From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Zyngier Subject: Re: [PATCH v4 27/40] KVM: arm64: Prepare to handle deferred save/restore of ELR_EL1 Date: Wed, 21 Feb 2018 15:08:14 +0000 Message-ID: <86606ql6sh.wl-marc.zyngier@arm.com> References: <20180215210332.8648-1-christoffer.dall@linaro.org> <20180215210332.8648-28-christoffer.dall@linaro.org> Mime-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Andrew Jones , kvm@vger.kernel.org, Tomasz Nowicki , kvmarm@lists.cs.columbia.edu, Julien Grall , Yury Norov , linux-arm-kernel@lists.infradead.org, Dave Martin , Shih-Wei Li To: Christoffer Dall Return-path: In-Reply-To: <20180215210332.8648-28-christoffer.dall@linaro.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org List-Id: kvm.vger.kernel.org On Thu, 15 Feb 2018 21:03:19 +0000, Christoffer Dall wrote: > > ELR_EL1 is not used by a VHE host kernel and can be deferred, but we > need to rework the accesses to this register to access the latest value > depending on whether or not guest system registers are loaded on the CPU > or only reside in memory. > > Signed-off-by: Christoffer Dall > --- > > Notes: > Changes since v2: > - New patch (deferred register handling has been reworked) > > arch/arm64/include/asm/kvm_emulate.h | 18 +++++++++++++++++- > arch/arm64/kvm/inject_fault.c | 4 ++-- > 2 files changed, 19 insertions(+), 3 deletions(-) > > diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h > index 47c2406755fa..9cb13b23c7a1 100644 > --- a/arch/arm64/include/asm/kvm_emulate.h > +++ b/arch/arm64/include/asm/kvm_emulate.h > @@ -90,11 +90,27 @@ static inline unsigned long *vcpu_pc(const struct kvm_vcpu *vcpu) > return (unsigned long *)&vcpu_gp_regs(vcpu)->regs.pc; > } > > -static inline unsigned long *vcpu_elr_el1(const struct kvm_vcpu *vcpu) > +static inline unsigned long *__vcpu_elr_el1(const struct kvm_vcpu *vcpu) > { > return (unsigned long *)&vcpu_gp_regs(vcpu)->elr_el1; > } > > +static inline unsigned long vcpu_read_elr_el1(const struct kvm_vcpu *vcpu) > +{ > + if (vcpu->arch.sysregs_loaded_on_cpu) > + return read_sysreg_el1(elr); > + else > + return *__vcpu_elr_el1(vcpu); > +} > + > +static inline void vcpu_write_elr_el1(const struct kvm_vcpu *vcpu, unsigned long v) > +{ > + if (vcpu->arch.sysregs_loaded_on_cpu) > + write_sysreg_el1(v, elr); > + else > + *__vcpu_elr_el1(vcpu) = v; > +} > + > static inline unsigned long *vcpu_cpsr(const struct kvm_vcpu *vcpu) > { > return (unsigned long *)&vcpu_gp_regs(vcpu)->regs.pstate; > diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c > index 8dda1edae727..cc13b6f5ad11 100644 > --- a/arch/arm64/kvm/inject_fault.c > +++ b/arch/arm64/kvm/inject_fault.c > @@ -67,7 +67,7 @@ static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr > bool is_aarch32 = vcpu_mode_is_32bit(vcpu); > u32 esr = 0; > > - *vcpu_elr_el1(vcpu) = *vcpu_pc(vcpu); > + vcpu_write_elr_el1(vcpu, *vcpu_pc(vcpu)); > *vcpu_pc(vcpu) = get_except_vector(vcpu, except_type_sync); > > *vcpu_cpsr(vcpu) = PSTATE_FAULT_BITS_64; > @@ -102,7 +102,7 @@ static void inject_undef64(struct kvm_vcpu *vcpu) > unsigned long cpsr = *vcpu_cpsr(vcpu); > u32 esr = (ESR_ELx_EC_UNKNOWN << ESR_ELx_EC_SHIFT); > > - *vcpu_elr_el1(vcpu) = *vcpu_pc(vcpu); > + vcpu_write_elr_el1(vcpu, *vcpu_pc(vcpu)); > *vcpu_pc(vcpu) = get_except_vector(vcpu, except_type_sync); > > *vcpu_cpsr(vcpu) = PSTATE_FAULT_BITS_64; > -- > 2.14.2 > Reviewed-by: Marc Zyngier M. -- Jazz is not dead, it just smell funny.