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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8162FC433F5 for ; Tue, 10 May 2022 09:44:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239137AbiEJJsi (ORCPT ); Tue, 10 May 2022 05:48:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34828 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239132AbiEJJsg (ORCPT ); Tue, 10 May 2022 05:48:36 -0400 Received: from mail-oi1-x231.google.com (mail-oi1-x231.google.com [IPv6:2607:f8b0:4864:20::231]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6B2D829B81C for ; Tue, 10 May 2022 02:44:40 -0700 (PDT) Received: by mail-oi1-x231.google.com with SMTP id w130so6081937oig.0 for ; Tue, 10 May 2022 02:44:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=tYmmaSjEQ0DAQ3hg78JmoXw7IWzTfCf5R6XNgYIbQdw=; b=jCnsf3hK1Pir0MXvc5uMjsEDPJnUI43QrFH+brw/Jo2vC6JSYoNSPTUX2qfDOJZQvf HUWB+IHA3rcd9mhQPx6R/EXneddFLEbJeYWjrRiGFPrgVvQnLOSEC+Xmh5brb/vcOqYj SNj66hg7iLoRFudTYvCzNI3qm5tMvIQ5pgrEWeK38YkYHMDDuMT/6BSbHrqdVWO+2HJR TLF2DKCb/iU6Wt1bZBpEhNA71HvYwYqmNyFreQULZ3U362tk6ARL/I1Cw9kjbWWopUbC fusK9b2Q7CQuUuPMnQTUcnoszsTym+W4jqOu/GBwu4egVLuEheEp8Sdm8ERqeZgd/nio Tclg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=tYmmaSjEQ0DAQ3hg78JmoXw7IWzTfCf5R6XNgYIbQdw=; b=tXSTkUAM3Jcz54LEMkqbTQJ4vWLhaGLuaF9WBgeq3bj3ycrDb66JRsTrl3X0/B798/ tPQ4xdsKn3bdaFAnxiYoEbT8zkr1iYSuK04nXK5CBs7zl7Tcgo0T7VuaTigjRf5OQmeq FNCt/+wb3jfO+HQBC2Kari1PYzkMBcMpp1JviGd5MfrKAvSXmYeoPb0Y96Flu3Ze7Soe KdZmPsB5khaO/6GNkVA0jly3ygZz2drL/7zjt5iKVQA4F1kCq+FcxY4QXUSUJg6zSWOt WQ5Sv9r6IJVxg1ESDouimQIPI8hs+0rwMWogC7BTxTm1Wkzxc14OcwHNOx4rXimauiiK WLhQ== X-Gm-Message-State: AOAM533KisDLj4XCZVbNkz8y6rTOcdyHZVQ2GqOhzwdaz9WOKEzrKjx2 6Ke7HZ+Nf7t1+7/wpbuVFrheFjSk9aajcJe3yvfljQ== X-Google-Smtp-Source: ABdhPJwi2uvaLL5WnzUOVGJ8SKVlBEr9x64tGdRwKs5uPLqPlRBlIPuG/lgPmYNqeBIi9V5qKOAF0+eR3XEjjvTNyWo= X-Received: by 2002:aca:180b:0:b0:2f7:23ae:8cd1 with SMTP id h11-20020aca180b000000b002f723ae8cd1mr13432825oih.146.1652175878175; Tue, 10 May 2022 02:44:38 -0700 (PDT) MIME-Version: 1.0 References: <20220509162559.2387784-1-oupton@google.com> <20220509162559.2387784-2-oupton@google.com> In-Reply-To: <20220509162559.2387784-2-oupton@google.com> From: Fuad Tabba Date: Tue, 10 May 2022 10:44:01 +0100 Message-ID: Subject: Re: [PATCH 1/2] KVM: arm64: pkvm: Drop unnecessary FP/SIMD trap handler To: Oliver Upton Cc: kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, maz@kernel.org, james.morse@arm.com, alexandru.elisei@arm.com, suzuki.poulose@arm.com, qperret@google.com, will@kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Oliver, On Mon, May 9, 2022 at 5:26 PM Oliver Upton wrote: > > The pVM-specific FP/SIMD trap handler just calls straight into the > generic trap handler. Avoid the indirection and just call the hyp > handler directly. > > Note that the BUILD_BUG_ON() pattern is repeated in > pvm_init_traps_aa64pfr0(), which is likely a better home for it. > > No functional change intended. Reviewed-by: Fuad Tabba Cheers, /fuad > > Signed-off-by: Oliver Upton > --- > arch/arm64/kvm/hyp/nvhe/switch.c | 19 +------------------ > 1 file changed, 1 insertion(+), 18 deletions(-) > > diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c > index 6410d21d8695..3dee2ad96e10 100644 > --- a/arch/arm64/kvm/hyp/nvhe/switch.c > +++ b/arch/arm64/kvm/hyp/nvhe/switch.c > @@ -175,23 +175,6 @@ static bool kvm_handle_pvm_sys64(struct kvm_vcpu *vcpu, u64 *exit_code) > kvm_handle_pvm_sysreg(vcpu, exit_code)); > } > > -/** > - * Handler for protected floating-point and Advanced SIMD accesses. > - * > - * Returns true if the hypervisor has handled the exit, and control should go > - * back to the guest, or false if it hasn't. > - */ > -static bool kvm_handle_pvm_fpsimd(struct kvm_vcpu *vcpu, u64 *exit_code) > -{ > - /* Linux guests assume support for floating-point and Advanced SIMD. */ > - BUILD_BUG_ON(!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_FP), > - PVM_ID_AA64PFR0_ALLOW)); > - BUILD_BUG_ON(!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_ASIMD), > - PVM_ID_AA64PFR0_ALLOW)); > - > - return kvm_hyp_handle_fpsimd(vcpu, exit_code); > -} > - > static const exit_handler_fn hyp_exit_handlers[] = { > [0 ... ESR_ELx_EC_MAX] = NULL, > [ESR_ELx_EC_CP15_32] = kvm_hyp_handle_cp15_32, > @@ -207,7 +190,7 @@ static const exit_handler_fn pvm_exit_handlers[] = { > [0 ... ESR_ELx_EC_MAX] = NULL, > [ESR_ELx_EC_SYS64] = kvm_handle_pvm_sys64, > [ESR_ELx_EC_SVE] = kvm_handle_pvm_restricted, > - [ESR_ELx_EC_FP_ASIMD] = kvm_handle_pvm_fpsimd, > + [ESR_ELx_EC_FP_ASIMD] = kvm_hyp_handle_fpsimd, > [ESR_ELx_EC_IABT_LOW] = kvm_hyp_handle_iabt_low, > [ESR_ELx_EC_DABT_LOW] = kvm_hyp_handle_dabt_low, > [ESR_ELx_EC_PAC] = kvm_hyp_handle_ptrauth, > -- > 2.36.0.512.ge40c2bad7a-goog >