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 X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B6E18C0650E for ; Wed, 3 Jul 2019 09:11:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9B7E92189E for ; Wed, 3 Jul 2019 09:11:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727262AbfGCJLH (ORCPT ); Wed, 3 Jul 2019 05:11:07 -0400 Received: from foss.arm.com ([217.140.110.172]:41974 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727103AbfGCJLD (ORCPT ); Wed, 3 Jul 2019 05:11:03 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1DE15344; Wed, 3 Jul 2019 02:11:02 -0700 (PDT) Received: from [10.1.31.185] (unknown [10.1.31.185]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D43CF3F246; Wed, 3 Jul 2019 02:11:00 -0700 (PDT) Subject: Re: [PATCH 28/59] KVM: arm64: nv: Respect the virtual HCR_EL2.NV1 bit setting From: Alexandru Elisei To: Marc Zyngier , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org Cc: Andre Przywara , Dave Martin References: <20190621093843.220980-1-marc.zyngier@arm.com> <20190621093843.220980-29-marc.zyngier@arm.com> Message-ID: <4e0f2630-2405-e0f2-c745-131e1027b3bc@arm.com> Date: Wed, 3 Jul 2019 10:10:59 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Content-Language: en-US Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On 7/2/19 5:32 PM, Alexandru Elisei wrote: > On 6/21/19 10:38 AM, Marc Zyngier wrote: >> From: Jintack Lim >> >> Forward ELR_EL1, SPSR_EL1 and VBAR_EL1 traps to the virtual EL2 if the >> virtual HCR_EL2.NV bit is set. > HCR_EL2.NV1? >> This is for recursive nested virtualization. >> >> Signed-off-by: Jintack Lim >> Signed-off-by: Marc Zyngier >> --- >> arch/arm64/include/asm/kvm_arm.h | 1 + >> arch/arm64/kvm/sys_regs.c | 19 +++++++++++++++++-- >> 2 files changed, 18 insertions(+), 2 deletions(-) >> >> diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h >> index d21486274eeb..55f4525c112c 100644 >> --- a/arch/arm64/include/asm/kvm_arm.h >> +++ b/arch/arm64/include/asm/kvm_arm.h >> @@ -24,6 +24,7 @@ >> >> /* Hyp Configuration Register (HCR) bits */ >> #define HCR_FWB (UL(1) << 46) >> +#define HCR_NV1 (UL(1) << 43) >> #define HCR_NV (UL(1) << 42) >> #define HCR_API (UL(1) << 41) >> #define HCR_APK (UL(1) << 40) >> diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c >> index 0f74b9277a86..beadebcfc888 100644 >> --- a/arch/arm64/kvm/sys_regs.c >> +++ b/arch/arm64/kvm/sys_regs.c >> @@ -473,8 +473,10 @@ static bool access_vm_reg(struct kvm_vcpu *vcpu, >> if (el12_reg(p) && forward_nv_traps(vcpu)) >> return false; >> >> - if (!el12_reg(p) && forward_vm_traps(vcpu, p)) >> - return kvm_inject_nested_sync(vcpu, kvm_vcpu_get_hsr(vcpu)); >> + if (!el12_reg(p) && forward_vm_traps(vcpu, p)) { >> + kvm_inject_nested_sync(vcpu, kvm_vcpu_get_hsr(vcpu)); >> + return false; >> + } >> >> BUG_ON(!vcpu_mode_el2(vcpu) && !p->is_write); >> >> @@ -1643,6 +1645,13 @@ static bool access_sp_el1(struct kvm_vcpu *vcpu, >> return true; >> } >> >> + >> +/* This function is to support the recursive nested virtualization */ >> +static bool forward_nv1_traps(struct kvm_vcpu *vcpu, struct sys_reg_params *p) > Why the struct sys_reg_params *p argument? It isn't used by the function. >> +{ >> + return forward_traps(vcpu, HCR_NV1); >> +} >> + >> static bool access_elr(struct kvm_vcpu *vcpu, >> struct sys_reg_params *p, >> const struct sys_reg_desc *r) >> @@ -1650,6 +1659,9 @@ static bool access_elr(struct kvm_vcpu *vcpu, >> if (el12_reg(p) && forward_nv_traps(vcpu)) >> return false; >> >> + if (!el12_reg(p) && forward_nv1_traps(vcpu, p)) >> + return false; >> + >> if (p->is_write) >> vcpu->arch.ctxt.gp_regs.elr_el1 = p->regval; >> else >> @@ -1665,6 +1677,9 @@ static bool access_spsr(struct kvm_vcpu *vcpu, >> if (el12_reg(p) && forward_nv_traps(vcpu)) >> return false; >> >> + if (!el12_reg(p) && forward_nv1_traps(vcpu, p)) >> + return false; >> + >> if (p->is_write) >> vcpu->arch.ctxt.gp_regs.spsr[KVM_SPSR_EL1] = p->regval; >> else > The commit message mentions VBAR_EL1, but there's no change related to it. > Parhaps you're missing this (build tested only): > > diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c > index bd21f0f45a86..082dc31ff533 100644 > --- a/arch/arm64/kvm/sys_regs.c > +++ b/arch/arm64/kvm/sys_regs.c > @@ -401,6 +401,12 @@ static bool el12_reg(struct sys_reg_params *p) >         return (p->Op1 == 5); >  } >   > +/* This function is to support the recursive nested virtualization */ > +static bool forward_nv1_traps(struct kvm_vcpu *vcpu, struct sys_reg_params *p) > +{ > +       return forward_traps(vcpu, HCR_NV1); > +} > + >  static bool access_rw(struct kvm_vcpu *vcpu, >                       struct sys_reg_params *p, >                       const struct sys_reg_desc *r) > @@ -408,6 +414,10 @@ static bool access_rw(struct kvm_vcpu *vcpu, >         if (el12_reg(p) && forward_nv_traps(vcpu)) >                 return false; >   > +       if (sys_reg(p->Op0, p->Op1, p->CRn, p->CRm, p->Op2) == SYS_VBAR_EL1 && > +           forward_nv1_traps(vcpu, p)) Ahem... this is probably better: +       if (r->reg == VBAR_EL1 && forward_nv1_traps(vcpu, p)) > +               return false; > + >         if (p->is_write) >                 vcpu_write_sys_reg(vcpu, p->regval, r->reg); >         else > @@ -1794,12 +1804,6 @@ static bool forward_ttlb_traps(struct kvm_vcpu *vcpu) >         return forward_traps(vcpu, HCR_TTLB); >  } >   > -/* This function is to support the recursive nested virtualization */ > -static bool forward_nv1_traps(struct kvm_vcpu *vcpu, struct sys_reg_params *p) > -{ > -       return forward_traps(vcpu, HCR_NV1); > -} > - >  static bool access_elr(struct kvm_vcpu *vcpu, >                        struct sys_reg_params *p, >                        const struct sys_reg_desc *r) >