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 733D2C369C2 for ; Tue, 22 Apr 2025 07:25:14 +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=i4lzJOVmubU4qEM22UJOgcZQQvLqy6KDiuV5MdDSBjM=; b=H7XYBo2jkAOGlw8B/yTqqe882l atL0et6XxFofXQ4Duu57/xfIaNWEUgG58w4MqmPryT1hv2lFaKwA2s9z2Whoa7WsBOS4SEuPTSB0J NqI2vrFUGihtZEMTLYKh4Vb/Eo4fDfiF6pxIlectMMXuxd+AgOlz6FqBOneU4EYVxUdIj7FDc0yoJ CnAJb6KwjSN+22vkQWCTrZhzSlHCmVacV/cGVeKpzY+b94BUDoMOdPaBKBjrCPEc/mak6R5GblJmY 4+FhsxWTuScP3gTIUXMCGhJ2h+L6G8xl4fP6Xu2BCu+4ZzwFbIt9Q08srU3o+vjM8Hx1WQBn0WYqr bg/1Es/w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1u7808-000000066kS-1Hwv; Tue, 22 Apr 2025 07:25:04 +0000 Received: from nyc.source.kernel.org ([147.75.193.91]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1u77O3-000000061W2-3MFD for linux-arm-kernel@lists.infradead.org; Tue, 22 Apr 2025 06:45:45 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id F3171A4BB80; Tue, 22 Apr 2025 06:40:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 736CCC4CEE9; Tue, 22 Apr 2025 06:45:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745304342; bh=dIw58j1gVcougg+hZPtMrESPWfcdq4Qzac/zdEIkZrI=; h=Subject:To:Cc:From:Date:In-Reply-To:From; b=Q/B5Z2lETCuv+Uuxz/GZyifRbkS3KcfmbnoJgokgOwOwFsWiTzfVqxVEDUDDzQYLr y9a4nMp8M8Rdnv/7EoRv6vz3NXIkx9LxL25UG+UI8iFqndZtKJwSuqX6NTyROHplr+ TR7kyjsmU73GWTUHZVcHelH7ZxtGX55vDwYKHP5M= Subject: Patch "KVM: arm64: Remove VHE host restore of CPACR_EL1.ZEN" has been added to the 5.15-stable tree To: broonie@kernel.org,catalin.marinas@arm.com,gregkh@linuxfoundation.org,james.morse@arm.com,kvmarm@lists.cs.columbia.edu,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 08:45:14 +0200 In-Reply-To: <20250408-stable-sve-5-15-v3-9-ca9a6b850f55@kernel.org> Message-ID: <2025042214-napped-revocable-512f@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_234543_974455_7C3835B1 X-CRM114-Status: GOOD ( 19.58 ) 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 5.15-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: kvm-arm64-remove-vhe-host-restore-of-cpacr_el1.zen.patch and it can be found in the queue-5.15 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 Tue Apr 8 20:22:47 2025 From: Mark Brown Date: Tue, 08 Apr 2025 19:10:04 +0100 Subject: KVM: arm64: Remove VHE host restore of CPACR_EL1.ZEN To: Greg Kroah-Hartman , Marc Zyngier , James Morse , Suzuki K Poulose , Catalin Marinas , Will Deacon , Oleg Nesterov , Oliver Upton Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Mark Brown , Mark Rutland , Fuad Tabba Message-ID: <20250408-stable-sve-5-15-v3-9-ca9a6b850f55@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 | 1 - arch/arm64/kvm/fpsimd.c | 15 --------------- 2 files changed, 16 deletions(-) --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -421,7 +421,6 @@ struct kvm_vcpu_arch { #define KVM_ARM64_DEBUG_DIRTY (1 << 0) #define KVM_ARM64_FP_ENABLED (1 << 1) /* guest FP regs loaded */ #define KVM_ARM64_FP_HOST (1 << 2) /* host FP regs loaded */ -#define KVM_ARM64_HOST_SVE_ENABLED (1 << 4) /* SVE enabled for EL0 */ #define KVM_ARM64_GUEST_HAS_SVE (1 << 5) /* SVE exposed to guest */ #define KVM_ARM64_VCPU_SVE_FINALIZED (1 << 6) /* SVE config completed */ #define KVM_ARM64_GUEST_HAS_PTRAUTH (1 << 7) /* PTRAUTH exposed to guest */ --- a/arch/arm64/kvm/fpsimd.c +++ b/arch/arm64/kvm/fpsimd.c @@ -83,9 +83,6 @@ void kvm_arch_vcpu_load_fp(struct kvm_vc */ fpsimd_save_and_flush_cpu_state(); vcpu->arch.flags &= ~KVM_ARM64_FP_HOST; - - if (read_sysreg(cpacr_el1) & CPACR_EL1_ZEN_EL0EN) - vcpu->arch.flags |= KVM_ARM64_HOST_SVE_ENABLED; } /* @@ -142,18 +139,6 @@ 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->arch.flags & KVM_ARM64_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-5.15/kvm-arm64-remove-host-fpsimd-saving-for-non-protected-kvm.patch queue-5.15/spi-cadence-qspi-fix-probe-on-am62a-lp-sk.patch queue-5.15/asoc-qdsp6-q6asm-dai-fix-q6asm_dai_compr_set_params-error-path.patch queue-5.15/kvm-arm64-eagerly-switch-zcr_el-1-2.patch queue-5.15/kvm-arm64-unconditionally-save-flush-host-fpsimd-sve-sme-state.patch queue-5.15/kvm-arm64-always-start-with-clearing-sve-flag-on-load.patch queue-5.15/asoc-codecs-lpass-wsa-macro-fix-vi-feedback-rate.patch queue-5.15/arm64-fpsimd-track-the-saved-fpsimd-state-type-separately-to-tif_sve.patch queue-5.15/kvm-arm64-get-rid-of-host-sve-tracking-saving.patch queue-5.15/kvm-arm64-remove-vhe-host-restore-of-cpacr_el1.zen.patch queue-5.15/asoc-fsl_audmix-register-card-device-depends-on-dais.patch queue-5.15/arm64-fpsimd-have-kvm-explicitly-say-which-fp-registers-to-save.patch queue-5.15/kvm-arm64-discard-any-sve-state-when-entering-kvm-guests.patch queue-5.15/arm64-fpsimd-stop-using-tif_sve-to-manage-register-saving-in-kvm.patch queue-5.15/asoc-codecs-lpass-wsa-macro-fix-logic-of-enabling-vi-channels.patch queue-5.15/kvm-arm64-calculate-cptr_el2-traps-on-activating-traps.patch