From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de (cantor2.suse.de [195.135.220.15]) (using TLSv1 with cipher ADH-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 251912C00AD for ; Thu, 30 Jan 2014 04:11:42 +1100 (EST) Message-ID: <52E93649.3080000@suse.de> Date: Wed, 29 Jan 2014 18:11:37 +0100 From: Alexander Graf MIME-Version: 1.0 To: "Aneesh Kumar K.V" Subject: Re: [RFC PATCH 07/10] KVM: PPC: BOOK3S: PR: Emulate facility status and control register References: <1390927455-3312-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1390927455-3312-8-git-send-email-aneesh.kumar@linux.vnet.ibm.com> In-Reply-To: <1390927455-3312-8-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: paulus@samba.org, linuxppc-dev@lists.ozlabs.org, kvm-ppc@vger.kernel.org, kvm@vger.kernel.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 01/28/2014 05:44 PM, Aneesh Kumar K.V wrote: > We allow priv-mode update of this. The guest value is saved in fscr, > and the value actually used is saved in shadow_fscr. shadow_fscr > only contains values that are allowed by the host. On > facility unavailable interrupt, if the facility is allowed by fscr > but disabled in shadow_fscr we need to emulate the support. Currently > all but EBB is disabled. We still don't support performance monitoring > in PR guest. > > Signed-off-by: Aneesh Kumar K.V > --- > arch/powerpc/include/asm/kvm_book3s_asm.h | 1 + > arch/powerpc/include/asm/kvm_host.h | 1 + > arch/powerpc/kernel/asm-offsets.c | 2 ++ > arch/powerpc/kvm/book3s_emulate.c | 16 ++++++++++++++++ > arch/powerpc/kvm/book3s_interrupts.S | 25 ++++++++++++++++++++++--- > 5 files changed, 42 insertions(+), 3 deletions(-) > > diff --git a/arch/powerpc/include/asm/kvm_book3s_asm.h b/arch/powerpc/include/asm/kvm_book3s_asm.h > index 192917d2239c..abd42523ad93 100644 > --- a/arch/powerpc/include/asm/kvm_book3s_asm.h > +++ b/arch/powerpc/include/asm/kvm_book3s_asm.h > @@ -103,6 +103,7 @@ struct kvmppc_host_state { > #ifdef CONFIG_PPC_BOOK3S_64 > u64 cfar; > u64 ppr; > + u64 host_fscr; > #endif > }; > > diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h > index e0b13aca98e6..f4be7be14330 100644 > --- a/arch/powerpc/include/asm/kvm_host.h > +++ b/arch/powerpc/include/asm/kvm_host.h > @@ -478,6 +478,7 @@ struct kvm_vcpu_arch { > ulong ppr; > ulong pspb; > ulong fscr; > + ulong shadow_fscr; > ulong tfhar; > ulong tfiar; > ulong texasr; > diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c > index 2c2227da6917..7484676b8f25 100644 > --- a/arch/powerpc/kernel/asm-offsets.c > +++ b/arch/powerpc/kernel/asm-offsets.c > @@ -525,6 +525,7 @@ int main(void) > DEFINE(VCPU_CFAR, offsetof(struct kvm_vcpu, arch.cfar)); > DEFINE(VCPU_PPR, offsetof(struct kvm_vcpu, arch.ppr)); > DEFINE(VCPU_FSCR, offsetof(struct kvm_vcpu, arch.fscr)); > + DEFINE(VCPU_SHADOW_FSCR, offsetof(struct kvm_vcpu, arch.shadow_fscr)); > DEFINE(VCPU_PSPB, offsetof(struct kvm_vcpu, arch.pspb)); > DEFINE(VCPU_TFHAR, offsetof(struct kvm_vcpu, arch.tfhar)); > DEFINE(VCPU_TFIAR, offsetof(struct kvm_vcpu, arch.tfiar)); > @@ -626,6 +627,7 @@ int main(void) > #ifdef CONFIG_PPC_BOOK3S_64 > HSTATE_FIELD(HSTATE_CFAR, cfar); > HSTATE_FIELD(HSTATE_PPR, ppr); > + HSTATE_FIELD(HSTATE_FSCR, host_fscr); > #endif /* CONFIG_PPC_BOOK3S_64 */ > > #else /* CONFIG_PPC_BOOK3S */ > diff --git a/arch/powerpc/kvm/book3s_emulate.c b/arch/powerpc/kvm/book3s_emulate.c > index 7f25adbd2590..60d0b6b745e7 100644 > --- a/arch/powerpc/kvm/book3s_emulate.c > +++ b/arch/powerpc/kvm/book3s_emulate.c > @@ -468,6 +468,19 @@ int kvmppc_core_emulate_mtspr_pr(struct kvm_vcpu *vcpu, int sprn, ulong spr_val) > case SPRN_MSSSR0: > case SPRN_DABR: > break; > + case SPRN_FSCR: > + { > + ulong host_fscr = mfspr(SPRN_FSCR); > + /* > + * We disable FSCR_EBB for pr guest. TAR and DSCR are always > + * enabled. > + */ > + if (spr_val & ~(FSCR_TAR|FSCR_DSCR|FSCR_EBB)) > + pr_info("KVM: invalud FSCR value 0x%lx", spr_val); Is this worth printing at all? If it is, it's probably more of a pr_debug(). Also s/invalud/invalid/. Alex > + vcpu->arch.fscr = spr_val & (FSCR_TAR|FSCR_DSCR); > + vcpu->arch.shadow_fscr = vcpu->arch.fscr & host_fscr; > + break; > + } > unprivileged: > default: > printk(KERN_INFO "KVM: invalid SPR write: %d\n", sprn); > @@ -591,6 +604,9 @@ int kvmppc_core_emulate_mfspr_pr(struct kvm_vcpu *vcpu, int sprn, ulong *spr_val > */ > *spr_val = 0; > break; > + case SPRN_FSCR: > + *spr_val = vcpu->arch.fscr; > + break; > default: > unprivileged: > printk(KERN_INFO "KVM: invalid SPR read: %d\n", sprn); > diff --git a/arch/powerpc/kvm/book3s_interrupts.S b/arch/powerpc/kvm/book3s_interrupts.S > index f779450cb07c..fcbdf4817301 100644 > --- a/arch/powerpc/kvm/book3s_interrupts.S > +++ b/arch/powerpc/kvm/book3s_interrupts.S > @@ -107,6 +107,14 @@ kvm_start_lightweight: > ld r3, VCPU_SHARED(r4) > ld r3, VCPU_SHARED_SPRG3(r3) > mtspr SPRN_SPRG3, r3 > + > +BEGIN_FTR_SECTION > + mfspr r3,SPRN_FSCR > + PPC_STL r3, HSTATE_FSCR(r13) > + > + PPC_LL r3, VCPU_SHADOW_FSCR(r4) > + mtspr SPRN_FSCR, r3 > +END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) > #endif /* CONFIG_PPC_BOOK3S_64 */ > > PPC_LL r4, VCPU_SHADOW_MSR(r4) /* get shadow_msr */ > @@ -148,6 +156,9 @@ kvm_start_lightweight: > bl FUNC(kvmppc_copy_from_svcpu) > nop > > + /* R7 = vcpu */ > + PPC_LL r7, GPR4(r1) > + > #ifdef CONFIG_PPC_BOOK3S_64 > /* > * Reload kernel SPRG3 value. > @@ -155,10 +166,18 @@ kvm_start_lightweight: > */ > ld r3, PACA_SPRG3(r13) > mtspr SPRN_SPRG3, r3 > -#endif /* CONFIG_PPC_BOOK3S_64 */ > +BEGIN_FTR_SECTION > + /* > + * Save the current fscr in shadow fscr > + */ > + mfspr r3,SPRN_FSCR > + PPC_STL r3, VCPU_SHADOW_FSCR(r7) > > - /* R7 = vcpu */ > - PPC_LL r7, GPR4(r1) > + PPC_LL r3, HSTATE_FSCR(r13) > + mtspr SPRN_FSCR, r3 > +END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) > + > +#endif /* CONFIG_PPC_BOOK3S_64 */ > > PPC_STL r14, VCPU_GPR(R14)(r7) > PPC_STL r15, VCPU_GPR(R15)(r7)