From patchwork Fri Apr 20 16:46:36 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Martin X-Patchwork-Id: 10353237 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4AA1C600CC for ; Fri, 20 Apr 2018 16:47:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 28661287E6 for ; Fri, 20 Apr 2018 16:47:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1D3B1287ED; Fri, 20 Apr 2018 16:47:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 85EE8287E6 for ; Fri, 20 Apr 2018 16:47:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=trEn9bsx4P4rHBywoBNJnvTbTQHlZOgdU6fdKhy4Myw=; b=FE1zIEDWcekKk9sZ2z+2J4PlNX DPXrPnPM7x7446d3cadNk2susB4ljZ7d1hCzZDxQz9px74/5lR6VElE3LQ0ncoswUKZVDy036/C8S OieUDVb7M6Nt7AzMbVaZ5421SyF3C/HPi4HRckLw/HERKRBWHUkGOGHIiZ5aaodiD8BwZS2AseSXf oqE3KVtn7gBmig2eHkcKODHR6d3FE7HwY1megeu3Nsj144FwIG1hCZdgMEPikg8mMZWE0ZS6xgvXn Nn1Jb5lTeeZDCE7ut5Tm8ct8r/NE7/UsKQlW5sKCue6uvFLDxJVjOd2HH/8eOYjG0TzC0fUlFW+e4 3isRphgQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1f9ZBe-0005oQ-LD; Fri, 20 Apr 2018 16:47:02 +0000 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1f9ZBa-0005mn-Er for linux-arm-kernel@lists.infradead.org; Fri, 20 Apr 2018 16:47:00 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 754AB15AB; Fri, 20 Apr 2018 09:46:50 -0700 (PDT) Received: from e103592.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 8A8C23F59D; Fri, 20 Apr 2018 09:46:49 -0700 (PDT) From: Dave Martin To: kvmarm@lists.cs.columbia.edu Subject: [RFC PATCH 2/8] KVM: arm64: Convert lazy FPSIMD context switch trap to C Date: Fri, 20 Apr 2018 17:46:36 +0100 Message-Id: <1524242802-21163-3-git-send-email-Dave.Martin@arm.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1524242802-21163-1-git-send-email-Dave.Martin@arm.com> References: <1524242802-21163-1-git-send-email-Dave.Martin@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20180420_094658_579537_26202BBA X-CRM114-Status: GOOD ( 12.44 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Marc Zyngier , Christoffer Dall , linux-arm-kernel@lists.infradead.org, Ard Biesheuvel MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP To make the lazy FPSIMD context switch trap code easier to hack on, this patch converts it to C. This is not amazingly efficient, but the trap should typically only be taken once per host context switch. Signed-off-by: Dave Martin --- Since RFCv1: * Fix indentation to be consistent with the rest of the file. * Add missing ! to write back to sp with attempting to push regs. --- arch/arm64/kvm/hyp/entry.S | 57 +++++++++++++++++---------------------------- arch/arm64/kvm/hyp/switch.c | 24 +++++++++++++++++++ 2 files changed, 46 insertions(+), 35 deletions(-) diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S index e41a161..40f349b 100644 --- a/arch/arm64/kvm/hyp/entry.S +++ b/arch/arm64/kvm/hyp/entry.S @@ -172,40 +172,27 @@ ENTRY(__fpsimd_guest_restore) // x1: vcpu // x2-x29,lr: vcpu regs // vcpu x0-x1 on the stack - stp x2, x3, [sp, #-16]! - stp x4, lr, [sp, #-16]! - -alternative_if_not ARM64_HAS_VIRT_HOST_EXTN - mrs x2, cptr_el2 - bic x2, x2, #CPTR_EL2_TFP - msr cptr_el2, x2 -alternative_else - mrs x2, cpacr_el1 - orr x2, x2, #CPACR_EL1_FPEN - msr cpacr_el1, x2 -alternative_endif - isb - - mov x3, x1 - - ldr x0, [x3, #VCPU_HOST_CONTEXT] - kern_hyp_va x0 - add x0, x0, #CPU_GP_REG_OFFSET(CPU_FP_REGS) - bl __fpsimd_save_state - - add x2, x3, #VCPU_CONTEXT - add x0, x2, #CPU_GP_REG_OFFSET(CPU_FP_REGS) - bl __fpsimd_restore_state - - // Skip restoring fpexc32 for AArch64 guests - mrs x1, hcr_el2 - tbnz x1, #HCR_RW_SHIFT, 1f - ldr x4, [x3, #VCPU_FPEXC32_EL2] - msr fpexc32_el2, x4 -1: - ldp x4, lr, [sp], #16 - ldp x2, x3, [sp], #16 - ldp x0, x1, [sp], #16 - + stp x2, x3, [sp, #-144]! + stp x4, x5, [sp, #16] + stp x6, x7, [sp, #32] + stp x8, x9, [sp, #48] + stp x10, x11, [sp, #64] + stp x12, x13, [sp, #80] + stp x14, x15, [sp, #96] + stp x16, x17, [sp, #112] + stp x18, lr, [sp, #128] + + bl __hyp_switch_fpsimd + + ldp x4, x5, [sp, #16] + ldp x6, x7, [sp, #32] + ldp x8, x9, [sp, #48] + ldp x10, x11, [sp, #64] + ldp x12, x13, [sp, #80] + ldp x14, x15, [sp, #96] + ldp x16, x17, [sp, #112] + ldp x18, lr, [sp, #128] + ldp x0, x1, [sp, #144] + ldp x2, x3, [sp], #160 eret ENDPROC(__fpsimd_guest_restore) diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index d964523..c438ad8 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -499,6 +499,30 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu) return exit_code; } +void __hyp_text __hyp_switch_fpsimd(u64 esr __always_unused, + struct kvm_vcpu *vcpu) +{ + kvm_cpu_context_t *host_ctxt; + + if (has_vhe()) + write_sysreg(read_sysreg(cpacr_el1) | CPACR_EL1_FPEN, + cpacr_el1); + else + write_sysreg(read_sysreg(cptr_el2) & ~(u64)CPTR_EL2_TFP, + cptr_el2); + + isb(); + + host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context); + __fpsimd_save_state(&host_ctxt->gp_regs.fp_regs); + __fpsimd_restore_state(&vcpu->arch.ctxt.gp_regs.fp_regs); + + /* Skip restoring fpexc32 for AArch64 guests */ + if (!(read_sysreg(hcr_el2) & HCR_RW)) + write_sysreg(vcpu->arch.ctxt.sys_regs[FPEXC32_EL2], + fpexc32_el2); +} + static const char __hyp_panic_string[] = "HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n"; static void __hyp_text __hyp_call_panic_nvhe(u64 spsr, u64 elr, u64 par,