLZmzCLGyVO4AWvhKR7YDsygJD5pV6cVTKZTF6y6noDp ay9WG/EwUZuklZs7pJ8DgQgAScO9TWXGJvYLcTeTOL9v35ZAE2MffztHlA0HOgTDdt 0GiGwzb6s0RQIsEZu9yV7CHNF6lRiuwepHZp6emU= Subject: Patch "KVM: arm64: Remove VHE host restore of CPACR_EL1.ZEN" has been added to the 6.1-stable tree To: broonie@kernel.org,catalin.marinas@arm.com,gregkh@linuxfoundation.org,james.morse@arm.com,kvmarm@lists.cs.columbia.edu,kvmarm@lists.linux.dev,linux-arm-kernel@lists.infradead.org,mark.rutland@arm.com,maz@kernel.org,oleg@redhat.com,oliver.upton@linux.dev,suzuki.poulose@arm.com,tabba@google.com,will@kernel.org Cc: From: Date: Tue, 22 Apr 2025 08:43:55 +0200 In-Reply-To: <20250404-stable-sve-6-1-v1-7-cd5c9eb52d49@kernel.org> Message-ID: <2025042255-substance-lumpish-e8d6@gregkh> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit X-stable: commit X-Patchwork-Hint: ignore X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250421_234431_397764_25B16825 X-CRM114-Status: GOOD ( 20.70 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org This is a note to let you know that I've just added the patch titled KVM: arm64: Remove VHE host restore of CPACR_EL1.ZEN to the 6.1-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: kvm-arm64-remove-vhe-host-restore-of-cpacr_el1.zen.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >From broonie@kernel.org Fri Apr 4 15:27:52 2025 From: Mark Brown Date: Fri, 04 Apr 2025 14:23:40 +0100 Subject: KVM: arm64: Remove VHE host restore of CPACR_EL1.ZEN To: Catalin Marinas , Will Deacon , Marc Zyngier , James Morse , Suzuki K Poulose , Oliver Upton , Oleg Nesterov , Greg Kroah-Hartman Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kvmarm@lists.linux.dev, kvmarm@lists.cs.columbia.edu, Mark Brown , stable@vger.kernel.org, Mark Rutland , Fuad Tabba Message-ID: <20250404-stable-sve-6-1-v1-7-cd5c9eb52d49@kernel.org> From: Mark Rutland [ Upstream commit 459f059be702056d91537b99a129994aa6ccdd35 ] When KVM is in VHE mode, the host kernel tries to save and restore the configuration of CPACR_EL1.ZEN (i.e. CPTR_EL2.ZEN when HCR_EL2.E2H=1) across kvm_arch_vcpu_load_fp() and kvm_arch_vcpu_put_fp(), since the configuration may be clobbered by hyp when running a vCPU. This logic is currently redundant. The VHE hyp code unconditionally configures CPTR_EL2.ZEN to 0b01 when returning to the host, permitting host kernel usage of SVE. Now that the host eagerly saves and unbinds its own FPSIMD/SVE/SME state, there's no need to save/restore the state of the EL0 SVE trap. The kernel can safely save/restore state without trapping, as described above, and will restore userspace state (including trap controls) before returning to userspace. Remove the redundant logic. Signed-off-by: Mark Rutland Reviewed-by: Mark Brown Tested-by: Mark Brown Acked-by: Will Deacon Cc: Catalin Marinas Cc: Fuad Tabba Cc: Marc Zyngier Cc: Oliver Upton Reviewed-by: Oliver Upton Link: https://lore.kernel.org/r/20250210195226.1215254-4-mark.rutland@arm.com Signed-off-by: Marc Zyngier [Rework for refactoring of where the flags are stored -- broonie] Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- arch/arm64/include/asm/kvm_host.h | 2 -- arch/arm64/kvm/fpsimd.c | 16 ---------------- 2 files changed, 18 deletions(-) --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -556,8 +556,6 @@ struct kvm_vcpu_arch { /* Save TRBE context if active */ #define DEBUG_STATE_SAVE_TRBE __vcpu_single_flag(iflags, BIT(6)) -/* SVE enabled for host EL0 */ -#define HOST_SVE_ENABLED __vcpu_single_flag(sflags, BIT(0)) /* SME enabled for EL0 */ #define HOST_SME_ENABLED __vcpu_single_flag(sflags, BIT(1)) /* Physical CPU not in supported_cpus */ --- a/arch/arm64/kvm/fpsimd.c +++ b/arch/arm64/kvm/fpsimd.c @@ -88,10 +88,6 @@ void kvm_arch_vcpu_load_fp(struct kvm_vc fpsimd_save_and_flush_cpu_state(); vcpu->arch.fp_state = FP_STATE_FREE; - vcpu_clear_flag(vcpu, HOST_SVE_ENABLED); - if (read_sysreg(cpacr_el1) & CPACR_EL1_ZEN_EL0EN) - vcpu_set_flag(vcpu, HOST_SVE_ENABLED); - /* * We don't currently support SME guests but if we leave * things in streaming mode then when the guest starts running @@ -193,18 +189,6 @@ void kvm_arch_vcpu_put_fp(struct kvm_vcp } fpsimd_save_and_flush_cpu_state(); - } else if (has_vhe() && system_supports_sve()) { - /* - * The FPSIMD/SVE state in the CPU has not been touched, and we - * have SVE (and VHE): CPACR_EL1 (alias CPTR_EL2) has been - * reset to CPACR_EL1_DEFAULT by the Hyp code, disabling SVE - * for EL0. To avoid spurious traps, restore the trap state - * seen by kvm_arch_vcpu_load_fp(): - */ - if (vcpu_get_flag(vcpu, HOST_SVE_ENABLED)) - sysreg_clear_set(CPACR_EL1, 0, CPACR_EL1_ZEN_EL0EN); - else - sysreg_clear_set(CPACR_EL1, CPACR_EL1_ZEN_EL0EN, 0); } local_irq_restore(flags); Patches currently in stable-queue which might be from broonie@kernel.org are queue-6.1/kvm-arm64-remove-host-fpsimd-saving-for-non-protected-kvm.patch queue-6.1/spi-cadence-qspi-fix-probe-on-am62a-lp-sk.patch queue-6.1/asoc-qdsp6-q6asm-dai-fix-q6asm_dai_compr_set_params-error-path.patch queue-6.1/asoc-qdsp6-q6apm-dai-fix-capture-pipeline-overruns.patch queue-6.1/kvm-arm64-mark-some-header-functions-as-inline.patch queue-6.1/kvm-arm64-eagerly-switch-zcr_el-1-2.patch queue-6.1/kvm-arm64-unconditionally-save-flush-host-fpsimd-sve-sme-state.patch queue-6.1/asoc-amd-add-dmi-quirk-for-acp6x-mic-support.patch queue-6.1/kvm-arm64-refactor-exit-handlers.patch queue-6.1/asoc-qdsp6-q6apm-dai-set-10-ms-period-and-buffer-alignment.patch queue-6.1/asoc-codecs-lpass-wsa-macro-fix-vi-feedback-rate.patch queue-6.1/arm64-fpsimd-track-the-saved-fpsimd-state-type-separately-to-tif_sve.patch queue-6.1/kvm-arm64-remove-vhe-host-restore-of-cpacr_el1.zen.patch queue-6.1/kvm-arm64-remove-vhe-host-restore-of-cpacr_el1.smen.patch queue-6.1/asoc-fsl_audmix-register-card-device-depends-on-dais.patch queue-6.1/arm64-fpsimd-have-kvm-explicitly-say-which-fp-registers-to-save.patch queue-6.1/kvm-arm64-discard-any-sve-state-when-entering-kvm-guests.patch queue-6.1/arm64-fpsimd-stop-using-tif_sve-to-manage-register-saving-in-kvm.patch queue-6.1/asoc-codecs-lpass-wsa-macro-fix-logic-of-enabling-vi-channels.patch queue-6.1/kvm-arm64-calculate-cptr_el2-traps-on-activating-traps.patch