From patchwork Tue Aug 13 10:43:52 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 13761766 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 5FFD5C52D7B for ; Tue, 13 Aug 2024 10:45:04 +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: MIME-Version:Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=Zsp5nM7fv6OjupyR2T/QdWnL1FksLzxchxdOW9jwDNE=; b=QRcEph/ZLszSjnh+og68TuJyRB A875bjfEoakKKifi155AeGzYEa3Uge6Hjc9H6Vzgqd+UsTJRb9xuIxR5BcN/c5kyb06petFBbJtwL nyIV2sf9nWpdk0XZq4CFYAMSuyEeEc4+ZWVqdbh3x0GWDqIzfSadAP0Drm7BJwQRdMjtE8hSwNR8j 4qihyMrW+W+BuXVQfjuxhN13iIVItvPD40D2MXC2qAxB4uLnbnB9TQdFiSzlfHLuBTceL4awvB7HY KMaZkKXLhemq8ZVJW/R3MDhG9AE5eF46QCLGDJ6ZamOtd7m0GlQWvoz5lLSq8tBNSOCGgcxEwYszf 1M4huSNQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sdp1F-00000003NUY-38cQ; Tue, 13 Aug 2024 10:44:49 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sdp0c-00000003NES-2CrA for linux-arm-kernel@lists.infradead.org; Tue, 13 Aug 2024 10:44:12 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 0448161635; Tue, 13 Aug 2024 10:44:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A42C9C4AF0B; Tue, 13 Aug 2024 10:44:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1723545849; bh=KeAEfHGzQzII5PNpXANK31ac/qnVj2yuiImhA5avUVY=; h=From:To:Cc:Subject:Date:From; b=qHuxyvBdOdpzMhJavvgEjaLnFY81a+R8A2ajo4+t8Pbp11VG/QUxP1GvmjZBzBc/r ol9mB5kJ7ME4xMRa12S7lyAAowvNlSk/Xv4musANzFPo1ztszVk1DKoX6Tg6SgNyuH RqvcZoZ9RIJliDSH/4wNS5YA67toUUWbiBwpn8ws1QKvUptal7Fr2CbVfSisQfLbVV HUVlFaWN89I3kq592Tw+AV+IF+efDoL+uvS6OHYrpb5WjRsAkFkVrBasr60+7R/WqI dRdjYmZhuWTRv2vt0X5S+pIy1EUfUY/8sf5h/6WjnvMsrDT41aYTo/myVFa2vt2RF3 xJqVuAyW/c0tA== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1sdp0Z-003JD1-Kh; Tue, 13 Aug 2024 11:44:07 +0100 From: Marc Zyngier To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org Cc: James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Fuad Tabba , Joey Gouly , Mark Brown Subject: [PATCH v3 0/8] KVM: arm64: Add support for FP8 Date: Tue, 13 Aug 2024 11:43:52 +0100 Message-Id: <20240813104400.1956132-1-maz@kernel.org> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, james.morse@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.com, tabba@google.com, joey.gouly@arm.com, broonie@kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240813_034410_675284_6F34768E X-CRM114-Status: GOOD ( 13.81 ) 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 Although FP8 support was merged in 6.9, the KVM side was dropped, with no sign of it being picked up again. Given that its absence is getting in the way of NV upstreaming (HCRX_EL2 needs fleshing out), here's a small series addressing it. The support is following the save/restore model established for the rest of the FP code, with FPMR being tied to it. The sole additions are the handling of traps in a nested context, and the corresponding ID registers being made writable. As an extra cleanup, SVCR and FPMR are moved into the sysreg array. Patches are on top of v6.11-rc1. Note that this is compile-tested only, as I have no access to FP8 HW or model (and running NV in a model is not something I wish to entertain ever again). * From v2 [2] - Add missing kern_hyp_va() when dereferencing vcpu->kvm on nVHE setups * From v1 [1] - Correctly save/restore the guest state (duh), including pKVM (double duh) - Add a predicate for FPMR support in a VM, as this gets used more than twice... [1] https://lore.kernel.org/r/20240708154438.1218186-1-maz@kernel.org [2] https://lore.kernel.org/r/20240708154438.1218186-1-maz@kernel.org Marc Zyngier (8): KVM: arm64: Move SVCR into the sysreg array KVM: arm64: Add predicate for FPMR support in a VM KVM: arm64: Move FPMR into the sysreg array KVM: arm64: Add save/restore support for FPMR KVM: arm64: Honor trap routing for FPMR KVM: arm64: Expose ID_AA64FPFR0_EL1 as a writable ID reg KVM: arm64: Enable FP8 support when available and configured KVM: arm64: Expose ID_AA64PFR2_EL1 to userspace and guests arch/arm64/include/asm/kvm_host.h | 20 ++++++++++-- arch/arm64/kvm/emulate-nested.c | 8 +++++ arch/arm64/kvm/fpsimd.c | 5 +-- arch/arm64/kvm/hyp/include/hyp/switch.h | 3 ++ arch/arm64/kvm/hyp/nvhe/hyp-main.c | 9 ++++++ arch/arm64/kvm/hyp/nvhe/switch.c | 9 ++++++ arch/arm64/kvm/hyp/vhe/switch.c | 3 ++ arch/arm64/kvm/sys_regs.c | 42 +++++++++++++++++++++++-- 8 files changed, 92 insertions(+), 7 deletions(-)