when SError happen, kvm notifies user space to record the CPER, user space specifies and passes the contents of ESR_EL1 on taking a virtual SError interrupt to KVM, KVM enables virtual system error or asynchronous abort with this specifies syndrome. This patch modify the world-switch to restore VSESR_EL2, VSESR_EL2 saves the virtual SError syndrome, it becomes the ESR_EL1 value when HCR_EL2.VSE injects an SError. This register is added by the RAS Extensions. Changes since v3: (1) Move restore VSESR_EL2 value logic to a helper method (2) In the world-switch, not save VSESR_EL2, because no one cares the old VSESR_EL2 value (3) Add a new KVM_ARM_SEI ioctl to set the VSESR_EL2 value and pend a virtual system error Signed-off-by: Dongjiu Geng <gengdongjiu@xxxxxxxxxx> Signed-off-by: Quanming Wu <wuquanming@xxxxxxxxxx> --- Documentation/virtual/kvm/api.txt | 10 ++++++++++ arch/arm/include/asm/kvm_host.h | 1 + arch/arm/kvm/arm.c | 6 ++++++ arch/arm/kvm/guest.c | 5 +++++ arch/arm64/include/asm/esr.h | 2 ++ arch/arm64/include/asm/kvm_emulate.h | 10 ++++++++++ arch/arm64/include/asm/kvm_host.h | 2 ++ arch/arm64/include/asm/sysreg.h | 3 +++ arch/arm64/kvm/guest.c | 14 ++++++++++++++ arch/arm64/kvm/handle_exit.c | 25 +++++++++++++++++++------ arch/arm64/kvm/hyp/switch.c | 14 ++++++++++++++ include/uapi/linux/kvm.h | 8 ++++++++ 12 files changed, 94 insertions(+), 6 deletions(-) diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 3c248f7..852ac55 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -3377,6 +3377,16 @@ struct kvm_ppc_resize_hpt { __u32 pad; }; +4.104 KVM_ARM_SEI + +Capability: KVM_EXIT_SERROR_INTR +Architectures: arm/arm64 +Type: vcpu ioctl +Parameters: u64 (syndrome) +Returns: 0 in case of success + +Pend an virtual system error or asynchronous abort with user space specified. + 5. The kvm_run structure ------------------------ diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 31ee468..566292a 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -244,6 +244,7 @@ int kvm_arm_coproc_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *); int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run, int exception_index); +int kvm_vcpu_ioctl_sei(struct kvm_vcpu *vcpu, u64 *syndrome); static inline void __cpu_init_hyp_mode(phys_addr_t pgd_ptr, unsigned long hyp_stack_ptr, diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 96dba7c..2622501 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -987,6 +987,12 @@ long kvm_arch_vcpu_ioctl(struct file *filp, return -EFAULT; return kvm_arm_vcpu_has_attr(vcpu, &attr); } + case KVM_ARM_SEI: { + u64 syndrome; + if (copy_from_user(&syndrome, argp, sizeof(syndrome))) + return -EFAULT; + return kvm_vcpu_ioctl_sei(vcpu, &syndrome); + } default: return -EINVAL; } diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c index fa6182a..a610f8f 100644 --- a/arch/arm/kvm/guest.c +++ b/arch/arm/kvm/guest.c @@ -248,6 +248,11 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, return -EINVAL; } +int kvm_vcpu_ioctl_sei(struct kvm_vcpu *vcpu, u64 *syndrome); +{ + return 0; +} + int __attribute_const__ kvm_target_cpu(void) { switch (read_cpuid_part()) { diff --git a/arch/arm64/include/asm/esr.h b/arch/arm64/include/asm/esr.h index 22f9c90..d009c99 100644 --- a/arch/arm64/include/asm/esr.h +++ b/arch/arm64/include/asm/esr.h @@ -127,6 +127,8 @@ #define ESR_ELx_WFx_ISS_WFE (UL(1) << 0) #define ESR_ELx_xVC_IMM_MASK ((1UL << 16) - 1) +#define VSESR_ELx_IDS_ISS_MASK ((1UL << 25) - 1) + /* ESR value templates for specific events */ /* BRK instruction trap from AArch64 state */ diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index f5ea0ba..a3259a9 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -148,6 +148,16 @@ static inline u32 kvm_vcpu_get_hsr(const struct kvm_vcpu *vcpu) return vcpu->arch.fault.esr_el2; } +static inline u32 kvm_vcpu_get_vsesr(const struct kvm_vcpu *vcpu) +{ + return vcpu->arch.fault.vsesr_el2; +} + +static inline void kvm_vcpu_set_vsesr(struct kvm_vcpu *vcpu, unsigned long val) +{ + vcpu->arch.fault.vsesr_el2 = val; +} + static inline int kvm_vcpu_get_condition(const struct kvm_vcpu *vcpu) { u32 esr = kvm_vcpu_get_hsr(vcpu); diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index e7705e7..b6242fb 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -86,6 +86,7 @@ struct kvm_vcpu_fault_info { u32 esr_el2; /* Hyp Syndrom Register */ u64 far_el2; /* Hyp Fault Address Register */ u64 hpfar_el2; /* Hyp IPA Fault Address Register */ + u32 vsesr_el2; /* Virtual SError Exception Syndrome Register */ }; /* @@ -385,6 +386,7 @@ int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr); int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr); +int kvm_vcpu_ioctl_sei(struct kvm_vcpu *vcpu, u64 *syndrome); static inline void __cpu_init_stage2(void) { diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index 32964c7..3af6907 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -125,6 +125,9 @@ #define REG_PSTATE_PAN_IMM sys_reg(0, 0, 4, 0, 4) #define REG_PSTATE_UAO_IMM sys_reg(0, 0, 4, 0, 3) +/* virtual SError exception syndrome register in armv8.2 */ +#define REG_VSESR_EL2 sys_reg(3, 4, 5, 2, 3) + #define SET_PSTATE_PAN(x) __emit_inst(0xd5000000 | REG_PSTATE_PAN_IMM | \ (!!x)<<8 | 0x1f) #define SET_PSTATE_UAO(x) __emit_inst(0xd5000000 | REG_PSTATE_UAO_IMM | \ diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index b37446a..21c20b0 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -277,6 +277,20 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, return -EINVAL; } +int kvm_vcpu_ioctl_sei(struct kvm_vcpu *vcpu, u64 *syndrome) +{ + u64 reg = *syndrome; + + if (cpus_have_const_cap(ARM64_HAS_RAS_EXTN) && reg) + /* set vsesr_el2[24:0] with value that user space specified */ + kvm_vcpu_set_vsesr(vcpu, reg & VSESR_ELx_IDS_ISS_MASK); + + /* inject virtual system Error or asynchronous abort */ + kvm_inject_vabt(vcpu); + + return 0; +} + int __attribute_const__ kvm_target_cpu(void) { unsigned long implementor = read_cpuid_implementor(); diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index c89d83a..23c02c2 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -180,7 +180,11 @@ static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu) static int kvm_handle_guest_sei(struct kvm_vcpu *vcpu, struct kvm_run *run) { - unsigned long fault_ipa = kvm_vcpu_get_fault_ipa(vcpu); + unsigned long hva, fault_ipa = kvm_vcpu_get_fault_ipa(vcpu); + struct kvm_memory_slot *memslot; + int hsr, ret = 1; + bool writable; + gfn_t gfn; if (handle_guest_sei((unsigned long)fault_ipa, kvm_vcpu_get_hsr(vcpu))) { @@ -190,9 +194,20 @@ static int kvm_handle_guest_sei(struct kvm_vcpu *vcpu, struct kvm_run *run) (unsigned long)kvm_vcpu_get_hsr(vcpu)); kvm_inject_vabt(vcpu); + } else { + hsr = kvm_vcpu_get_hsr(vcpu); + + gfn = fault_ipa >> PAGE_SHIFT; + memslot = gfn_to_memslot(vcpu->kvm, gfn); + hva = gfn_to_hva_memslot_prot(memslot, gfn, &writable); + + run->exit_reason = KVM_EXIT_SERROR_INTR; + run->serror_intr.syndrome_info = hsr; + run->serror_intr.address = hva; + ret = 0; } - return 0; + return ret; } /* @@ -218,8 +233,7 @@ int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run, *vcpu_pc(vcpu) -= adj; } - kvm_handle_guest_sei(vcpu, run); - return 1; + return kvm_handle_guest_sei(vcpu, run); } exception_index = ARM_EXCEPTION_CODE(exception_index); @@ -228,8 +242,7 @@ int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run, case ARM_EXCEPTION_IRQ: return 1; case ARM_EXCEPTION_EL1_SERROR: - kvm_handle_guest_sei(vcpu, run); - return 1; + return kvm_handle_guest_sei(vcpu, run); case ARM_EXCEPTION_TRAP: /* * See ARM ARM B1.14.1: "Hyp traps on instructions diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index aede165..6d17c97 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -67,6 +67,13 @@ static hyp_alternate_select(__activate_traps_arch, __activate_traps_nvhe, __activate_traps_vhe, ARM64_HAS_VIRT_HOST_EXTN); +static void __hyp_text __sysreg_set_vsesr(struct kvm_vcpu *vcpu) +{ + if (cpus_have_const_cap(ARM64_HAS_RAS_EXTN) && + (vcpu->arch.hcr_el2 & HCR_VSE)) + write_sysreg_s(vcpu->arch.fault.vsesr_el2, REG_VSESR_EL2); +} + static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu) { u64 val; @@ -86,6 +93,13 @@ static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu) isb(); } write_sysreg(val, hcr_el2); + + /* + * If the virtual SError interrupt is taken to EL1 using AArch64, + * then VSESR_EL2 provides the syndrome value reported in ESR_EL1. + */ + __sysreg_set_vsesr(vcpu); + /* Trap on AArch32 cp15 c15 accesses (EL1 or EL0) */ write_sysreg(1 << 15, hstr_el2); /* diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 27fe556..ab91fe3 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -205,6 +205,7 @@ struct kvm_hyperv_exit { #define KVM_EXIT_S390_STSI 25 #define KVM_EXIT_IOAPIC_EOI 26 #define KVM_EXIT_HYPERV 27 +#define KVM_EXIT_SERROR_INTR 28 /* For KVM_EXIT_INTERNAL_ERROR */ /* Emulate instruction failed. */ @@ -360,6 +361,11 @@ struct kvm_run { struct { __u8 vector; } eoi; + /* KVM_EXIT_SERROR_INTR */ + struct { + __u32 syndrome_info; + __u64 address; + } serror_intr; /* KVM_EXIT_HYPERV */ struct kvm_hyperv_exit hyperv; /* Fix the size of the union. */ @@ -1301,6 +1307,8 @@ struct kvm_s390_ucas_mapping { #define KVM_S390_GET_IRQ_STATE _IOW(KVMIO, 0xb6, struct kvm_s390_irq_state) /* Available with KVM_CAP_X86_SMM */ #define KVM_SMI _IO(KVMIO, 0xb7) +/* Available with KVM_EXIT_SERROR_INTR */ +#define KVM_ARM_SEI _IO(KVMIO, 0xb8) #define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0) #define KVM_DEV_ASSIGN_PCI_2_3 (1 << 1) -- 2.10.1 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html