From mboxrd@z Thu Jan 1 00:00:00 1970 From: yezengruan Subject: Re: [PATCH 3/5] KVM: arm64: Support pvlock preempted via shared structure Date: Thu, 26 Dec 2019 16:33:28 +0800 Message-ID: <31f9d0b2-1366-26f9-2628-61583fb4a50d__18679.9332661153$1577349260$gmane$org@huawei.com> References: <20191217135549.3240-1-yezengruan@huawei.com> <20191217135549.3240-4-yezengruan@huawei.com> <20191217143301.GC38811@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20191217143301.GC38811@arm.com> Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" To: Steven Price Cc: Mark Rutland , "daniel.lezcano@linaro.org" , "kvm@vger.kernel.org" , "linux-doc@vger.kernel.org" , "maz@kernel.org" , Suzuki Poulose , "linux-kernel@vger.kernel.org" , "virtualization@lists.linux-foundation.org" , James Morse , "julien.thierry.kdev@gmail.com" , Catalin Marinas , "linux@armlinux.org.uk" , "will@kernel.org" , "kvmarm@lists.cs.columbia.edu" , "linux-arm-kernel@lists.infradead.org" List-Id: virtualization@lists.linuxfoundation.org Hi Steve, On 2019/12/17 22:33, Steven Price wrote: > On Tue, Dec 17, 2019 at 01:55:47PM +0000, yezengruan@huawei.com wrote: >> From: Zengruan Ye >> >> Implement the service call for configuring a shared structure between a >> vcpu and the hypervisor in which the hypervisor can tell the vcpu is >> running or not. >> >> The preempted field is zero if 1) some old KVM deos not support this filed. >> 2) the vcpu is not preempted. Other values means the vcpu has been preempted. >> >> Signed-off-by: Zengruan Ye >> --- >> arch/arm/include/asm/kvm_host.h | 13 +++++++++++++ >> arch/arm64/include/asm/kvm_host.h | 17 +++++++++++++++++ >> arch/arm64/kvm/Makefile | 1 + >> virt/kvm/arm/arm.c | 8 ++++++++ >> virt/kvm/arm/hypercalls.c | 4 ++++ >> virt/kvm/arm/pvlock.c | 21 +++++++++++++++++++++ >> 6 files changed, 64 insertions(+) >> create mode 100644 virt/kvm/arm/pvlock.c >> >> diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h >> index 556cd818eccf..098375f1c89e 100644 >> --- a/arch/arm/include/asm/kvm_host.h >> +++ b/arch/arm/include/asm/kvm_host.h >> @@ -356,6 +356,19 @@ static inline bool kvm_arm_is_pvtime_enabled(struct kvm_vcpu_arch *vcpu_arch) >> return false; >> } >> >> +static inline void kvm_arm_pvlock_preempted_init(struct kvm_vcpu_arch *vcpu_arch) >> +{ >> +} >> + >> +static inline bool kvm_arm_is_pvlock_preempted_ready(struct kvm_vcpu_arch *vcpu_arch) >> +{ >> + return false; >> +} >> + >> +static inline void kvm_update_pvlock_preempted(struct kvm_vcpu *vcpu, u64 preempted) >> +{ >> +} >> + >> void kvm_mmu_wp_memory_region(struct kvm *kvm, int slot); >> >> struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr); >> diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h >> index c61260cf63c5..d9b2a21a87ac 100644 >> --- a/arch/arm64/include/asm/kvm_host.h >> +++ b/arch/arm64/include/asm/kvm_host.h >> @@ -354,6 +354,11 @@ struct kvm_vcpu_arch { >> u64 last_steal; >> gpa_t base; >> } steal; >> + >> + /* Guest PV lock state */ >> + struct { >> + gpa_t base; >> + } pv; >> }; >> >> /* Pointer to the vcpu's SVE FFR for sve_{save,load}_state() */ >> @@ -515,6 +520,18 @@ static inline bool kvm_arm_is_pvtime_enabled(struct kvm_vcpu_arch *vcpu_arch) >> return (vcpu_arch->steal.base != GPA_INVALID); >> } >> >> +static inline void kvm_arm_pvlock_preempted_init(struct kvm_vcpu_arch *vcpu_arch) >> +{ >> + vcpu_arch->pv.base = GPA_INVALID; >> +} >> + >> +static inline bool kvm_arm_is_pvlock_preempted_ready(struct kvm_vcpu_arch *vcpu_arch) >> +{ >> + return (vcpu_arch->pv.base != GPA_INVALID); >> +} >> + >> +void kvm_update_pvlock_preempted(struct kvm_vcpu *vcpu, u64 preempted); >> + >> void kvm_set_sei_esr(struct kvm_vcpu *vcpu, u64 syndrome); >> >> struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr); >> diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile >> index 5ffbdc39e780..e4591f56d5f1 100644 >> --- a/arch/arm64/kvm/Makefile >> +++ b/arch/arm64/kvm/Makefile >> @@ -15,6 +15,7 @@ kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/arm.o $(KVM)/arm/mmu.o $(KVM)/arm/mmio. >> kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/psci.o $(KVM)/arm/perf.o >> kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/hypercalls.o >> kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/pvtime.o >> +kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/pvlock.o >> >> kvm-$(CONFIG_KVM_ARM_HOST) += inject_fault.o regmap.o va_layout.o >> kvm-$(CONFIG_KVM_ARM_HOST) += hyp.o hyp-init.o handle_exit.o >> diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c >> index 12e0280291ce..c562f62fdd45 100644 >> --- a/virt/kvm/arm/arm.c >> +++ b/virt/kvm/arm/arm.c >> @@ -383,6 +383,8 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) >> >> kvm_arm_pvtime_vcpu_init(&vcpu->arch); >> >> + kvm_arm_pvlock_preempted_init(&vcpu->arch); >> + >> return kvm_vgic_vcpu_init(vcpu); >> } >> >> @@ -421,6 +423,9 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) >> vcpu_set_wfx_traps(vcpu); >> >> vcpu_ptrauth_setup_lazy(vcpu); >> + >> + if (kvm_arm_is_pvlock_preempted_ready(&vcpu->arch)) >> + kvm_update_pvlock_preempted(vcpu, 0); >> } >> >> void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) >> @@ -434,6 +439,9 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) >> vcpu->cpu = -1; >> >> kvm_arm_set_running_vcpu(NULL); >> + >> + if (kvm_arm_is_pvlock_preempted_ready(&vcpu->arch)) >> + kvm_update_pvlock_preempted(vcpu, 1); >> } >> >> static void vcpu_power_off(struct kvm_vcpu *vcpu) >> diff --git a/virt/kvm/arm/hypercalls.c b/virt/kvm/arm/hypercalls.c >> index ff13871fd85a..5964982ccd05 100644 >> --- a/virt/kvm/arm/hypercalls.c >> +++ b/virt/kvm/arm/hypercalls.c >> @@ -65,6 +65,10 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) >> if (gpa != GPA_INVALID) >> val = gpa; >> break; >> + case ARM_SMCCC_HV_PV_LOCK_PREEMPTED: >> + vcpu->arch.pv.base = smccc_get_arg1(vcpu); >> + val = SMCCC_RET_SUCCESS; > > It would be useful to at least do some basic validation that the address > passed in is valid. Debugging problems with this interface will be hard > if it always returns success even if the address cannot be used. > > The second patch also states that the structure should be 64 byte > aligned, but there's nothing here to enforce that. Thanks for posting this. I'll update the code. > > Steve > >> + break; >> default: >> return kvm_psci_call(vcpu); >> } >> diff --git a/virt/kvm/arm/pvlock.c b/virt/kvm/arm/pvlock.c >> new file mode 100644 >> index 000000000000..c3464958b0f5 >> --- /dev/null >> +++ b/virt/kvm/arm/pvlock.c >> @@ -0,0 +1,21 @@ >> +/* SPDX-License-Identifier: GPL-2.0-only */ >> +/* >> + * Copyright(c) 2019 Huawei Technologies Co., Ltd >> + * Author: Zengruan Ye >> + */ >> + >> +#include >> +#include >> + >> +#include >> + >> +void kvm_update_pvlock_preempted(struct kvm_vcpu *vcpu, u64 preempted) >> +{ >> + u64 preempted_le; >> + u64 base; >> + struct kvm *kvm = vcpu->kvm; >> + >> + base = vcpu->arch.pv.base; >> + preempted_le = cpu_to_le64(preempted); >> + kvm_put_guest(kvm, base, preempted_le, u64); >> +} >> -- >> 2.19.1 >> >> > > . > Thanks, Zengruan