From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Axtens Date: Fri, 26 Feb 2021 05:01:45 +0000 Subject: Re: [PATCH v2 01/37] KVM: PPC: Book3S 64: remove unused kvmppc_h_protect argument Message-Id: <878s7ba0cm.fsf@linkitivity.dja.id.au> List-Id: References: <20210225134652.2127648-1-npiggin@gmail.com> <20210225134652.2127648-2-npiggin@gmail.com> In-Reply-To: <20210225134652.2127648-2-npiggin@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Nicholas Piggin , kvm-ppc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org, Nicholas Piggin Hi Nick, > The va argument is not used in the function or set by its asm caller, > so remove it to be safe. Huh, so it isn't. I tracked the original implementation down to commit a8606e20e41a ("KVM: PPC: Handle some PAPR hcalls in the kernel") where paulus first added the ability to handle it in the kernel - there it takes a va argument but even then doesn't do anything with it. ajd also pointed out that we don't pass a va when linux is running as a guest, and LoPAR does not mention va as an argument. One small nit: checkpatch is complaining about spaces vs tabs: ERROR: code indent should use tabs where possible #25: FILE: arch/powerpc/include/asm/kvm_ppc.h:770: + unsigned long pte_index, unsigned long avpn);$ WARNING: please, no spaces at the start of a line #25: FILE: arch/powerpc/include/asm/kvm_ppc.h:770: + unsigned long pte_index, unsigned long avpn);$ Once that is resolved, Reviewed-by: Daniel Axtens Kind regards, Daniel Axtens > Signed-off-by: Nicholas Piggin > --- > arch/powerpc/include/asm/kvm_ppc.h | 3 +-- > arch/powerpc/kvm/book3s_hv_rm_mmu.c | 3 +-- > 2 files changed, 2 insertions(+), 4 deletions(-) > > diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h > index 8aacd76bb702..9531b1c1b190 100644 > --- a/arch/powerpc/include/asm/kvm_ppc.h > +++ b/arch/powerpc/include/asm/kvm_ppc.h > @@ -767,8 +767,7 @@ long kvmppc_h_remove(struct kvm_vcpu *vcpu, unsigned long flags, > unsigned long pte_index, unsigned long avpn); > long kvmppc_h_bulk_remove(struct kvm_vcpu *vcpu); > long kvmppc_h_protect(struct kvm_vcpu *vcpu, unsigned long flags, > - unsigned long pte_index, unsigned long avpn, > - unsigned long va); > + unsigned long pte_index, unsigned long avpn); > long kvmppc_h_read(struct kvm_vcpu *vcpu, unsigned long flags, > unsigned long pte_index); > long kvmppc_h_clear_ref(struct kvm_vcpu *vcpu, unsigned long flags, > diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c > index 88da2764c1bb..7af7c70f1468 100644 > --- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c > +++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c > @@ -673,8 +673,7 @@ long kvmppc_h_bulk_remove(struct kvm_vcpu *vcpu) > } > > long kvmppc_h_protect(struct kvm_vcpu *vcpu, unsigned long flags, > - unsigned long pte_index, unsigned long avpn, > - unsigned long va) > + unsigned long pte_index, unsigned long avpn) > { > struct kvm *kvm = vcpu->kvm; > __be64 *hpte; > -- > 2.23.0 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 202EBC433E6 for ; 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[2001:44b8:1113:6700:7ad2:5bb3:4fd4:d737]) by smtp.gmail.com with ESMTPSA id h8sm7251059pfv.154.2021.02.25.21.01.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 25 Feb 2021 21:01:49 -0800 (PST) From: Daniel Axtens To: Nicholas Piggin , kvm-ppc@vger.kernel.org Subject: Re: [PATCH v2 01/37] KVM: PPC: Book3S 64: remove unused kvmppc_h_protect argument In-Reply-To: <20210225134652.2127648-2-npiggin@gmail.com> References: <20210225134652.2127648-1-npiggin@gmail.com> <20210225134652.2127648-2-npiggin@gmail.com> Date: Fri, 26 Feb 2021 16:01:45 +1100 Message-ID: <878s7ba0cm.fsf@linkitivity.dja.id.au> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@lists.ozlabs.org, Nicholas Piggin Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Hi Nick, > The va argument is not used in the function or set by its asm caller, > so remove it to be safe. Huh, so it isn't. I tracked the original implementation down to commit a8606e20e41a ("KVM: PPC: Handle some PAPR hcalls in the kernel") where paulus first added the ability to handle it in the kernel - there it takes a va argument but even then doesn't do anything with it. ajd also pointed out that we don't pass a va when linux is running as a guest, and LoPAR does not mention va as an argument. One small nit: checkpatch is complaining about spaces vs tabs: ERROR: code indent should use tabs where possible #25: FILE: arch/powerpc/include/asm/kvm_ppc.h:770: + unsigned long pte_index, unsigned long avpn);$ WARNING: please, no spaces at the start of a line #25: FILE: arch/powerpc/include/asm/kvm_ppc.h:770: + unsigned long pte_index, unsigned long avpn);$ Once that is resolved, Reviewed-by: Daniel Axtens Kind regards, Daniel Axtens > Signed-off-by: Nicholas Piggin > --- > arch/powerpc/include/asm/kvm_ppc.h | 3 +-- > arch/powerpc/kvm/book3s_hv_rm_mmu.c | 3 +-- > 2 files changed, 2 insertions(+), 4 deletions(-) > > diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h > index 8aacd76bb702..9531b1c1b190 100644 > --- a/arch/powerpc/include/asm/kvm_ppc.h > +++ b/arch/powerpc/include/asm/kvm_ppc.h > @@ -767,8 +767,7 @@ long kvmppc_h_remove(struct kvm_vcpu *vcpu, unsigned long flags, > unsigned long pte_index, unsigned long avpn); > long kvmppc_h_bulk_remove(struct kvm_vcpu *vcpu); > long kvmppc_h_protect(struct kvm_vcpu *vcpu, unsigned long flags, > - unsigned long pte_index, unsigned long avpn, > - unsigned long va); > + unsigned long pte_index, unsigned long avpn); > long kvmppc_h_read(struct kvm_vcpu *vcpu, unsigned long flags, > unsigned long pte_index); > long kvmppc_h_clear_ref(struct kvm_vcpu *vcpu, unsigned long flags, > diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c > index 88da2764c1bb..7af7c70f1468 100644 > --- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c > +++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c > @@ -673,8 +673,7 @@ long kvmppc_h_bulk_remove(struct kvm_vcpu *vcpu) > } > > long kvmppc_h_protect(struct kvm_vcpu *vcpu, unsigned long flags, > - unsigned long pte_index, unsigned long avpn, > - unsigned long va) > + unsigned long pte_index, unsigned long avpn) > { > struct kvm *kvm = vcpu->kvm; > __be64 *hpte; > -- > 2.23.0