From 512865d83fd9685a4d5aab26f898737b57d3187e Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Mon, 21 Feb 2022 15:35:22 +0000 Subject: [PATCH 1/4] KVM: arm64: Bump guest PSCI version to 1.1 Expose PSCI version v1.1 to the guest by default. The only difference for now is that an updated version number is reported by PSCI_VERSION. Cc: Marc Zyngier Cc: James Morse Cc: Alexandru Elisei Cc: Suzuki K Poulose Signed-off-by: Will Deacon Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220221153524.15397-2-will@kernel.org --- arch/arm64/kvm/psci.c | 12 +++++++++--- include/kvm/arm_psci.h | 3 ++- 2 files changed, 11 insertions(+), 4 deletions(-) diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c index 3eae32876897..70d07477e712 100644 --- a/arch/arm64/kvm/psci.c +++ b/arch/arm64/kvm/psci.c @@ -305,16 +305,19 @@ out: return ret; } -static int kvm_psci_1_0_call(struct kvm_vcpu *vcpu) +static int kvm_psci_1_x_call(struct kvm_vcpu *vcpu, u32 minor) { u32 psci_fn = smccc_get_function(vcpu); u32 feature; unsigned long val; int ret = 1; + if (minor > 1) + return -EINVAL; + switch(psci_fn) { case PSCI_0_2_FN_PSCI_VERSION: - val = KVM_ARM_PSCI_1_0; + val = minor == 0 ? KVM_ARM_PSCI_1_0 : KVM_ARM_PSCI_1_1; break; case PSCI_1_0_FN_PSCI_FEATURES: feature = smccc_get_arg1(vcpu); @@ -393,8 +396,10 @@ static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu) int kvm_psci_call(struct kvm_vcpu *vcpu) { switch (kvm_psci_version(vcpu, vcpu->kvm)) { + case KVM_ARM_PSCI_1_1: + return kvm_psci_1_x_call(vcpu, 1); case KVM_ARM_PSCI_1_0: - return kvm_psci_1_0_call(vcpu); + return kvm_psci_1_x_call(vcpu, 0); case KVM_ARM_PSCI_0_2: return kvm_psci_0_2_call(vcpu); case KVM_ARM_PSCI_0_1: @@ -511,6 +516,7 @@ int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) return 0; case KVM_ARM_PSCI_0_2: case KVM_ARM_PSCI_1_0: + case KVM_ARM_PSCI_1_1: if (!wants_02) return -EINVAL; vcpu->kvm->arch.psci_version = val; diff --git a/include/kvm/arm_psci.h b/include/kvm/arm_psci.h index 5b58bd2fe088..4a1003323a0c 100644 --- a/include/kvm/arm_psci.h +++ b/include/kvm/arm_psci.h @@ -13,8 +13,9 @@ #define KVM_ARM_PSCI_0_1 PSCI_VERSION(0, 1) #define KVM_ARM_PSCI_0_2 PSCI_VERSION(0, 2) #define KVM_ARM_PSCI_1_0 PSCI_VERSION(1, 0) +#define KVM_ARM_PSCI_1_1 PSCI_VERSION(1, 1) -#define KVM_ARM_PSCI_LATEST KVM_ARM_PSCI_1_0 +#define KVM_ARM_PSCI_LATEST KVM_ARM_PSCI_1_1 /* * We need the KVM pointer independently from the vcpu as we can call From d43583b890e7cb0078d13d056753a56602b92406 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Mon, 21 Feb 2022 15:35:23 +0000 Subject: [PATCH 2/4] KVM: arm64: Expose PSCI SYSTEM_RESET2 call to the guest PSCI v1.1 introduces the optional SYSTEM_RESET2 call, which allows the caller to provide a vendor-specific "reset type" and "cookie" to request a particular form of reset or shutdown. Expose this call to the guest and handle it in the same way as PSCI SYSTEM_RESET, along with some basic range checking on the type argument. Cc: Marc Zyngier Cc: James Morse Cc: Alexandru Elisei Cc: Suzuki K Poulose Signed-off-by: Will Deacon Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220221153524.15397-3-will@kernel.org --- arch/arm64/kvm/psci.c | 33 +++++++++++++++++++++++++++++---- include/uapi/linux/psci.h | 4 ++++ 2 files changed, 33 insertions(+), 4 deletions(-) diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c index 70d07477e712..30fcc5a99483 100644 --- a/arch/arm64/kvm/psci.c +++ b/arch/arm64/kvm/psci.c @@ -308,7 +308,7 @@ out: static int kvm_psci_1_x_call(struct kvm_vcpu *vcpu, u32 minor) { u32 psci_fn = smccc_get_function(vcpu); - u32 feature; + u32 arg; unsigned long val; int ret = 1; @@ -320,12 +320,12 @@ static int kvm_psci_1_x_call(struct kvm_vcpu *vcpu, u32 minor) val = minor == 0 ? KVM_ARM_PSCI_1_0 : KVM_ARM_PSCI_1_1; break; case PSCI_1_0_FN_PSCI_FEATURES: - feature = smccc_get_arg1(vcpu); - val = kvm_psci_check_allowed_function(vcpu, feature); + arg = smccc_get_arg1(vcpu); + val = kvm_psci_check_allowed_function(vcpu, arg); if (val) break; - switch(feature) { + switch(arg) { case PSCI_0_2_FN_PSCI_VERSION: case PSCI_0_2_FN_CPU_SUSPEND: case PSCI_0_2_FN64_CPU_SUSPEND: @@ -341,11 +341,36 @@ static int kvm_psci_1_x_call(struct kvm_vcpu *vcpu, u32 minor) case ARM_SMCCC_VERSION_FUNC_ID: val = 0; break; + case PSCI_1_1_FN_SYSTEM_RESET2: + case PSCI_1_1_FN64_SYSTEM_RESET2: + if (minor >= 1) { + val = 0; + break; + } + fallthrough; default: val = PSCI_RET_NOT_SUPPORTED; break; } break; + case PSCI_1_1_FN_SYSTEM_RESET2: + kvm_psci_narrow_to_32bit(vcpu); + fallthrough; + case PSCI_1_1_FN64_SYSTEM_RESET2: + if (minor >= 1) { + arg = smccc_get_arg1(vcpu); + + if (arg > PSCI_1_1_RESET_TYPE_SYSTEM_WARM_RESET && + arg < PSCI_1_1_RESET_TYPE_VENDOR_START) { + val = PSCI_RET_INVALID_PARAMS; + } else { + kvm_psci_system_reset(vcpu); + val = PSCI_RET_INTERNAL_FAILURE; + ret = 0; + } + break; + }; + fallthrough; default: return kvm_psci_0_2_call(vcpu); } diff --git a/include/uapi/linux/psci.h b/include/uapi/linux/psci.h index 2fcad1dd0b0e..2bf93c0d6354 100644 --- a/include/uapi/linux/psci.h +++ b/include/uapi/linux/psci.h @@ -82,6 +82,10 @@ #define PSCI_0_2_TOS_UP_NO_MIGRATE 1 #define PSCI_0_2_TOS_MP 2 +/* PSCI v1.1 reset type encoding for SYSTEM_RESET2 */ +#define PSCI_1_1_RESET_TYPE_SYSTEM_WARM_RESET 0 +#define PSCI_1_1_RESET_TYPE_VENDOR_START 0x80000000U + /* PSCI version decoding (independent of PSCI version) */ #define PSCI_VERSION_MAJOR_SHIFT 16 #define PSCI_VERSION_MINOR_MASK \ From 34739fd95fab3a5efb0422e4f012b685e33598dc Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Mon, 21 Feb 2022 15:35:24 +0000 Subject: [PATCH 3/4] KVM: arm64: Indicate SYSTEM_RESET2 in kvm_run::system_event flags field When handling reset and power-off PSCI calls from the guest, we initialise X0 to PSCI_RET_INTERNAL_FAILURE in case the VMM tries to re-run the vCPU after issuing the call. Unfortunately, this also means that the VMM cannot see which PSCI call was issued and therefore cannot distinguish between PSCI SYSTEM_RESET and SYSTEM_RESET2 calls, which is necessary in order to determine the validity of the "reset_type" in X1. Allocate bit 0 of the previously unused 'flags' field of the system_event structure so that we can indicate the PSCI call used to initiate the reset. Cc: Marc Zyngier Cc: James Morse Cc: Alexandru Elisei Cc: Suzuki K Poulose Signed-off-by: Will Deacon Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220221153524.15397-4-will@kernel.org --- Documentation/virt/kvm/api.rst | 5 +++++ arch/arm64/include/uapi/asm/kvm.h | 7 +++++++ arch/arm64/kvm/psci.c | 15 +++++++++++---- 3 files changed, 23 insertions(+), 4 deletions(-) diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index a4267104db50..8305ac9747b6 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -5939,6 +5939,11 @@ Valid values for 'type' are: to ignore the request, or to gather VM memory core dump and/or reset/shutdown of the VM. +Valid flags are: + + - KVM_SYSTEM_EVENT_RESET_FLAG_PSCI_RESET2 (arm64 only) -- the guest issued + a SYSTEM_RESET2 call according to v1.1 of the PSCI specification. + :: /* KVM_EXIT_IOAPIC_EOI */ diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index b3edde68bc3e..06bc08fdf8ea 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -413,6 +413,13 @@ struct kvm_arm_copy_mte_tags { #define KVM_PSCI_RET_INVAL PSCI_RET_INVALID_PARAMS #define KVM_PSCI_RET_DENIED PSCI_RET_DENIED +/* arm64-specific kvm_run::system_event flags */ +/* + * Reset caused by a PSCI v1.1 SYSTEM_RESET2 call. + * Valid only when the system event has a type of KVM_SYSTEM_EVENT_RESET. + */ +#define KVM_SYSTEM_EVENT_RESET_FLAG_PSCI_RESET2 (1ULL << 0) + #endif #endif /* __ARM_KVM_H__ */ diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c index 30fcc5a99483..ecb4b74cb12a 100644 --- a/arch/arm64/kvm/psci.c +++ b/arch/arm64/kvm/psci.c @@ -162,7 +162,7 @@ static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu) return PSCI_0_2_AFFINITY_LEVEL_OFF; } -static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type) +static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type, u64 flags) { unsigned long i; struct kvm_vcpu *tmp; @@ -182,17 +182,24 @@ static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type) memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event)); vcpu->run->system_event.type = type; + vcpu->run->system_event.flags = flags; vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; } static void kvm_psci_system_off(struct kvm_vcpu *vcpu) { - kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_SHUTDOWN); + kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_SHUTDOWN, 0); } static void kvm_psci_system_reset(struct kvm_vcpu *vcpu) { - kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_RESET); + kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_RESET, 0); +} + +static void kvm_psci_system_reset2(struct kvm_vcpu *vcpu) +{ + kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_RESET, + KVM_SYSTEM_EVENT_RESET_FLAG_PSCI_RESET2); } static void kvm_psci_narrow_to_32bit(struct kvm_vcpu *vcpu) @@ -364,7 +371,7 @@ static int kvm_psci_1_x_call(struct kvm_vcpu *vcpu, u32 minor) arg < PSCI_1_1_RESET_TYPE_VENDOR_START) { val = PSCI_RET_INVALID_PARAMS; } else { - kvm_psci_system_reset(vcpu); + kvm_psci_system_reset2(vcpu); val = PSCI_RET_INTERNAL_FAILURE; ret = 0; } From ae82047e97a3014d843d4fb931922982ef625e54 Mon Sep 17 00:00:00 2001 From: Changcheng Deng Date: Wed, 23 Feb 2022 09:27:50 +0000 Subject: [PATCH 4/4] KVM: arm64: Remove unneeded semicolons Fix the following coccicheck review: ./arch/arm64/kvm/psci.c: 379: 3-4: Unneeded semicolon Reported-by: Zeal Robot Signed-off-by: Changcheng Deng [maz: squashed another instance of the same issue in the patch] Signed-off-by: Marc Zyngier Acked-by: Will Deacon Link: https://lore.kernel.org/r/20220223092750.1934130-1-deng.changcheng@zte.com.cn Link: https://lore.kernel.org/r/20220225122922.GA19390@willie-the-truck --- arch/arm64/kvm/psci.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c index ecb4b74cb12a..0d48d1e7291d 100644 --- a/arch/arm64/kvm/psci.c +++ b/arch/arm64/kvm/psci.c @@ -376,7 +376,7 @@ static int kvm_psci_1_x_call(struct kvm_vcpu *vcpu, u32 minor) ret = 0; } break; - }; + } fallthrough; default: return kvm_psci_0_2_call(vcpu); @@ -438,7 +438,7 @@ int kvm_psci_call(struct kvm_vcpu *vcpu) return kvm_psci_0_1_call(vcpu); default: return -EINVAL; - }; + } } int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu)