From patchwork Mon Jul 8 15:44:34 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 13726746 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6F074143C45; Mon, 8 Jul 2024 15:44:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720453495; cv=none; b=A0xjE23VXgCzpFTh0+ghW6sqf1C1MuUiauxtZmXRt04dDz3AgWl/8GlnVzZ2as3QSu+533wIXCBGpVvA+MV4ZzgBjPTlukb6MMYVEUW3AxKSo3T1VhMUVF8305XUyxsszWjsXDNH0F5cj8q0Ym2Yxe0NkM52Y+BFeHIiSqVfw0w= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720453495; c=relaxed/simple; bh=D8Xbgc7QO/XpodPOM7J+nYMvERnS5AGZFqZ3iGgsOI8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=DOdfPNyV6R7/rtMLSOcUisBxhQObnhPcBDz/+lX59cu21fcOJd+D9N+LoSdBndOJV0aWo2JCgv71Hv48THppK4LuWiHeMPbHxNEw/jRpkUwOu8aTyNM5Vohj1OnvpIER+qDBUgACnjG5e3qH+yvNv/aMjA41YIBm2fETGQWuwOs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=sy+dVDPZ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="sy+dVDPZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1F4CBC4AF0E; Mon, 8 Jul 2024 15:44:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1720453495; bh=D8Xbgc7QO/XpodPOM7J+nYMvERnS5AGZFqZ3iGgsOI8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sy+dVDPZuObk3y6KRA2ju03xHq6CjPmdWBMsw4WfVH1PsdpAahgW+4AwT0gcYV5Pp +DlXI6AV+vKec+cdXoNuDOT5giGR/Nz0XKYStFIz+IDX5HkI35I3AHcbr/RM4TzH8B 5InaSad+TtFVJD79Uj32s3doF597kJ3e0xJ/QK7eODnUYnYghnzc+XAmZ4Y90bRs9J LMNvNsj8amZtv3Ib/dkREKfXWyog+lsO/7woOWcEdQbnRu9L9rh4qJhT/JFr8KT1CG OPaIBuC4P38q3OVB3XUxbcF+975CpBu2zGwH0V4HM2PxDaH+Mcmd+0oK/JJ6F5qo0W CpwHKLV+NYx0A== 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 1sQqXt-00Ae1P-1A; Mon, 08 Jul 2024 16:44:53 +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 3/7] KVM: arm64: Add save/restore support for FPMR Date: Mon, 8 Jul 2024 16:44:34 +0100 Message-Id: <20240708154438.1218186-4-maz@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240708154438.1218186-1-maz@kernel.org> References: <20240708154438.1218186-1-maz@kernel.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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 Just like the rest of the FP/SIMD state, FPMR needs to be context switched. The only interesting thing here is that we need to treat the pKVM part a bit differently, as the host FP state is never written back to the vcpu thread, but instead stored locally and eagerly restored. Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_host.h | 10 ++++++++++ arch/arm64/kvm/fpsimd.c | 1 + arch/arm64/kvm/hyp/nvhe/hyp-main.c | 4 ++++ arch/arm64/kvm/hyp/nvhe/switch.c | 10 ++++++++++ arch/arm64/kvm/hyp/vhe/switch.c | 4 ++++ 5 files changed, 29 insertions(+) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index a14c18e8b173a..764d23082eb91 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -599,6 +599,16 @@ struct kvm_host_data { struct cpu_sve_state *sve_state; }; + union { + /* HYP VA pointer to the host storage for FPMR */ + u64 *fpmr_ptr; + /* + * Used by pKVM only, as it needs to provide storage + * for the host + */ + u64 fpmr; + }; + /* Ownership of the FP regs */ enum { FP_STATE_FREE, diff --git a/arch/arm64/kvm/fpsimd.c b/arch/arm64/kvm/fpsimd.c index 4cb8ad5d69a80..ea5484ce1f3ba 100644 --- a/arch/arm64/kvm/fpsimd.c +++ b/arch/arm64/kvm/fpsimd.c @@ -63,6 +63,7 @@ void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu) */ *host_data_ptr(fp_owner) = FP_STATE_HOST_OWNED; *host_data_ptr(fpsimd_state) = kern_hyp_va(¤t->thread.uw.fpsimd_state); + *host_data_ptr(fpmr_ptr) = kern_hyp_va(¤t->thread.uw.fpmr); vcpu_clear_flag(vcpu, HOST_SVE_ENABLED); if (read_sysreg(cpacr_el1) & CPACR_EL1_ZEN_EL0EN) diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c index f43d845f3c4ec..6b14a2c13e287 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -78,6 +78,10 @@ static void fpsimd_sve_sync(struct kvm_vcpu *vcpu) else __fpsimd_restore_state(*host_data_ptr(fpsimd_state)); + if (system_supports_fpmr() && + kvm_has_feat(kern_hyp_va(vcpu->kvm), ID_AA64PFR2_EL1, FPMR, IMP)) + write_sysreg_s(*host_data_ptr(fpmr), SYS_FPMR); + *host_data_ptr(fp_owner) = FP_STATE_HOST_OWNED; } diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c index 6af179c6356d6..47d24ecd68fec 100644 --- a/arch/arm64/kvm/hyp/nvhe/switch.c +++ b/arch/arm64/kvm/hyp/nvhe/switch.c @@ -198,6 +198,16 @@ static void kvm_hyp_save_fpsimd_host(struct kvm_vcpu *vcpu) } else { __fpsimd_save_state(*host_data_ptr(fpsimd_state)); } + + if (system_supports_fpmr() && + kvm_has_feat(kern_hyp_va(vcpu->kvm), ID_AA64PFR2_EL1, FPMR, IMP)) { + u64 fpmr = read_sysreg_s(SYS_FPMR); + + if (unlikely(is_protected_kvm_enabled())) + *host_data_ptr(fpmr) = fpmr; + else + **host_data_ptr(fpmr_ptr) = fpmr; + } } static const exit_handler_fn hyp_exit_handlers[] = { diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c index 77010b76c150f..a307c1d5ac874 100644 --- a/arch/arm64/kvm/hyp/vhe/switch.c +++ b/arch/arm64/kvm/hyp/vhe/switch.c @@ -312,6 +312,10 @@ static bool kvm_hyp_handle_eret(struct kvm_vcpu *vcpu, u64 *exit_code) static void kvm_hyp_save_fpsimd_host(struct kvm_vcpu *vcpu) { __fpsimd_save_state(*host_data_ptr(fpsimd_state)); + + if (system_supports_fpmr() && + kvm_has_feat(vcpu->kvm, ID_AA64PFR2_EL1, FPMR, IMP)) + **host_data_ptr(fpmr_ptr) = read_sysreg_s(SYS_FPMR); } static bool kvm_hyp_handle_tlbi_el2(struct kvm_vcpu *vcpu, u64 *exit_code)