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 98990C35FFC for ; Tue, 25 Mar 2025 11:37:41 +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=Rpnai9VXBrf/fJ/k4amxW5E+ReIs+XgkD+X/EeNU7Fc=; b=k0bxGyawYzolMt9CMCv1W6mjRS zQf+stF69ygNhClbPLxY67WRWcxtqiXND6Zi8WEeuyt0EnqRCtxamtIX/9LaU34TNj3t9r0znlBSV hcbLuVKMMd9qeVUxR8YzO3o83JByssU7fcQFR53SSJRdk1wY1gnOW9v0rZ4/HeoVcOrbab/b63ZWl oPIiX/fkTejUQ0Q0qGO/jo4V2/Q6CbTjBbxAUG9CU2xAfflVlBKfyRfbCEKESQKEwhpb0HNxV3UUg bP9OJDU4JqQIkKqDLHIYOAtXHOpLXbSw7xihAGN1MRVxQaEphiqQFgvDPSNtVAUDfa8cyaM0JJlio iWtWs+zA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1tx2ax-00000005ens-1DQS; Tue, 25 Mar 2025 11:37:23 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.98.1 #2 (Red Hat Linux)) id 1tx2UJ-00000005dis-2ZWy for linux-arm-kernel@lists.infradead.org; Tue, 25 Mar 2025 11:30:33 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id EADC85C57EB; Tue, 25 Mar 2025 11:28:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6D36CC4CEE4; Tue, 25 Mar 2025 11:30:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1742902230; bh=bW5pq7nRDARYHxsUJPciapbMKvnHI6897yo2Pn8WucE=; h=Subject:To:Cc:From:Date:In-Reply-To:From; b=RhYxyk2Vhd8slEi/vkRdp1buodTxIbMqG+g1M/SxXRtQ99e4SRTtS3jDg/HFmpmAh SbQlYlXk008V/oKUQ98p/tAcgtxakEEwlLf02hMvTrS+WvATN1sQgFAQjjUxND5+qU BPeQ8WzQOngIoE9YjcXaSWpugE+8wvPBSifC7Ayk= Subject: Patch "KVM: arm64: Remove host FPSIMD saving for non-protected KVM" has been added to the 6.6-stable tree To: broonie@kernel.org,catalin.marinas@arm.com,gregkh@linuxfoundation.org,james.morse@arm.com,kvmarm@lists.linux.dev,linux-arm-kernel@lists.infradead.org,mark.rutland@arm.com,maz@kernel.org,oliver.upton@linux.dev,suzuki.poulose@arm.com,tabba@google.com,will@kernel.org Cc: From: Date: Tue, 25 Mar 2025 07:28:56 -0400 In-Reply-To: <20250321-stable-sve-6-6-v1-3-0b3a6a14ea53@kernel.org> Message-ID: <2025032556-quizzical-epilogue-bf3b@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-20250325_043031_770226_BFC59BD1 X-CRM114-Status: GOOD ( 21.07 ) 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 host FPSIMD saving for non-protected KVM to the 6.6-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-host-fpsimd-saving-for-non-protected-kvm.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >From stable+bounces-125721-greg=kroah.com@vger.kernel.org Thu Mar 20 20:20:22 2025 From: Mark Brown Date: Fri, 21 Mar 2025 00:16:03 +0000 Subject: KVM: arm64: Remove host FPSIMD saving for non-protected KVM To: Greg Kroah-Hartman , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Catalin Marinas , Will Deacon Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Mark Brown , Mark Rutland , Fuad Tabba Message-ID: <20250321-stable-sve-6-6-v1-3-0b3a6a14ea53@kernel.org> From: Mark Rutland [ Upstream commit 8eca7f6d5100b6997df4f532090bc3f7e0203bef ] Now that the host eagerly saves its own FPSIMD/SVE/SME state, non-protected KVM never needs to save the host FPSIMD/SVE/SME state, and the code to do this is never used. Protected KVM still needs to save/restore the host FPSIMD/SVE state to avoid leaking guest state to the host (and to avoid revealing to the host whether the guest used FPSIMD/SVE/SME), and that code needs to be retained. Remove the unused code and data structures. To avoid the need for a stub copy of kvm_hyp_save_fpsimd_host() in the VHE hyp code, the nVHE/hVHE version is moved into the shared switch header, where it is only invoked when KVM is in protected mode. 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/20250210195226.1215254-3-mark.rutland@arm.com Signed-off-by: Marc Zyngier Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- arch/arm64/include/asm/kvm_host.h | 1 - arch/arm64/kvm/fpsimd.c | 2 -- arch/arm64/kvm/hyp/include/hyp/switch.h | 4 ---- arch/arm64/kvm/hyp/nvhe/hyp-main.c | 1 - 4 files changed, 8 deletions(-) --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -535,7 +535,6 @@ struct kvm_vcpu_arch { struct kvm_guest_debug_arch vcpu_debug_state; struct kvm_guest_debug_arch external_debug_state; - struct user_fpsimd_state *host_fpsimd_state; /* hyp VA */ struct task_struct *parent_task; struct { --- a/arch/arm64/kvm/fpsimd.c +++ b/arch/arm64/kvm/fpsimd.c @@ -49,8 +49,6 @@ int kvm_arch_vcpu_run_map_fp(struct kvm_ if (ret) return ret; - vcpu->arch.host_fpsimd_state = kern_hyp_va(fpsimd); - /* * We need to keep current's task_struct pinned until its data has been * unshared with the hypervisor to make sure it is not re-used by the --- a/arch/arm64/kvm/hyp/include/hyp/switch.h +++ b/arch/arm64/kvm/hyp/include/hyp/switch.h @@ -321,10 +321,6 @@ static bool kvm_hyp_handle_fpsimd(struct } isb(); - /* Write out the host state if it's in the registers */ - if (vcpu->arch.fp_state == FP_STATE_HOST_OWNED) - __fpsimd_save_state(vcpu->arch.host_fpsimd_state); - /* Restore the guest state */ if (sve_guest) __hyp_sve_restore_guest(vcpu); --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -41,7 +41,6 @@ static void flush_hyp_vcpu(struct pkvm_h hyp_vcpu->vcpu.arch.fp_state = host_vcpu->arch.fp_state; hyp_vcpu->vcpu.arch.debug_ptr = kern_hyp_va(host_vcpu->arch.debug_ptr); - hyp_vcpu->vcpu.arch.host_fpsimd_state = host_vcpu->arch.host_fpsimd_state; hyp_vcpu->vcpu.arch.vsesr_el2 = host_vcpu->arch.vsesr_el2; Patches currently in stable-queue which might be from broonie@kernel.org are queue-6.6/kvm-arm64-calculate-cptr_el2-traps-on-activating-traps.patch queue-6.6/regulator-check-that-dummy-regulator-has-been-probed-before-using-it.patch queue-6.6/kvm-arm64-eagerly-switch-zcr_el-1-2.patch queue-6.6/kvm-arm64-mark-some-header-functions-as-inline.patch queue-6.6/kvm-arm64-remove-host-fpsimd-saving-for-non-protected-kvm.patch queue-6.6/regulator-dummy-force-synchronous-probing.patch queue-6.6/kvm-arm64-refactor-exit-handlers.patch queue-6.6/kvm-arm64-unconditionally-save-flush-host-fpsimd-sve-sme-state.patch queue-6.6/kvm-arm64-remove-vhe-host-restore-of-cpacr_el1.smen.patch queue-6.6/kvm-arm64-remove-vhe-host-restore-of-cpacr_el1.zen.patch