Currently, the kvm_psci_call() returns 'true' or 'false' based on whether the PSCI function call was handled successfully or not. This does not help us emulate system-level PSCI functions where the actual emulation work will be done by user space (QEMU or KVMTOOL). Examples of such system-level PSCI functions are: PSCI v0.2 SYSTEM_OFF and SYSTEM_RESET.
This patch updates kvm_psci_call() to return three types of values: 1) > 0 (success) 2) = 0 (success but exit to user space) 3) < 0 (errors)
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org Reviewed-by: Christoffer Dall christoffer.dall@linaro.org Acked-by: Marc Zyngier marc.zyngier@arm.com --- arch/arm/include/asm/kvm_psci.h | 2 +- arch/arm/kvm/handle_exit.c | 10 +++++++--- arch/arm/kvm/psci.c | 28 ++++++++++++++++------------ arch/arm64/include/asm/kvm_psci.h | 2 +- arch/arm64/kvm/handle_exit.c | 10 +++++++--- 5 files changed, 32 insertions(+), 20 deletions(-)
diff --git a/arch/arm/include/asm/kvm_psci.h b/arch/arm/include/asm/kvm_psci.h index 4c0e3e1..6bda945 100644 --- a/arch/arm/include/asm/kvm_psci.h +++ b/arch/arm/include/asm/kvm_psci.h @@ -22,6 +22,6 @@ #define KVM_ARM_PSCI_0_2 2
int kvm_psci_version(struct kvm_vcpu *vcpu); -bool kvm_psci_call(struct kvm_vcpu *vcpu); +int kvm_psci_call(struct kvm_vcpu *vcpu);
#endif /* __ARM_KVM_PSCI_H__ */ diff --git a/arch/arm/kvm/handle_exit.c b/arch/arm/kvm/handle_exit.c index 0de91fc..4c979d4 100644 --- a/arch/arm/kvm/handle_exit.c +++ b/arch/arm/kvm/handle_exit.c @@ -38,14 +38,18 @@ static int handle_svc_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run)
static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run) { + int ret; + trace_kvm_hvc(*vcpu_pc(vcpu), *vcpu_reg(vcpu, 0), kvm_vcpu_hvc_get_imm(vcpu));
- if (kvm_psci_call(vcpu)) + ret = kvm_psci_call(vcpu); + if (ret < 0) { + kvm_inject_undefined(vcpu); return 1; + }
- kvm_inject_undefined(vcpu); - return 1; + return ret; }
static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run) diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index 8c42596c..14e6fa6 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -93,7 +93,7 @@ int kvm_psci_version(struct kvm_vcpu *vcpu) return KVM_ARM_PSCI_0_1; }
-static bool kvm_psci_0_2_call(struct kvm_vcpu *vcpu) +static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu) { unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); unsigned long val; @@ -128,14 +128,14 @@ static bool kvm_psci_0_2_call(struct kvm_vcpu *vcpu) val = PSCI_RET_NOT_SUPPORTED; break; default: - return false; + return -EINVAL; }
*vcpu_reg(vcpu, 0) = val; - return true; + return 1; }
-static bool kvm_psci_0_1_call(struct kvm_vcpu *vcpu) +static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu) { unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); unsigned long val; @@ -153,11 +153,11 @@ static bool kvm_psci_0_1_call(struct kvm_vcpu *vcpu) val = PSCI_RET_NOT_SUPPORTED; break; default: - return false; + return -EINVAL; }
*vcpu_reg(vcpu, 0) = val; - return true; + return 1; }
/** @@ -165,12 +165,16 @@ static bool kvm_psci_0_1_call(struct kvm_vcpu *vcpu) * @vcpu: Pointer to the VCPU struct * * Handle PSCI calls from guests through traps from HVC instructions. - * The calling convention is similar to SMC calls to the secure world where - * the function number is placed in r0 and this function returns true if the - * function number specified in r0 is withing the PSCI range, and false - * otherwise. + * The calling convention is similar to SMC calls to the secure world + * where the function number is placed in r0. + * + * This function returns: > 0 (success), 0 (success but exit to user + * space), and < 0 (errors) + * + * Errors: + * -EINVAL: Unrecognized PSCI function */ -bool kvm_psci_call(struct kvm_vcpu *vcpu) +int kvm_psci_call(struct kvm_vcpu *vcpu) { switch (kvm_psci_version(vcpu)) { case KVM_ARM_PSCI_0_2: @@ -178,6 +182,6 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu) case KVM_ARM_PSCI_0_1: return kvm_psci_0_1_call(vcpu); default: - return false; + return -EINVAL; }; } diff --git a/arch/arm64/include/asm/kvm_psci.h b/arch/arm64/include/asm/kvm_psci.h index e25c658..bc39e55 100644 --- a/arch/arm64/include/asm/kvm_psci.h +++ b/arch/arm64/include/asm/kvm_psci.h @@ -22,6 +22,6 @@ #define KVM_ARM_PSCI_0_2 2
int kvm_psci_version(struct kvm_vcpu *vcpu); -bool kvm_psci_call(struct kvm_vcpu *vcpu); +int kvm_psci_call(struct kvm_vcpu *vcpu);
#endif /* __ARM64_KVM_PSCI_H__ */ diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 7bc41ea..182415e 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -30,11 +30,15 @@ typedef int (*exit_handle_fn)(struct kvm_vcpu *, struct kvm_run *);
static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run) { - if (kvm_psci_call(vcpu)) + int ret; + + ret = kvm_psci_call(vcpu); + if (ret < 0) { + kvm_inject_undefined(vcpu); return 1; + }
- kvm_inject_undefined(vcpu); - return 1; + return ret; }
static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run)