> -----Original Message----- > From: Marc Zyngier [mailto:maz@xxxxxxxxxx] > Sent: 15 January 2021 14:15 > To: Ard Biesheuvel <ardb@xxxxxxxxxx> > Cc: Linux ARM <linux-arm-kernel@xxxxxxxxxxxxxxxxxxx>; kvmarm > <kvmarm@xxxxxxxxxxxxxxxxxxxxx>; Shameerali Kolothum Thodi > <shameerali.kolothum.thodi@xxxxxxxxxx>; James Morse > <james.morse@xxxxxxx>; Julien Thierry <julien.thierry.kdev@xxxxxxxxx>; > Suzuki K Poulose <suzuki.poulose@xxxxxxx>; Android Kernel Team > <kernel-team@xxxxxxxxxxx> > Subject: Re: [PATCH v2 2/2] KVM: arm64: Workaround firmware wrongly > advertising GICv2-on-v3 compatibility > > On 2021-01-15 14:08, Ard Biesheuvel wrote: > > On Fri, 15 Jan 2021 at 15:03, Marc Zyngier <maz@xxxxxxxxxx> wrote: > > [...] > > >> diff --git a/arch/arm64/kvm/vgic/vgic-v3.c > >> b/arch/arm64/kvm/vgic/vgic-v3.c index 8e7bf3151057..67b27b47312b > >> 100644 > >> --- a/arch/arm64/kvm/vgic/vgic-v3.c > >> +++ b/arch/arm64/kvm/vgic/vgic-v3.c > >> @@ -584,8 +584,10 @@ early_param("kvm-arm.vgic_v4_enable", > >> early_gicv4_enable); > >> int vgic_v3_probe(const struct gic_kvm_info *info) { > >> u64 ich_vtr_el2 = kvm_call_hyp_ret(__vgic_v3_get_gic_config); > >> + bool has_v2; > >> int ret; > >> > >> + has_v2 = ich_vtr_el2 >> 63; > >> ich_vtr_el2 = (u32)ich_vtr_el2; > >> > >> /* > >> @@ -605,13 +607,15 @@ int vgic_v3_probe(const struct gic_kvm_info > >> *info) > >> gicv4_enable ? "en" : "dis"); > >> } > >> > >> + kvm_vgic_global_state.vcpu_base = 0; > >> + > >> if (!info->vcpu.start) { > >> kvm_info("GICv3: no GICV resource entry\n"); > >> - kvm_vgic_global_state.vcpu_base = 0; > >> + } else if (!has_v2) { > >> + pr_warn("CPU interface incapable of MMIO access\n"); > > > > Could we include FW_BUG here to stress that this is a firmware problem? > > Absolutely! That's what it now looks like: > > [ 2.648452] kvm [1]: IPA Size Limit: 40 bits > [ 2.649259] [Firmware Bug]: CPU interface incapable of MMIO access > [ 2.649620] kvm [1]: disabling GICv2 emulation > [ 2.650227] kvm [1]: GIC system register CPU interface enabled > [ 2.652004] kvm [1]: vgic interrupt IRQ9 > [ 2.655623] kvm [1]: VHE mode initialized successfully > > Updated version pushed out. Is there a v3 for this series? I couldn't find one. Anyways, tested this series on a D06 with faulty firmware and it is working as expected. FWIW, Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@xxxxxxxxxx> Thanks, Shameer > Thanks, > > M. > -- > Jazz is not dead. It just smells funny... _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
