Currently, KVM ARM/ARM64 only provides in-kernel emulation of Power State and Coordination Interface (PSCI) v0.1.
This patchset aims at providing newer PSCI v0.2 for KVM ARM/ARM64 VCPUs such that it does not break current KVM ARM/ARM64 ABI. Also, the patchset provides emulation of only few PSCI v0.2 functions such as PSCI_VERSION, CPU_ON, and CPU_OFF. Emulation of other PSCI v0.2 functions will be added later.
The user space tools (i.e. QEMU or KVMTOOL) will have to explicitly enable KVM_ARM_VCPU_PSCI_0_2 feature using KVM_ARM_VCPU_INIT ioctl for providing PSCI v0.2 to VCPUs.
Changlog:
V2: - Don't rename PSCI return values KVM_PSCI_RET_NI and KVM_PSCI_RET_INVAL - Added kvm_psci_version() to get PSCI version available to VCPU - Fixed grammer in Documentation/virtual/kvm/api.txt
V1: - Initial RFC PATCH
Anup Patel (3): KVM: Add capability to advertise PSCI v0.2 support ARM/ARM64: KVM: Add support for PSCI v0.2 emulation KVM: Documentation: Add info regarding KVM_ARM_VCPU_PSCI_0_2 feature
Documentation/virtual/kvm/api.txt | 2 + arch/arm/include/asm/kvm_host.h | 2 +- arch/arm/include/asm/kvm_psci.h | 4 ++ arch/arm/include/uapi/asm/kvm.h | 35 ++++++++++++++- arch/arm/kvm/arm.c | 1 + arch/arm/kvm/psci.c | 85 +++++++++++++++++++++++++++++++------ arch/arm64/include/asm/kvm_host.h | 2 +- arch/arm64/include/asm/kvm_psci.h | 4 ++ arch/arm64/include/uapi/asm/kvm.h | 35 ++++++++++++++- include/uapi/linux/kvm.h | 1 + 10 files changed, 155 insertions(+), 16 deletions(-)
User space (i.e. QEMU or KVMTOOL) should be able to check whether KVM ARM/ARM64 supports in-kernel PSCI v0.2 emulation. For this purpose, we define KVM_CAP_ARM_PSCI_0_2 in KVM user space interface header.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org --- include/uapi/linux/kvm.h | 1 + 1 file changed, 1 insertion(+)
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 902f124..d64349e 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -674,6 +674,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_ARM_EL1_32BIT 93 #define KVM_CAP_SPAPR_MULTITCE 94 #define KVM_CAP_EXT_EMUL_CPUID 95 +#define KVM_CAP_ARM_PSCI_0_2 96
#ifdef KVM_CAP_IRQ_ROUTING
On Thu, Jan 30, 2014 at 04:11:17PM +0530, Anup Patel wrote:
User space (i.e. QEMU or KVMTOOL) should be able to check whether KVM ARM/ARM64 supports in-kernel PSCI v0.2 emulation. For this purpose, we define KVM_CAP_ARM_PSCI_0_2 in KVM user space interface header.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org
include/uapi/linux/kvm.h | 1 + 1 file changed, 1 insertion(+)
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 902f124..d64349e 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -674,6 +674,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_ARM_EL1_32BIT 93 #define KVM_CAP_SPAPR_MULTITCE 94 #define KVM_CAP_EXT_EMUL_CPUID 95 +#define KVM_CAP_ARM_PSCI_0_2 96 #ifdef KVM_CAP_IRQ_ROUTING -- 1.7.9.5
Acked-by: Christoffer Dall christoffer.dall@linaro.org
On Thu, Jan 30, 2014 at 10:41:17AM +0000, Anup Patel wrote:
User space (i.e. QEMU or KVMTOOL) should be able to check whether KVM ARM/ARM64 supports in-kernel PSCI v0.2 emulation. For this purpose, we define KVM_CAP_ARM_PSCI_0_2 in KVM user space interface header.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org
include/uapi/linux/kvm.h | 1 + 1 file changed, 1 insertion(+)
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 902f124..d64349e 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -674,6 +674,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_ARM_EL1_32BIT 93 #define KVM_CAP_SPAPR_MULTITCE 94 #define KVM_CAP_EXT_EMUL_CPUID 95 +#define KVM_CAP_ARM_PSCI_0_2 96
To reiterate the point I made on patch 2, this does not do what it says on the tin, and does not make sense without mandatory PSCI 0.2 functionality being present, as no software can derive any value from this flag until such functionality is implemented.
Thanks, Mark.
On Mon, Feb 3, 2014 at 5:18 PM, Mark Rutland mark.rutland@arm.com wrote:
On Thu, Jan 30, 2014 at 10:41:17AM +0000, Anup Patel wrote:
User space (i.e. QEMU or KVMTOOL) should be able to check whether KVM ARM/ARM64 supports in-kernel PSCI v0.2 emulation. For this purpose, we define KVM_CAP_ARM_PSCI_0_2 in KVM user space interface header.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org
include/uapi/linux/kvm.h | 1 + 1 file changed, 1 insertion(+)
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 902f124..d64349e 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -674,6 +674,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_ARM_EL1_32BIT 93 #define KVM_CAP_SPAPR_MULTITCE 94 #define KVM_CAP_EXT_EMUL_CPUID 95 +#define KVM_CAP_ARM_PSCI_0_2 96
To reiterate the point I made on patch 2, this does not do what it says on the tin, and does not make sense without mandatory PSCI 0.2 functionality being present, as no software can derive any value from this flag until such functionality is implemented.
I handle this situation I would suggest to not advertise PSCI v0.2 capability to user space till all mandatory PSCI v0.2 functions are implemented. We will also need to defer the change in arch/arm/kvm/arm.c done by patch 2.
Regards, Anup
Thanks, Mark. _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm
On Mon, Feb 03, 2014 at 12:09:22PM +0000, Anup Patel wrote:
On Mon, Feb 3, 2014 at 5:18 PM, Mark Rutland mark.rutland@arm.com wrote:
On Thu, Jan 30, 2014 at 10:41:17AM +0000, Anup Patel wrote:
User space (i.e. QEMU or KVMTOOL) should be able to check whether KVM ARM/ARM64 supports in-kernel PSCI v0.2 emulation. For this purpose, we define KVM_CAP_ARM_PSCI_0_2 in KVM user space interface header.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org
include/uapi/linux/kvm.h | 1 + 1 file changed, 1 insertion(+)
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 902f124..d64349e 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -674,6 +674,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_ARM_EL1_32BIT 93 #define KVM_CAP_SPAPR_MULTITCE 94 #define KVM_CAP_EXT_EMUL_CPUID 95 +#define KVM_CAP_ARM_PSCI_0_2 96
To reiterate the point I made on patch 2, this does not do what it says on the tin, and does not make sense without mandatory PSCI 0.2 functionality being present, as no software can derive any value from this flag until such functionality is implemented.
I handle this situation I would suggest to not advertise PSCI v0.2 capability to user space till all mandatory PSCI v0.2 functions are implemented. We will also need to defer the change in arch/arm/kvm/arm.c done by patch 2.
Until all the mandatory PSCI 0.2 functions are implemented it should not be possible to ask the kernel for a partial implementation, yes.
Thanks, Mark.
Currently, the in-kernel PSCI emulation provides PSCI v0.1 interface to VCPUs. This patch extends current in-kernel PSCI emulation to provide PSCI v0.2 interface to VCPUs.
By default, ARM/ARM64 KVM will always provide PSCI v0.1 interface for keeping the ABI backward-compatible.
To select PSCI v0.2 interface for VCPUs, the user space (i.e. QEMU or KVMTOOL) will have to set KVM_ARM_VCPU_PSCI_0_2 feature when doing VCPU init using KVM_ARM_VCPU_INIT ioctl.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org --- arch/arm/include/asm/kvm_host.h | 2 +- arch/arm/include/asm/kvm_psci.h | 4 ++ arch/arm/include/uapi/asm/kvm.h | 35 ++++++++++++++- arch/arm/kvm/arm.c | 1 + arch/arm/kvm/psci.c | 85 +++++++++++++++++++++++++++++++------ arch/arm64/include/asm/kvm_host.h | 2 +- arch/arm64/include/asm/kvm_psci.h | 4 ++ arch/arm64/include/uapi/asm/kvm.h | 35 ++++++++++++++- 8 files changed, 152 insertions(+), 16 deletions(-)
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index bce6d32..dc4e3ed 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -36,7 +36,7 @@ #define KVM_COALESCED_MMIO_PAGE_OFFSET 1 #define KVM_HAVE_ONE_REG
-#define KVM_VCPU_MAX_FEATURES 1 +#define KVM_VCPU_MAX_FEATURES 2
#include <kvm/arm_vgic.h>
diff --git a/arch/arm/include/asm/kvm_psci.h b/arch/arm/include/asm/kvm_psci.h index 9a83d98..4c0e3e1 100644 --- a/arch/arm/include/asm/kvm_psci.h +++ b/arch/arm/include/asm/kvm_psci.h @@ -18,6 +18,10 @@ #ifndef __ARM_KVM_PSCI_H__ #define __ARM_KVM_PSCI_H__
+#define KVM_ARM_PSCI_0_1 1 +#define KVM_ARM_PSCI_0_2 2 + +int kvm_psci_version(struct kvm_vcpu *vcpu); bool kvm_psci_call(struct kvm_vcpu *vcpu);
#endif /* __ARM_KVM_PSCI_H__ */ diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h index c498b60..bf860e2 100644 --- a/arch/arm/include/uapi/asm/kvm.h +++ b/arch/arm/include/uapi/asm/kvm.h @@ -83,6 +83,7 @@ struct kvm_regs { #define KVM_VGIC_V2_CPU_SIZE 0x2000
#define KVM_ARM_VCPU_POWER_OFF 0 /* CPU is started in OFF state */ +#define KVM_ARM_VCPU_PSCI_0_2 1 /* CPU uses PSCI v0.2 */
struct kvm_vcpu_init { __u32 target; @@ -164,7 +165,7 @@ struct kvm_arch_memory_slot { /* Highest supported SPI, from VGIC_NR_IRQS */ #define KVM_ARM_IRQ_GIC_MAX 127
-/* PSCI interface */ +/* PSCI v0.1 interface */ #define KVM_PSCI_FN_BASE 0x95c1ba5e #define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n))
@@ -173,9 +174,41 @@ struct kvm_arch_memory_slot { #define KVM_PSCI_FN_CPU_ON KVM_PSCI_FN(2) #define KVM_PSCI_FN_MIGRATE KVM_PSCI_FN(3)
+/* PSCI v0.2 interface */ +#define KVM_PSCI_0_2_FN_BASE 0x84000000 +#define KVM_PSCI_0_2_FN(n) (KVM_PSCI_0_2_FN_BASE + (n)) +#define KVM_PSCI_0_2_FN64_BASE 0xC4000000 +#define KVM_PSCI_0_2_FN64(n) (KVM_PSCI_0_2_FN64_BASE + (n)) + +#define KVM_PSCI_0_2_FN_PSCI_VERSION KVM_PSCI_0_2_FN(0) +#define KVM_PSCI_0_2_FN_CPU_SUSPEND KVM_PSCI_0_2_FN(1) +#define KVM_PSCI_0_2_FN_CPU_OFF KVM_PSCI_0_2_FN(2) +#define KVM_PSCI_0_2_FN_CPU_ON KVM_PSCI_0_2_FN(3) +#define KVM_PSCI_0_2_FN_AFFINITY_INFO KVM_PSCI_0_2_FN(4) +#define KVM_PSCI_0_2_FN_MIGRATE KVM_PSCI_0_2_FN(5) +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \ + KVM_PSCI_0_2_FN(6) +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \ + KVM_PSCI_0_2_FN(7) +#define KVM_PSCI_0_2_FN_SYSTEM_OFF KVM_PSCI_0_2_FN(8) +#define KVM_PSCI_0_2_FN_SYSTEM_RESET KVM_PSCI_0_2_FN(9) + +#define KVM_PSCI_0_2_FN64_CPU_SUSPEND KVM_PSCI_0_2_FN64(1) +#define KVM_PSCI_0_2_FN64_CPU_ON KVM_PSCI_0_2_FN64(3) +#define KVM_PSCI_0_2_FN64_AFFINITY_INFO KVM_PSCI_0_2_FN64(4) +#define KVM_PSCI_0_2_FN64_MIGRATE KVM_PSCI_0_2_FN64(5) +#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \ + KVM_PSCI_0_2_FN64(7) + +/* PSCI return values */ #define KVM_PSCI_RET_SUCCESS 0 #define KVM_PSCI_RET_NI ((unsigned long)-1) #define KVM_PSCI_RET_INVAL ((unsigned long)-2) #define KVM_PSCI_RET_DENIED ((unsigned long)-3) +#define KVM_PSCI_RET_ALREADY_ON ((unsigned long)-4) +#define KVM_PSCI_RET_ON_PENDING ((unsigned long)-5) +#define KVM_PSCI_RET_INTERNAL_FAILURE ((unsigned long)-6) +#define KVM_PSCI_RET_NOT_PRESENT ((unsigned long)-7) +#define KVM_PSCI_RET_DISABLED ((unsigned long)-8)
#endif /* __ARM_KVM_H__ */ diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 151eb91..e508125 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -193,6 +193,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: case KVM_CAP_ONE_REG: case KVM_CAP_ARM_PSCI: + case KVM_CAP_ARM_PSCI_0_2: r = 1; break; case KVM_CAP_COALESCED_MMIO: diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index 448f60e..7fdc881 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -85,17 +85,57 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) return KVM_PSCI_RET_SUCCESS; }
-/** - * kvm_psci_call - handle PSCI call if r0 value is in range - * @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. - */ -bool kvm_psci_call(struct kvm_vcpu *vcpu) +int kvm_psci_version(struct kvm_vcpu *vcpu) +{ + if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features)) + return KVM_ARM_PSCI_0_2; + + return KVM_ARM_PSCI_0_1; +} + +static bool kvm_psci_0_2_call(struct kvm_vcpu *vcpu) +{ + unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); + unsigned long val; + + switch (psci_fn) { + case KVM_PSCI_0_2_FN_PSCI_VERSION: + /* + * Bits[31:16] = Major Version = 0 + * Bits[15:0] = Minor Version = 2 + */ + val = 2; + break; + case KVM_PSCI_0_2_FN_CPU_OFF: + kvm_psci_vcpu_off(vcpu); + val = KVM_PSCI_RET_SUCCESS; + break; + case KVM_PSCI_0_2_FN_CPU_ON: + case KVM_PSCI_0_2_FN64_CPU_ON: + val = kvm_psci_vcpu_on(vcpu); + break; + case KVM_PSCI_0_2_FN_CPU_SUSPEND: + case KVM_PSCI_0_2_FN_AFFINITY_INFO: + case KVM_PSCI_0_2_FN_MIGRATE: + case KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE: + case KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU: + case KVM_PSCI_0_2_FN_SYSTEM_OFF: + case KVM_PSCI_0_2_FN_SYSTEM_RESET: + case KVM_PSCI_0_2_FN64_CPU_SUSPEND: + case KVM_PSCI_0_2_FN64_AFFINITY_INFO: + case KVM_PSCI_0_2_FN64_MIGRATE: + case KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU: + val = KVM_PSCI_RET_NI; + break; + default: + return false; + } + + *vcpu_reg(vcpu, 0) = val; + return true; +} + +static bool kvm_psci_0_1_call(struct kvm_vcpu *vcpu) { unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); unsigned long val; @@ -112,7 +152,6 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu) case KVM_PSCI_FN_MIGRATE: val = KVM_PSCI_RET_NI; break; - default: return false; } @@ -120,3 +159,25 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu) *vcpu_reg(vcpu, 0) = val; return true; } + +/** + * kvm_psci_call - handle PSCI call if r0 value is in range + * @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. + */ +bool kvm_psci_call(struct kvm_vcpu *vcpu) +{ + switch (kvm_psci_version(vcpu)) { + case KVM_ARM_PSCI_0_2: + return kvm_psci_0_2_call(vcpu); + case KVM_ARM_PSCI_0_1: + return kvm_psci_0_1_call(vcpu); + default: + return false; + }; +} diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 0a1d697..92242ce 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -39,7 +39,7 @@ #include <kvm/arm_vgic.h> #include <kvm/arm_arch_timer.h>
-#define KVM_VCPU_MAX_FEATURES 2 +#define KVM_VCPU_MAX_FEATURES 3
struct kvm_vcpu; int kvm_target_cpu(void); diff --git a/arch/arm64/include/asm/kvm_psci.h b/arch/arm64/include/asm/kvm_psci.h index e301a48..e25c658 100644 --- a/arch/arm64/include/asm/kvm_psci.h +++ b/arch/arm64/include/asm/kvm_psci.h @@ -18,6 +18,10 @@ #ifndef __ARM64_KVM_PSCI_H__ #define __ARM64_KVM_PSCI_H__
+#define KVM_ARM_PSCI_0_1 1 +#define KVM_ARM_PSCI_0_2 2 + +int kvm_psci_version(struct kvm_vcpu *vcpu); bool kvm_psci_call(struct kvm_vcpu *vcpu);
#endif /* __ARM64_KVM_PSCI_H__ */ diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index d9f026b..b7555d3 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -77,6 +77,7 @@ struct kvm_regs {
#define KVM_ARM_VCPU_POWER_OFF 0 /* CPU is started in OFF state */ #define KVM_ARM_VCPU_EL1_32BIT 1 /* CPU running a 32bit VM */ +#define KVM_ARM_VCPU_PSCI_0_2 2 /* CPU uses PSCI v0.2 */
struct kvm_vcpu_init { __u32 target; @@ -150,7 +151,7 @@ struct kvm_arch_memory_slot { /* Highest supported SPI, from VGIC_NR_IRQS */ #define KVM_ARM_IRQ_GIC_MAX 127
-/* PSCI interface */ +/* PSCI v0.1 interface */ #define KVM_PSCI_FN_BASE 0x95c1ba5e #define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n))
@@ -159,10 +160,42 @@ struct kvm_arch_memory_slot { #define KVM_PSCI_FN_CPU_ON KVM_PSCI_FN(2) #define KVM_PSCI_FN_MIGRATE KVM_PSCI_FN(3)
+/* PSCI v0.2 interface */ +#define KVM_PSCI_0_2_FN_BASE 0x84000000 +#define KVM_PSCI_0_2_FN(n) (KVM_PSCI_0_2_FN_BASE + (n)) +#define KVM_PSCI_0_2_FN64_BASE 0xC4000000 +#define KVM_PSCI_0_2_FN64(n) (KVM_PSCI_0_2_FN64_BASE + (n)) + +#define KVM_PSCI_0_2_FN_PSCI_VERSION KVM_PSCI_0_2_FN(0) +#define KVM_PSCI_0_2_FN_CPU_SUSPEND KVM_PSCI_0_2_FN(1) +#define KVM_PSCI_0_2_FN_CPU_OFF KVM_PSCI_0_2_FN(2) +#define KVM_PSCI_0_2_FN_CPU_ON KVM_PSCI_0_2_FN(3) +#define KVM_PSCI_0_2_FN_AFFINITY_INFO KVM_PSCI_0_2_FN(4) +#define KVM_PSCI_0_2_FN_MIGRATE KVM_PSCI_0_2_FN(5) +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \ + KVM_PSCI_0_2_FN(6) +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \ + KVM_PSCI_0_2_FN(7) +#define KVM_PSCI_0_2_FN_SYSTEM_OFF KVM_PSCI_0_2_FN(8) +#define KVM_PSCI_0_2_FN_SYSTEM_RESET KVM_PSCI_0_2_FN(9) + +#define KVM_PSCI_0_2_FN64_CPU_SUSPEND KVM_PSCI_0_2_FN64(1) +#define KVM_PSCI_0_2_FN64_CPU_ON KVM_PSCI_0_2_FN64(3) +#define KVM_PSCI_0_2_FN64_AFFINITY_INFO KVM_PSCI_0_2_FN64(4) +#define KVM_PSCI_0_2_FN64_MIGRATE KVM_PSCI_0_2_FN64(5) +#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \ + KVM_PSCI_0_2_FN64(7) + +/* PSCI return values */ #define KVM_PSCI_RET_SUCCESS 0 #define KVM_PSCI_RET_NI ((unsigned long)-1) #define KVM_PSCI_RET_INVAL ((unsigned long)-2) #define KVM_PSCI_RET_DENIED ((unsigned long)-3) +#define KVM_PSCI_RET_ALREADY_ON ((unsigned long)-4) +#define KVM_PSCI_RET_ON_PENDING ((unsigned long)-5) +#define KVM_PSCI_RET_INTERNAL_FAILURE ((unsigned long)-6) +#define KVM_PSCI_RET_NOT_PRESENT ((unsigned long)-7) +#define KVM_PSCI_RET_DISABLED ((unsigned long)-8)
#endif
On Thu, Jan 30, 2014 at 04:11:18PM +0530, Anup Patel wrote:
Currently, the in-kernel PSCI emulation provides PSCI v0.1 interface to VCPUs. This patch extends current in-kernel PSCI emulation to provide PSCI v0.2 interface to VCPUs.
By default, ARM/ARM64 KVM will always provide PSCI v0.1 interface for keeping the ABI backward-compatible.
To select PSCI v0.2 interface for VCPUs, the user space (i.e. QEMU or KVMTOOL) will have to set KVM_ARM_VCPU_PSCI_0_2 feature when doing VCPU init using KVM_ARM_VCPU_INIT ioctl.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org
arch/arm/include/asm/kvm_host.h | 2 +- arch/arm/include/asm/kvm_psci.h | 4 ++ arch/arm/include/uapi/asm/kvm.h | 35 ++++++++++++++- arch/arm/kvm/arm.c | 1 + arch/arm/kvm/psci.c | 85 +++++++++++++++++++++++++++++++------ arch/arm64/include/asm/kvm_host.h | 2 +- arch/arm64/include/asm/kvm_psci.h | 4 ++ arch/arm64/include/uapi/asm/kvm.h | 35 ++++++++++++++- 8 files changed, 152 insertions(+), 16 deletions(-)
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index bce6d32..dc4e3ed 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -36,7 +36,7 @@ #define KVM_COALESCED_MMIO_PAGE_OFFSET 1 #define KVM_HAVE_ONE_REG -#define KVM_VCPU_MAX_FEATURES 1 +#define KVM_VCPU_MAX_FEATURES 2 #include <kvm/arm_vgic.h> diff --git a/arch/arm/include/asm/kvm_psci.h b/arch/arm/include/asm/kvm_psci.h index 9a83d98..4c0e3e1 100644 --- a/arch/arm/include/asm/kvm_psci.h +++ b/arch/arm/include/asm/kvm_psci.h @@ -18,6 +18,10 @@ #ifndef __ARM_KVM_PSCI_H__ #define __ARM_KVM_PSCI_H__ +#define KVM_ARM_PSCI_0_1 1 +#define KVM_ARM_PSCI_0_2 2
+int kvm_psci_version(struct kvm_vcpu *vcpu); bool kvm_psci_call(struct kvm_vcpu *vcpu); #endif /* __ARM_KVM_PSCI_H__ */ diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h index c498b60..bf860e2 100644 --- a/arch/arm/include/uapi/asm/kvm.h +++ b/arch/arm/include/uapi/asm/kvm.h @@ -83,6 +83,7 @@ struct kvm_regs { #define KVM_VGIC_V2_CPU_SIZE 0x2000 #define KVM_ARM_VCPU_POWER_OFF 0 /* CPU is started in OFF state */ +#define KVM_ARM_VCPU_PSCI_0_2 1 /* CPU uses PSCI v0.2 */ struct kvm_vcpu_init { __u32 target; @@ -164,7 +165,7 @@ struct kvm_arch_memory_slot { /* Highest supported SPI, from VGIC_NR_IRQS */ #define KVM_ARM_IRQ_GIC_MAX 127 -/* PSCI interface */ +/* PSCI v0.1 interface */ #define KVM_PSCI_FN_BASE 0x95c1ba5e #define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n)) @@ -173,9 +174,41 @@ struct kvm_arch_memory_slot { #define KVM_PSCI_FN_CPU_ON KVM_PSCI_FN(2) #define KVM_PSCI_FN_MIGRATE KVM_PSCI_FN(3) +/* PSCI v0.2 interface */ +#define KVM_PSCI_0_2_FN_BASE 0x84000000 +#define KVM_PSCI_0_2_FN(n) (KVM_PSCI_0_2_FN_BASE + (n)) +#define KVM_PSCI_0_2_FN64_BASE 0xC4000000 +#define KVM_PSCI_0_2_FN64(n) (KVM_PSCI_0_2_FN64_BASE + (n))
+#define KVM_PSCI_0_2_FN_PSCI_VERSION KVM_PSCI_0_2_FN(0) +#define KVM_PSCI_0_2_FN_CPU_SUSPEND KVM_PSCI_0_2_FN(1) +#define KVM_PSCI_0_2_FN_CPU_OFF KVM_PSCI_0_2_FN(2) +#define KVM_PSCI_0_2_FN_CPU_ON KVM_PSCI_0_2_FN(3) +#define KVM_PSCI_0_2_FN_AFFINITY_INFO KVM_PSCI_0_2_FN(4) +#define KVM_PSCI_0_2_FN_MIGRATE KVM_PSCI_0_2_FN(5) +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \
KVM_PSCI_0_2_FN(6)
+#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN(7)
+#define KVM_PSCI_0_2_FN_SYSTEM_OFF KVM_PSCI_0_2_FN(8) +#define KVM_PSCI_0_2_FN_SYSTEM_RESET KVM_PSCI_0_2_FN(9)
+#define KVM_PSCI_0_2_FN64_CPU_SUSPEND KVM_PSCI_0_2_FN64(1) +#define KVM_PSCI_0_2_FN64_CPU_ON KVM_PSCI_0_2_FN64(3) +#define KVM_PSCI_0_2_FN64_AFFINITY_INFO KVM_PSCI_0_2_FN64(4) +#define KVM_PSCI_0_2_FN64_MIGRATE KVM_PSCI_0_2_FN64(5) +#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN64(7)
+/* PSCI return values */ #define KVM_PSCI_RET_SUCCESS 0 #define KVM_PSCI_RET_NI ((unsigned long)-1) #define KVM_PSCI_RET_INVAL ((unsigned long)-2) #define KVM_PSCI_RET_DENIED ((unsigned long)-3) +#define KVM_PSCI_RET_ALREADY_ON ((unsigned long)-4) +#define KVM_PSCI_RET_ON_PENDING ((unsigned long)-5) +#define KVM_PSCI_RET_INTERNAL_FAILURE ((unsigned long)-6) +#define KVM_PSCI_RET_NOT_PRESENT ((unsigned long)-7) +#define KVM_PSCI_RET_DISABLED ((unsigned long)-8) #endif /* __ARM_KVM_H__ */ diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 151eb91..e508125 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -193,6 +193,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: case KVM_CAP_ONE_REG: case KVM_CAP_ARM_PSCI:
- case KVM_CAP_ARM_PSCI_0_2: r = 1; break; case KVM_CAP_COALESCED_MMIO:
diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index 448f60e..7fdc881 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -85,17 +85,57 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) return KVM_PSCI_RET_SUCCESS; } -/**
- kvm_psci_call - handle PSCI call if r0 value is in range
- @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.
- */
-bool kvm_psci_call(struct kvm_vcpu *vcpu) +int kvm_psci_version(struct kvm_vcpu *vcpu) +{
- if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
return KVM_ARM_PSCI_0_2;
- return KVM_ARM_PSCI_0_1;
+}
+static bool kvm_psci_0_2_call(struct kvm_vcpu *vcpu) +{
- unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0);
- unsigned long val;
- switch (psci_fn) {
- case KVM_PSCI_0_2_FN_PSCI_VERSION:
/*
* Bits[31:16] = Major Version = 0
* Bits[15:0] = Minor Version = 2
*/
val = 2;
break;
- case KVM_PSCI_0_2_FN_CPU_OFF:
kvm_psci_vcpu_off(vcpu);
val = KVM_PSCI_RET_SUCCESS;
break;
- case KVM_PSCI_0_2_FN_CPU_ON:
- case KVM_PSCI_0_2_FN64_CPU_ON:
val = kvm_psci_vcpu_on(vcpu);
break;
- case KVM_PSCI_0_2_FN_CPU_SUSPEND:
- case KVM_PSCI_0_2_FN_AFFINITY_INFO:
- case KVM_PSCI_0_2_FN_MIGRATE:
- case KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE:
- case KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU:
- case KVM_PSCI_0_2_FN_SYSTEM_OFF:
- case KVM_PSCI_0_2_FN_SYSTEM_RESET:
- case KVM_PSCI_0_2_FN64_CPU_SUSPEND:
- case KVM_PSCI_0_2_FN64_AFFINITY_INFO:
- case KVM_PSCI_0_2_FN64_MIGRATE:
- case KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU:
val = KVM_PSCI_RET_NI;
break;
- default:
return false;
- }
- *vcpu_reg(vcpu, 0) = val;
- return true;
+}
+static bool kvm_psci_0_1_call(struct kvm_vcpu *vcpu) { unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); unsigned long val; @@ -112,7 +152,6 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu) case KVM_PSCI_FN_MIGRATE: val = KVM_PSCI_RET_NI; break;
- default: return false; }
@@ -120,3 +159,25 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu) *vcpu_reg(vcpu, 0) = val; return true; }
+/**
- kvm_psci_call - handle PSCI call if r0 value is in range
- @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.
- */
+bool kvm_psci_call(struct kvm_vcpu *vcpu) +{
- switch (kvm_psci_version(vcpu)) {
- case KVM_ARM_PSCI_0_2:
return kvm_psci_0_2_call(vcpu);
- case KVM_ARM_PSCI_0_1:
return kvm_psci_0_1_call(vcpu);
- default:
return false;
- };
+} diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 0a1d697..92242ce 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -39,7 +39,7 @@ #include <kvm/arm_vgic.h> #include <kvm/arm_arch_timer.h> -#define KVM_VCPU_MAX_FEATURES 2 +#define KVM_VCPU_MAX_FEATURES 3 struct kvm_vcpu; int kvm_target_cpu(void); diff --git a/arch/arm64/include/asm/kvm_psci.h b/arch/arm64/include/asm/kvm_psci.h index e301a48..e25c658 100644 --- a/arch/arm64/include/asm/kvm_psci.h +++ b/arch/arm64/include/asm/kvm_psci.h @@ -18,6 +18,10 @@ #ifndef __ARM64_KVM_PSCI_H__ #define __ARM64_KVM_PSCI_H__ +#define KVM_ARM_PSCI_0_1 1 +#define KVM_ARM_PSCI_0_2 2
+int kvm_psci_version(struct kvm_vcpu *vcpu); bool kvm_psci_call(struct kvm_vcpu *vcpu); #endif /* __ARM64_KVM_PSCI_H__ */ diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index d9f026b..b7555d3 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -77,6 +77,7 @@ struct kvm_regs { #define KVM_ARM_VCPU_POWER_OFF 0 /* CPU is started in OFF state */ #define KVM_ARM_VCPU_EL1_32BIT 1 /* CPU running a 32bit VM */ +#define KVM_ARM_VCPU_PSCI_0_2 2 /* CPU uses PSCI v0.2 */ struct kvm_vcpu_init { __u32 target; @@ -150,7 +151,7 @@ struct kvm_arch_memory_slot { /* Highest supported SPI, from VGIC_NR_IRQS */ #define KVM_ARM_IRQ_GIC_MAX 127 -/* PSCI interface */ +/* PSCI v0.1 interface */ #define KVM_PSCI_FN_BASE 0x95c1ba5e #define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n)) @@ -159,10 +160,42 @@ struct kvm_arch_memory_slot { #define KVM_PSCI_FN_CPU_ON KVM_PSCI_FN(2) #define KVM_PSCI_FN_MIGRATE KVM_PSCI_FN(3) +/* PSCI v0.2 interface */ +#define KVM_PSCI_0_2_FN_BASE 0x84000000 +#define KVM_PSCI_0_2_FN(n) (KVM_PSCI_0_2_FN_BASE + (n)) +#define KVM_PSCI_0_2_FN64_BASE 0xC4000000 +#define KVM_PSCI_0_2_FN64(n) (KVM_PSCI_0_2_FN64_BASE + (n))
+#define KVM_PSCI_0_2_FN_PSCI_VERSION KVM_PSCI_0_2_FN(0) +#define KVM_PSCI_0_2_FN_CPU_SUSPEND KVM_PSCI_0_2_FN(1) +#define KVM_PSCI_0_2_FN_CPU_OFF KVM_PSCI_0_2_FN(2) +#define KVM_PSCI_0_2_FN_CPU_ON KVM_PSCI_0_2_FN(3) +#define KVM_PSCI_0_2_FN_AFFINITY_INFO KVM_PSCI_0_2_FN(4) +#define KVM_PSCI_0_2_FN_MIGRATE KVM_PSCI_0_2_FN(5) +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \
KVM_PSCI_0_2_FN(6)
+#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN(7)
+#define KVM_PSCI_0_2_FN_SYSTEM_OFF KVM_PSCI_0_2_FN(8) +#define KVM_PSCI_0_2_FN_SYSTEM_RESET KVM_PSCI_0_2_FN(9)
+#define KVM_PSCI_0_2_FN64_CPU_SUSPEND KVM_PSCI_0_2_FN64(1) +#define KVM_PSCI_0_2_FN64_CPU_ON KVM_PSCI_0_2_FN64(3) +#define KVM_PSCI_0_2_FN64_AFFINITY_INFO KVM_PSCI_0_2_FN64(4) +#define KVM_PSCI_0_2_FN64_MIGRATE KVM_PSCI_0_2_FN64(5) +#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN64(7)
+/* PSCI return values */ #define KVM_PSCI_RET_SUCCESS 0 #define KVM_PSCI_RET_NI ((unsigned long)-1) #define KVM_PSCI_RET_INVAL ((unsigned long)-2) #define KVM_PSCI_RET_DENIED ((unsigned long)-3) +#define KVM_PSCI_RET_ALREADY_ON ((unsigned long)-4) +#define KVM_PSCI_RET_ON_PENDING ((unsigned long)-5) +#define KVM_PSCI_RET_INTERNAL_FAILURE ((unsigned long)-6) +#define KVM_PSCI_RET_NOT_PRESENT ((unsigned long)-7) +#define KVM_PSCI_RET_DISABLED ((unsigned long)-8) #endif -- 1.7.9.5
Reviewed-by: Christoffer Dall christoffer.dall@linaro.org
On Thu, Jan 30, 2014 at 10:41:18AM +0000, Anup Patel wrote:
Currently, the in-kernel PSCI emulation provides PSCI v0.1 interface to VCPUs. This patch extends current in-kernel PSCI emulation to provide PSCI v0.2 interface to VCPUs.
By default, ARM/ARM64 KVM will always provide PSCI v0.1 interface for keeping the ABI backward-compatible.
To select PSCI v0.2 interface for VCPUs, the user space (i.e. QEMU or KVMTOOL) will have to set KVM_ARM_VCPU_PSCI_0_2 feature when doing VCPU init using KVM_ARM_VCPU_INIT ioctl.
I have an issue with this. PSCI 0.2 makes all but two functions (MIGRATE and MIGRATE_INFO_CPU_UP) mandatory, and hence not allowed to return NOT_SUPPORTED.
Additionally, for correct behaviour across a kexec in future, we'll require AFFINITY_INFO for PSCI 0.2+ systems to determint when a CPU is actually dead (and cannot affect the cache hierarchy). I'd very much like to make that a hard requirement to ensure correctness.
I would very much like to see at least trivial implementations of those mandatory functions, so that we don't need a KVM_ARM_VCPU_PSCI_REALLY_0_2 or similar in future. As it stands this series does not implement PSCI 0.2.
Thanks, Mark.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org
arch/arm/include/asm/kvm_host.h | 2 +- arch/arm/include/asm/kvm_psci.h | 4 ++ arch/arm/include/uapi/asm/kvm.h | 35 ++++++++++++++- arch/arm/kvm/arm.c | 1 + arch/arm/kvm/psci.c | 85 +++++++++++++++++++++++++++++++------ arch/arm64/include/asm/kvm_host.h | 2 +- arch/arm64/include/asm/kvm_psci.h | 4 ++ arch/arm64/include/uapi/asm/kvm.h | 35 ++++++++++++++- 8 files changed, 152 insertions(+), 16 deletions(-)
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index bce6d32..dc4e3ed 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -36,7 +36,7 @@ #define KVM_COALESCED_MMIO_PAGE_OFFSET 1 #define KVM_HAVE_ONE_REG
-#define KVM_VCPU_MAX_FEATURES 1 +#define KVM_VCPU_MAX_FEATURES 2
#include <kvm/arm_vgic.h>
diff --git a/arch/arm/include/asm/kvm_psci.h b/arch/arm/include/asm/kvm_psci.h index 9a83d98..4c0e3e1 100644 --- a/arch/arm/include/asm/kvm_psci.h +++ b/arch/arm/include/asm/kvm_psci.h @@ -18,6 +18,10 @@ #ifndef __ARM_KVM_PSCI_H__ #define __ARM_KVM_PSCI_H__
+#define KVM_ARM_PSCI_0_1 1 +#define KVM_ARM_PSCI_0_2 2
+int kvm_psci_version(struct kvm_vcpu *vcpu); bool kvm_psci_call(struct kvm_vcpu *vcpu);
#endif /* __ARM_KVM_PSCI_H__ */ diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h index c498b60..bf860e2 100644 --- a/arch/arm/include/uapi/asm/kvm.h +++ b/arch/arm/include/uapi/asm/kvm.h @@ -83,6 +83,7 @@ struct kvm_regs { #define KVM_VGIC_V2_CPU_SIZE 0x2000
#define KVM_ARM_VCPU_POWER_OFF 0 /* CPU is started in OFF state */ +#define KVM_ARM_VCPU_PSCI_0_2 1 /* CPU uses PSCI v0.2 */
struct kvm_vcpu_init { __u32 target; @@ -164,7 +165,7 @@ struct kvm_arch_memory_slot { /* Highest supported SPI, from VGIC_NR_IRQS */ #define KVM_ARM_IRQ_GIC_MAX 127
-/* PSCI interface */ +/* PSCI v0.1 interface */ #define KVM_PSCI_FN_BASE 0x95c1ba5e #define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n))
@@ -173,9 +174,41 @@ struct kvm_arch_memory_slot { #define KVM_PSCI_FN_CPU_ON KVM_PSCI_FN(2) #define KVM_PSCI_FN_MIGRATE KVM_PSCI_FN(3)
+/* PSCI v0.2 interface */ +#define KVM_PSCI_0_2_FN_BASE 0x84000000 +#define KVM_PSCI_0_2_FN(n) (KVM_PSCI_0_2_FN_BASE + (n)) +#define KVM_PSCI_0_2_FN64_BASE 0xC4000000 +#define KVM_PSCI_0_2_FN64(n) (KVM_PSCI_0_2_FN64_BASE + (n))
+#define KVM_PSCI_0_2_FN_PSCI_VERSION KVM_PSCI_0_2_FN(0) +#define KVM_PSCI_0_2_FN_CPU_SUSPEND KVM_PSCI_0_2_FN(1) +#define KVM_PSCI_0_2_FN_CPU_OFF KVM_PSCI_0_2_FN(2) +#define KVM_PSCI_0_2_FN_CPU_ON KVM_PSCI_0_2_FN(3) +#define KVM_PSCI_0_2_FN_AFFINITY_INFO KVM_PSCI_0_2_FN(4) +#define KVM_PSCI_0_2_FN_MIGRATE KVM_PSCI_0_2_FN(5) +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \
KVM_PSCI_0_2_FN(6)
+#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN(7)
+#define KVM_PSCI_0_2_FN_SYSTEM_OFF KVM_PSCI_0_2_FN(8) +#define KVM_PSCI_0_2_FN_SYSTEM_RESET KVM_PSCI_0_2_FN(9)
+#define KVM_PSCI_0_2_FN64_CPU_SUSPEND KVM_PSCI_0_2_FN64(1) +#define KVM_PSCI_0_2_FN64_CPU_ON KVM_PSCI_0_2_FN64(3) +#define KVM_PSCI_0_2_FN64_AFFINITY_INFO KVM_PSCI_0_2_FN64(4) +#define KVM_PSCI_0_2_FN64_MIGRATE KVM_PSCI_0_2_FN64(5) +#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN64(7)
+/* PSCI return values */ #define KVM_PSCI_RET_SUCCESS 0 #define KVM_PSCI_RET_NI ((unsigned long)-1) #define KVM_PSCI_RET_INVAL ((unsigned long)-2) #define KVM_PSCI_RET_DENIED ((unsigned long)-3) +#define KVM_PSCI_RET_ALREADY_ON ((unsigned long)-4) +#define KVM_PSCI_RET_ON_PENDING ((unsigned long)-5) +#define KVM_PSCI_RET_INTERNAL_FAILURE ((unsigned long)-6) +#define KVM_PSCI_RET_NOT_PRESENT ((unsigned long)-7) +#define KVM_PSCI_RET_DISABLED ((unsigned long)-8)
#endif /* __ARM_KVM_H__ */ diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 151eb91..e508125 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -193,6 +193,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: case KVM_CAP_ONE_REG: case KVM_CAP_ARM_PSCI:
case KVM_CAP_ARM_PSCI_0_2: r = 1; break; case KVM_CAP_COALESCED_MMIO:
diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index 448f60e..7fdc881 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -85,17 +85,57 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) return KVM_PSCI_RET_SUCCESS; }
-/**
- kvm_psci_call - handle PSCI call if r0 value is in range
- @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.
- */
-bool kvm_psci_call(struct kvm_vcpu *vcpu) +int kvm_psci_version(struct kvm_vcpu *vcpu) +{
if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
return KVM_ARM_PSCI_0_2;
return KVM_ARM_PSCI_0_1;
+}
+static bool kvm_psci_0_2_call(struct kvm_vcpu *vcpu) +{
unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0);
unsigned long val;
switch (psci_fn) {
case KVM_PSCI_0_2_FN_PSCI_VERSION:
/*
* Bits[31:16] = Major Version = 0
* Bits[15:0] = Minor Version = 2
*/
val = 2;
break;
case KVM_PSCI_0_2_FN_CPU_OFF:
kvm_psci_vcpu_off(vcpu);
val = KVM_PSCI_RET_SUCCESS;
break;
case KVM_PSCI_0_2_FN_CPU_ON:
case KVM_PSCI_0_2_FN64_CPU_ON:
val = kvm_psci_vcpu_on(vcpu);
break;
case KVM_PSCI_0_2_FN_CPU_SUSPEND:
case KVM_PSCI_0_2_FN_AFFINITY_INFO:
case KVM_PSCI_0_2_FN_MIGRATE:
case KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE:
case KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU:
case KVM_PSCI_0_2_FN_SYSTEM_OFF:
case KVM_PSCI_0_2_FN_SYSTEM_RESET:
case KVM_PSCI_0_2_FN64_CPU_SUSPEND:
case KVM_PSCI_0_2_FN64_AFFINITY_INFO:
case KVM_PSCI_0_2_FN64_MIGRATE:
case KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU:
val = KVM_PSCI_RET_NI;
break;
default:
return false;
}
*vcpu_reg(vcpu, 0) = val;
return true;
+}
+static bool kvm_psci_0_1_call(struct kvm_vcpu *vcpu) { unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); unsigned long val; @@ -112,7 +152,6 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu) case KVM_PSCI_FN_MIGRATE: val = KVM_PSCI_RET_NI; break;
default: return false; }
@@ -120,3 +159,25 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu) *vcpu_reg(vcpu, 0) = val; return true; }
+/**
- kvm_psci_call - handle PSCI call if r0 value is in range
- @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.
- */
+bool kvm_psci_call(struct kvm_vcpu *vcpu) +{
switch (kvm_psci_version(vcpu)) {
case KVM_ARM_PSCI_0_2:
return kvm_psci_0_2_call(vcpu);
case KVM_ARM_PSCI_0_1:
return kvm_psci_0_1_call(vcpu);
default:
return false;
};
+} diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 0a1d697..92242ce 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -39,7 +39,7 @@ #include <kvm/arm_vgic.h> #include <kvm/arm_arch_timer.h>
-#define KVM_VCPU_MAX_FEATURES 2 +#define KVM_VCPU_MAX_FEATURES 3
struct kvm_vcpu; int kvm_target_cpu(void); diff --git a/arch/arm64/include/asm/kvm_psci.h b/arch/arm64/include/asm/kvm_psci.h index e301a48..e25c658 100644 --- a/arch/arm64/include/asm/kvm_psci.h +++ b/arch/arm64/include/asm/kvm_psci.h @@ -18,6 +18,10 @@ #ifndef __ARM64_KVM_PSCI_H__ #define __ARM64_KVM_PSCI_H__
+#define KVM_ARM_PSCI_0_1 1 +#define KVM_ARM_PSCI_0_2 2
+int kvm_psci_version(struct kvm_vcpu *vcpu); bool kvm_psci_call(struct kvm_vcpu *vcpu);
#endif /* __ARM64_KVM_PSCI_H__ */ diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index d9f026b..b7555d3 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -77,6 +77,7 @@ struct kvm_regs {
#define KVM_ARM_VCPU_POWER_OFF 0 /* CPU is started in OFF state */ #define KVM_ARM_VCPU_EL1_32BIT 1 /* CPU running a 32bit VM */ +#define KVM_ARM_VCPU_PSCI_0_2 2 /* CPU uses PSCI v0.2 */
struct kvm_vcpu_init { __u32 target; @@ -150,7 +151,7 @@ struct kvm_arch_memory_slot { /* Highest supported SPI, from VGIC_NR_IRQS */ #define KVM_ARM_IRQ_GIC_MAX 127
-/* PSCI interface */ +/* PSCI v0.1 interface */ #define KVM_PSCI_FN_BASE 0x95c1ba5e #define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n))
@@ -159,10 +160,42 @@ struct kvm_arch_memory_slot { #define KVM_PSCI_FN_CPU_ON KVM_PSCI_FN(2) #define KVM_PSCI_FN_MIGRATE KVM_PSCI_FN(3)
+/* PSCI v0.2 interface */ +#define KVM_PSCI_0_2_FN_BASE 0x84000000 +#define KVM_PSCI_0_2_FN(n) (KVM_PSCI_0_2_FN_BASE + (n)) +#define KVM_PSCI_0_2_FN64_BASE 0xC4000000 +#define KVM_PSCI_0_2_FN64(n) (KVM_PSCI_0_2_FN64_BASE + (n))
+#define KVM_PSCI_0_2_FN_PSCI_VERSION KVM_PSCI_0_2_FN(0) +#define KVM_PSCI_0_2_FN_CPU_SUSPEND KVM_PSCI_0_2_FN(1) +#define KVM_PSCI_0_2_FN_CPU_OFF KVM_PSCI_0_2_FN(2) +#define KVM_PSCI_0_2_FN_CPU_ON KVM_PSCI_0_2_FN(3) +#define KVM_PSCI_0_2_FN_AFFINITY_INFO KVM_PSCI_0_2_FN(4) +#define KVM_PSCI_0_2_FN_MIGRATE KVM_PSCI_0_2_FN(5) +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \
KVM_PSCI_0_2_FN(6)
+#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN(7)
+#define KVM_PSCI_0_2_FN_SYSTEM_OFF KVM_PSCI_0_2_FN(8) +#define KVM_PSCI_0_2_FN_SYSTEM_RESET KVM_PSCI_0_2_FN(9)
+#define KVM_PSCI_0_2_FN64_CPU_SUSPEND KVM_PSCI_0_2_FN64(1) +#define KVM_PSCI_0_2_FN64_CPU_ON KVM_PSCI_0_2_FN64(3) +#define KVM_PSCI_0_2_FN64_AFFINITY_INFO KVM_PSCI_0_2_FN64(4) +#define KVM_PSCI_0_2_FN64_MIGRATE KVM_PSCI_0_2_FN64(5) +#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN64(7)
+/* PSCI return values */ #define KVM_PSCI_RET_SUCCESS 0 #define KVM_PSCI_RET_NI ((unsigned long)-1) #define KVM_PSCI_RET_INVAL ((unsigned long)-2) #define KVM_PSCI_RET_DENIED ((unsigned long)-3) +#define KVM_PSCI_RET_ALREADY_ON ((unsigned long)-4) +#define KVM_PSCI_RET_ON_PENDING ((unsigned long)-5) +#define KVM_PSCI_RET_INTERNAL_FAILURE ((unsigned long)-6) +#define KVM_PSCI_RET_NOT_PRESENT ((unsigned long)-7) +#define KVM_PSCI_RET_DISABLED ((unsigned long)-8)
#endif
-- 1.7.9.5
Hi Mark,
On Mon, Feb 3, 2014 at 4:24 PM, Mark Rutland mark.rutland@arm.com wrote:
On Thu, Jan 30, 2014 at 10:41:18AM +0000, Anup Patel wrote:
Currently, the in-kernel PSCI emulation provides PSCI v0.1 interface to VCPUs. This patch extends current in-kernel PSCI emulation to provide PSCI v0.2 interface to VCPUs.
By default, ARM/ARM64 KVM will always provide PSCI v0.1 interface for keeping the ABI backward-compatible.
To select PSCI v0.2 interface for VCPUs, the user space (i.e. QEMU or KVMTOOL) will have to set KVM_ARM_VCPU_PSCI_0_2 feature when doing VCPU init using KVM_ARM_VCPU_INIT ioctl.
I have an issue with this. PSCI 0.2 makes all but two functions (MIGRATE and MIGRATE_INFO_CPU_UP) mandatory, and hence not allowed to return NOT_SUPPORTED.
Additionally, for correct behaviour across a kexec in future, we'll require AFFINITY_INFO for PSCI 0.2+ systems to determint when a CPU is actually dead (and cannot affect the cache hierarchy). I'd very much like to make that a hard requirement to ensure correctness.
I would very much like to see at least trivial implementations of those mandatory functions, so that we don't need a KVM_ARM_VCPU_PSCI_REALLY_0_2 or similar in future. As it stands this series does not implement PSCI 0.2.
The intention behind this series was to provide a base implementation of PSCI v0.2 which can be extended by subsequent patches that implement other PSCI v0.2 functions.
I already have a patch series that implement PSCI v0.2 SYSTEM_OFF and SYSTEM_RESET based on this series.
Regards, Anup
Thanks, Mark.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org
arch/arm/include/asm/kvm_host.h | 2 +- arch/arm/include/asm/kvm_psci.h | 4 ++ arch/arm/include/uapi/asm/kvm.h | 35 ++++++++++++++- arch/arm/kvm/arm.c | 1 + arch/arm/kvm/psci.c | 85 +++++++++++++++++++++++++++++++------ arch/arm64/include/asm/kvm_host.h | 2 +- arch/arm64/include/asm/kvm_psci.h | 4 ++ arch/arm64/include/uapi/asm/kvm.h | 35 ++++++++++++++- 8 files changed, 152 insertions(+), 16 deletions(-)
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index bce6d32..dc4e3ed 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -36,7 +36,7 @@ #define KVM_COALESCED_MMIO_PAGE_OFFSET 1 #define KVM_HAVE_ONE_REG
-#define KVM_VCPU_MAX_FEATURES 1 +#define KVM_VCPU_MAX_FEATURES 2
#include <kvm/arm_vgic.h>
diff --git a/arch/arm/include/asm/kvm_psci.h b/arch/arm/include/asm/kvm_psci.h index 9a83d98..4c0e3e1 100644 --- a/arch/arm/include/asm/kvm_psci.h +++ b/arch/arm/include/asm/kvm_psci.h @@ -18,6 +18,10 @@ #ifndef __ARM_KVM_PSCI_H__ #define __ARM_KVM_PSCI_H__
+#define KVM_ARM_PSCI_0_1 1 +#define KVM_ARM_PSCI_0_2 2
+int kvm_psci_version(struct kvm_vcpu *vcpu); bool kvm_psci_call(struct kvm_vcpu *vcpu);
#endif /* __ARM_KVM_PSCI_H__ */ diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h index c498b60..bf860e2 100644 --- a/arch/arm/include/uapi/asm/kvm.h +++ b/arch/arm/include/uapi/asm/kvm.h @@ -83,6 +83,7 @@ struct kvm_regs { #define KVM_VGIC_V2_CPU_SIZE 0x2000
#define KVM_ARM_VCPU_POWER_OFF 0 /* CPU is started in OFF state */ +#define KVM_ARM_VCPU_PSCI_0_2 1 /* CPU uses PSCI v0.2 */
struct kvm_vcpu_init { __u32 target; @@ -164,7 +165,7 @@ struct kvm_arch_memory_slot { /* Highest supported SPI, from VGIC_NR_IRQS */ #define KVM_ARM_IRQ_GIC_MAX 127
-/* PSCI interface */ +/* PSCI v0.1 interface */ #define KVM_PSCI_FN_BASE 0x95c1ba5e #define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n))
@@ -173,9 +174,41 @@ struct kvm_arch_memory_slot { #define KVM_PSCI_FN_CPU_ON KVM_PSCI_FN(2) #define KVM_PSCI_FN_MIGRATE KVM_PSCI_FN(3)
+/* PSCI v0.2 interface */ +#define KVM_PSCI_0_2_FN_BASE 0x84000000 +#define KVM_PSCI_0_2_FN(n) (KVM_PSCI_0_2_FN_BASE + (n)) +#define KVM_PSCI_0_2_FN64_BASE 0xC4000000 +#define KVM_PSCI_0_2_FN64(n) (KVM_PSCI_0_2_FN64_BASE + (n))
+#define KVM_PSCI_0_2_FN_PSCI_VERSION KVM_PSCI_0_2_FN(0) +#define KVM_PSCI_0_2_FN_CPU_SUSPEND KVM_PSCI_0_2_FN(1) +#define KVM_PSCI_0_2_FN_CPU_OFF KVM_PSCI_0_2_FN(2) +#define KVM_PSCI_0_2_FN_CPU_ON KVM_PSCI_0_2_FN(3) +#define KVM_PSCI_0_2_FN_AFFINITY_INFO KVM_PSCI_0_2_FN(4) +#define KVM_PSCI_0_2_FN_MIGRATE KVM_PSCI_0_2_FN(5) +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \
KVM_PSCI_0_2_FN(6)
+#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN(7)
+#define KVM_PSCI_0_2_FN_SYSTEM_OFF KVM_PSCI_0_2_FN(8) +#define KVM_PSCI_0_2_FN_SYSTEM_RESET KVM_PSCI_0_2_FN(9)
+#define KVM_PSCI_0_2_FN64_CPU_SUSPEND KVM_PSCI_0_2_FN64(1) +#define KVM_PSCI_0_2_FN64_CPU_ON KVM_PSCI_0_2_FN64(3) +#define KVM_PSCI_0_2_FN64_AFFINITY_INFO KVM_PSCI_0_2_FN64(4) +#define KVM_PSCI_0_2_FN64_MIGRATE KVM_PSCI_0_2_FN64(5) +#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN64(7)
+/* PSCI return values */ #define KVM_PSCI_RET_SUCCESS 0 #define KVM_PSCI_RET_NI ((unsigned long)-1) #define KVM_PSCI_RET_INVAL ((unsigned long)-2) #define KVM_PSCI_RET_DENIED ((unsigned long)-3) +#define KVM_PSCI_RET_ALREADY_ON ((unsigned long)-4) +#define KVM_PSCI_RET_ON_PENDING ((unsigned long)-5) +#define KVM_PSCI_RET_INTERNAL_FAILURE ((unsigned long)-6) +#define KVM_PSCI_RET_NOT_PRESENT ((unsigned long)-7) +#define KVM_PSCI_RET_DISABLED ((unsigned long)-8)
#endif /* __ARM_KVM_H__ */ diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 151eb91..e508125 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -193,6 +193,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: case KVM_CAP_ONE_REG: case KVM_CAP_ARM_PSCI:
case KVM_CAP_ARM_PSCI_0_2: r = 1; break; case KVM_CAP_COALESCED_MMIO:
diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index 448f60e..7fdc881 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -85,17 +85,57 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) return KVM_PSCI_RET_SUCCESS; }
-/**
- kvm_psci_call - handle PSCI call if r0 value is in range
- @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.
- */
-bool kvm_psci_call(struct kvm_vcpu *vcpu) +int kvm_psci_version(struct kvm_vcpu *vcpu) +{
if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
return KVM_ARM_PSCI_0_2;
return KVM_ARM_PSCI_0_1;
+}
+static bool kvm_psci_0_2_call(struct kvm_vcpu *vcpu) +{
unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0);
unsigned long val;
switch (psci_fn) {
case KVM_PSCI_0_2_FN_PSCI_VERSION:
/*
* Bits[31:16] = Major Version = 0
* Bits[15:0] = Minor Version = 2
*/
val = 2;
break;
case KVM_PSCI_0_2_FN_CPU_OFF:
kvm_psci_vcpu_off(vcpu);
val = KVM_PSCI_RET_SUCCESS;
break;
case KVM_PSCI_0_2_FN_CPU_ON:
case KVM_PSCI_0_2_FN64_CPU_ON:
val = kvm_psci_vcpu_on(vcpu);
break;
case KVM_PSCI_0_2_FN_CPU_SUSPEND:
case KVM_PSCI_0_2_FN_AFFINITY_INFO:
case KVM_PSCI_0_2_FN_MIGRATE:
case KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE:
case KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU:
case KVM_PSCI_0_2_FN_SYSTEM_OFF:
case KVM_PSCI_0_2_FN_SYSTEM_RESET:
case KVM_PSCI_0_2_FN64_CPU_SUSPEND:
case KVM_PSCI_0_2_FN64_AFFINITY_INFO:
case KVM_PSCI_0_2_FN64_MIGRATE:
case KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU:
val = KVM_PSCI_RET_NI;
break;
default:
return false;
}
*vcpu_reg(vcpu, 0) = val;
return true;
+}
+static bool kvm_psci_0_1_call(struct kvm_vcpu *vcpu) { unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); unsigned long val; @@ -112,7 +152,6 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu) case KVM_PSCI_FN_MIGRATE: val = KVM_PSCI_RET_NI; break;
default: return false; }
@@ -120,3 +159,25 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu) *vcpu_reg(vcpu, 0) = val; return true; }
+/**
- kvm_psci_call - handle PSCI call if r0 value is in range
- @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.
- */
+bool kvm_psci_call(struct kvm_vcpu *vcpu) +{
switch (kvm_psci_version(vcpu)) {
case KVM_ARM_PSCI_0_2:
return kvm_psci_0_2_call(vcpu);
case KVM_ARM_PSCI_0_1:
return kvm_psci_0_1_call(vcpu);
default:
return false;
};
+} diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 0a1d697..92242ce 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -39,7 +39,7 @@ #include <kvm/arm_vgic.h> #include <kvm/arm_arch_timer.h>
-#define KVM_VCPU_MAX_FEATURES 2 +#define KVM_VCPU_MAX_FEATURES 3
struct kvm_vcpu; int kvm_target_cpu(void); diff --git a/arch/arm64/include/asm/kvm_psci.h b/arch/arm64/include/asm/kvm_psci.h index e301a48..e25c658 100644 --- a/arch/arm64/include/asm/kvm_psci.h +++ b/arch/arm64/include/asm/kvm_psci.h @@ -18,6 +18,10 @@ #ifndef __ARM64_KVM_PSCI_H__ #define __ARM64_KVM_PSCI_H__
+#define KVM_ARM_PSCI_0_1 1 +#define KVM_ARM_PSCI_0_2 2
+int kvm_psci_version(struct kvm_vcpu *vcpu); bool kvm_psci_call(struct kvm_vcpu *vcpu);
#endif /* __ARM64_KVM_PSCI_H__ */ diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index d9f026b..b7555d3 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -77,6 +77,7 @@ struct kvm_regs {
#define KVM_ARM_VCPU_POWER_OFF 0 /* CPU is started in OFF state */ #define KVM_ARM_VCPU_EL1_32BIT 1 /* CPU running a 32bit VM */ +#define KVM_ARM_VCPU_PSCI_0_2 2 /* CPU uses PSCI v0.2 */
struct kvm_vcpu_init { __u32 target; @@ -150,7 +151,7 @@ struct kvm_arch_memory_slot { /* Highest supported SPI, from VGIC_NR_IRQS */ #define KVM_ARM_IRQ_GIC_MAX 127
-/* PSCI interface */ +/* PSCI v0.1 interface */ #define KVM_PSCI_FN_BASE 0x95c1ba5e #define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n))
@@ -159,10 +160,42 @@ struct kvm_arch_memory_slot { #define KVM_PSCI_FN_CPU_ON KVM_PSCI_FN(2) #define KVM_PSCI_FN_MIGRATE KVM_PSCI_FN(3)
+/* PSCI v0.2 interface */ +#define KVM_PSCI_0_2_FN_BASE 0x84000000 +#define KVM_PSCI_0_2_FN(n) (KVM_PSCI_0_2_FN_BASE + (n)) +#define KVM_PSCI_0_2_FN64_BASE 0xC4000000 +#define KVM_PSCI_0_2_FN64(n) (KVM_PSCI_0_2_FN64_BASE + (n))
+#define KVM_PSCI_0_2_FN_PSCI_VERSION KVM_PSCI_0_2_FN(0) +#define KVM_PSCI_0_2_FN_CPU_SUSPEND KVM_PSCI_0_2_FN(1) +#define KVM_PSCI_0_2_FN_CPU_OFF KVM_PSCI_0_2_FN(2) +#define KVM_PSCI_0_2_FN_CPU_ON KVM_PSCI_0_2_FN(3) +#define KVM_PSCI_0_2_FN_AFFINITY_INFO KVM_PSCI_0_2_FN(4) +#define KVM_PSCI_0_2_FN_MIGRATE KVM_PSCI_0_2_FN(5) +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \
KVM_PSCI_0_2_FN(6)
+#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN(7)
+#define KVM_PSCI_0_2_FN_SYSTEM_OFF KVM_PSCI_0_2_FN(8) +#define KVM_PSCI_0_2_FN_SYSTEM_RESET KVM_PSCI_0_2_FN(9)
+#define KVM_PSCI_0_2_FN64_CPU_SUSPEND KVM_PSCI_0_2_FN64(1) +#define KVM_PSCI_0_2_FN64_CPU_ON KVM_PSCI_0_2_FN64(3) +#define KVM_PSCI_0_2_FN64_AFFINITY_INFO KVM_PSCI_0_2_FN64(4) +#define KVM_PSCI_0_2_FN64_MIGRATE KVM_PSCI_0_2_FN64(5) +#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN64(7)
+/* PSCI return values */ #define KVM_PSCI_RET_SUCCESS 0 #define KVM_PSCI_RET_NI ((unsigned long)-1) #define KVM_PSCI_RET_INVAL ((unsigned long)-2) #define KVM_PSCI_RET_DENIED ((unsigned long)-3) +#define KVM_PSCI_RET_ALREADY_ON ((unsigned long)-4) +#define KVM_PSCI_RET_ON_PENDING ((unsigned long)-5) +#define KVM_PSCI_RET_INTERNAL_FAILURE ((unsigned long)-6) +#define KVM_PSCI_RET_NOT_PRESENT ((unsigned long)-7) +#define KVM_PSCI_RET_DISABLED ((unsigned long)-8)
#endif
-- 1.7.9.5
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On Mon, Feb 3, 2014 at 4:46 PM, Anup Patel apatel@apm.com wrote:
Hi Mark,
On Mon, Feb 3, 2014 at 4:24 PM, Mark Rutland mark.rutland@arm.com wrote:
On Thu, Jan 30, 2014 at 10:41:18AM +0000, Anup Patel wrote:
Currently, the in-kernel PSCI emulation provides PSCI v0.1 interface to VCPUs. This patch extends current in-kernel PSCI emulation to provide PSCI v0.2 interface to VCPUs.
By default, ARM/ARM64 KVM will always provide PSCI v0.1 interface for keeping the ABI backward-compatible.
To select PSCI v0.2 interface for VCPUs, the user space (i.e. QEMU or KVMTOOL) will have to set KVM_ARM_VCPU_PSCI_0_2 feature when doing VCPU init using KVM_ARM_VCPU_INIT ioctl.
I have an issue with this. PSCI 0.2 makes all but two functions (MIGRATE and MIGRATE_INFO_CPU_UP) mandatory, and hence not allowed to return NOT_SUPPORTED.
Additionally, for correct behaviour across a kexec in future, we'll require AFFINITY_INFO for PSCI 0.2+ systems to determint when a CPU is actually dead (and cannot affect the cache hierarchy). I'd very much like to make that a hard requirement to ensure correctness.
I would very much like to see at least trivial implementations of those mandatory functions, so that we don't need a KVM_ARM_VCPU_PSCI_REALLY_0_2 or similar in future. As it stands this series does not implement PSCI 0.2.
The intention behind this series was to provide a base implementation of PSCI v0.2 which can be extended by subsequent patches that implement other PSCI v0.2 functions.
I already have a patch series that implement PSCI v0.2 SYSTEM_OFF and SYSTEM_RESET based on this series.
Regards, Anup
Thanks, Mark.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org
arch/arm/include/asm/kvm_host.h | 2 +- arch/arm/include/asm/kvm_psci.h | 4 ++ arch/arm/include/uapi/asm/kvm.h | 35 ++++++++++++++- arch/arm/kvm/arm.c | 1 + arch/arm/kvm/psci.c | 85 +++++++++++++++++++++++++++++++------ arch/arm64/include/asm/kvm_host.h | 2 +- arch/arm64/include/asm/kvm_psci.h | 4 ++ arch/arm64/include/uapi/asm/kvm.h | 35 ++++++++++++++- 8 files changed, 152 insertions(+), 16 deletions(-)
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index bce6d32..dc4e3ed 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -36,7 +36,7 @@ #define KVM_COALESCED_MMIO_PAGE_OFFSET 1 #define KVM_HAVE_ONE_REG
-#define KVM_VCPU_MAX_FEATURES 1 +#define KVM_VCPU_MAX_FEATURES 2
#include <kvm/arm_vgic.h>
diff --git a/arch/arm/include/asm/kvm_psci.h b/arch/arm/include/asm/kvm_psci.h index 9a83d98..4c0e3e1 100644 --- a/arch/arm/include/asm/kvm_psci.h +++ b/arch/arm/include/asm/kvm_psci.h @@ -18,6 +18,10 @@ #ifndef __ARM_KVM_PSCI_H__ #define __ARM_KVM_PSCI_H__
+#define KVM_ARM_PSCI_0_1 1 +#define KVM_ARM_PSCI_0_2 2
+int kvm_psci_version(struct kvm_vcpu *vcpu); bool kvm_psci_call(struct kvm_vcpu *vcpu);
#endif /* __ARM_KVM_PSCI_H__ */ diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h index c498b60..bf860e2 100644 --- a/arch/arm/include/uapi/asm/kvm.h +++ b/arch/arm/include/uapi/asm/kvm.h @@ -83,6 +83,7 @@ struct kvm_regs { #define KVM_VGIC_V2_CPU_SIZE 0x2000
#define KVM_ARM_VCPU_POWER_OFF 0 /* CPU is started in OFF state */ +#define KVM_ARM_VCPU_PSCI_0_2 1 /* CPU uses PSCI v0.2 */
struct kvm_vcpu_init { __u32 target; @@ -164,7 +165,7 @@ struct kvm_arch_memory_slot { /* Highest supported SPI, from VGIC_NR_IRQS */ #define KVM_ARM_IRQ_GIC_MAX 127
-/* PSCI interface */ +/* PSCI v0.1 interface */ #define KVM_PSCI_FN_BASE 0x95c1ba5e #define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n))
@@ -173,9 +174,41 @@ struct kvm_arch_memory_slot { #define KVM_PSCI_FN_CPU_ON KVM_PSCI_FN(2) #define KVM_PSCI_FN_MIGRATE KVM_PSCI_FN(3)
+/* PSCI v0.2 interface */ +#define KVM_PSCI_0_2_FN_BASE 0x84000000 +#define KVM_PSCI_0_2_FN(n) (KVM_PSCI_0_2_FN_BASE + (n)) +#define KVM_PSCI_0_2_FN64_BASE 0xC4000000 +#define KVM_PSCI_0_2_FN64(n) (KVM_PSCI_0_2_FN64_BASE + (n))
+#define KVM_PSCI_0_2_FN_PSCI_VERSION KVM_PSCI_0_2_FN(0) +#define KVM_PSCI_0_2_FN_CPU_SUSPEND KVM_PSCI_0_2_FN(1) +#define KVM_PSCI_0_2_FN_CPU_OFF KVM_PSCI_0_2_FN(2) +#define KVM_PSCI_0_2_FN_CPU_ON KVM_PSCI_0_2_FN(3) +#define KVM_PSCI_0_2_FN_AFFINITY_INFO KVM_PSCI_0_2_FN(4) +#define KVM_PSCI_0_2_FN_MIGRATE KVM_PSCI_0_2_FN(5) +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \
KVM_PSCI_0_2_FN(6)
+#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN(7)
+#define KVM_PSCI_0_2_FN_SYSTEM_OFF KVM_PSCI_0_2_FN(8) +#define KVM_PSCI_0_2_FN_SYSTEM_RESET KVM_PSCI_0_2_FN(9)
+#define KVM_PSCI_0_2_FN64_CPU_SUSPEND KVM_PSCI_0_2_FN64(1) +#define KVM_PSCI_0_2_FN64_CPU_ON KVM_PSCI_0_2_FN64(3) +#define KVM_PSCI_0_2_FN64_AFFINITY_INFO KVM_PSCI_0_2_FN64(4) +#define KVM_PSCI_0_2_FN64_MIGRATE KVM_PSCI_0_2_FN64(5) +#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN64(7)
+/* PSCI return values */ #define KVM_PSCI_RET_SUCCESS 0 #define KVM_PSCI_RET_NI ((unsigned long)-1) #define KVM_PSCI_RET_INVAL ((unsigned long)-2) #define KVM_PSCI_RET_DENIED ((unsigned long)-3) +#define KVM_PSCI_RET_ALREADY_ON ((unsigned long)-4) +#define KVM_PSCI_RET_ON_PENDING ((unsigned long)-5) +#define KVM_PSCI_RET_INTERNAL_FAILURE ((unsigned long)-6) +#define KVM_PSCI_RET_NOT_PRESENT ((unsigned long)-7) +#define KVM_PSCI_RET_DISABLED ((unsigned long)-8)
#endif /* __ARM_KVM_H__ */ diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 151eb91..e508125 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -193,6 +193,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: case KVM_CAP_ONE_REG: case KVM_CAP_ARM_PSCI:
case KVM_CAP_ARM_PSCI_0_2: r = 1; break; case KVM_CAP_COALESCED_MMIO:
diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index 448f60e..7fdc881 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -85,17 +85,57 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) return KVM_PSCI_RET_SUCCESS; }
-/**
- kvm_psci_call - handle PSCI call if r0 value is in range
- @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.
- */
-bool kvm_psci_call(struct kvm_vcpu *vcpu) +int kvm_psci_version(struct kvm_vcpu *vcpu) +{
if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
return KVM_ARM_PSCI_0_2;
return KVM_ARM_PSCI_0_1;
+}
+static bool kvm_psci_0_2_call(struct kvm_vcpu *vcpu) +{
unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0);
unsigned long val;
switch (psci_fn) {
case KVM_PSCI_0_2_FN_PSCI_VERSION:
/*
* Bits[31:16] = Major Version = 0
* Bits[15:0] = Minor Version = 2
*/
val = 2;
break;
case KVM_PSCI_0_2_FN_CPU_OFF:
kvm_psci_vcpu_off(vcpu);
val = KVM_PSCI_RET_SUCCESS;
break;
case KVM_PSCI_0_2_FN_CPU_ON:
case KVM_PSCI_0_2_FN64_CPU_ON:
val = kvm_psci_vcpu_on(vcpu);
break;
case KVM_PSCI_0_2_FN_CPU_SUSPEND:
case KVM_PSCI_0_2_FN_AFFINITY_INFO:
case KVM_PSCI_0_2_FN_MIGRATE:
case KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE:
case KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU:
case KVM_PSCI_0_2_FN_SYSTEM_OFF:
case KVM_PSCI_0_2_FN_SYSTEM_RESET:
case KVM_PSCI_0_2_FN64_CPU_SUSPEND:
case KVM_PSCI_0_2_FN64_AFFINITY_INFO:
case KVM_PSCI_0_2_FN64_MIGRATE:
case KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU:
val = KVM_PSCI_RET_NI;
break;
default:
return false;
}
*vcpu_reg(vcpu, 0) = val;
return true;
+}
+static bool kvm_psci_0_1_call(struct kvm_vcpu *vcpu) { unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); unsigned long val; @@ -112,7 +152,6 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu) case KVM_PSCI_FN_MIGRATE: val = KVM_PSCI_RET_NI; break;
default: return false; }
@@ -120,3 +159,25 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu) *vcpu_reg(vcpu, 0) = val; return true; }
+/**
- kvm_psci_call - handle PSCI call if r0 value is in range
- @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.
- */
+bool kvm_psci_call(struct kvm_vcpu *vcpu) +{
switch (kvm_psci_version(vcpu)) {
case KVM_ARM_PSCI_0_2:
return kvm_psci_0_2_call(vcpu);
case KVM_ARM_PSCI_0_1:
return kvm_psci_0_1_call(vcpu);
default:
return false;
};
+} diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 0a1d697..92242ce 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -39,7 +39,7 @@ #include <kvm/arm_vgic.h> #include <kvm/arm_arch_timer.h>
-#define KVM_VCPU_MAX_FEATURES 2 +#define KVM_VCPU_MAX_FEATURES 3
struct kvm_vcpu; int kvm_target_cpu(void); diff --git a/arch/arm64/include/asm/kvm_psci.h b/arch/arm64/include/asm/kvm_psci.h index e301a48..e25c658 100644 --- a/arch/arm64/include/asm/kvm_psci.h +++ b/arch/arm64/include/asm/kvm_psci.h @@ -18,6 +18,10 @@ #ifndef __ARM64_KVM_PSCI_H__ #define __ARM64_KVM_PSCI_H__
+#define KVM_ARM_PSCI_0_1 1 +#define KVM_ARM_PSCI_0_2 2
+int kvm_psci_version(struct kvm_vcpu *vcpu); bool kvm_psci_call(struct kvm_vcpu *vcpu);
#endif /* __ARM64_KVM_PSCI_H__ */ diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index d9f026b..b7555d3 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -77,6 +77,7 @@ struct kvm_regs {
#define KVM_ARM_VCPU_POWER_OFF 0 /* CPU is started in OFF state */ #define KVM_ARM_VCPU_EL1_32BIT 1 /* CPU running a 32bit VM */ +#define KVM_ARM_VCPU_PSCI_0_2 2 /* CPU uses PSCI v0.2 */
struct kvm_vcpu_init { __u32 target; @@ -150,7 +151,7 @@ struct kvm_arch_memory_slot { /* Highest supported SPI, from VGIC_NR_IRQS */ #define KVM_ARM_IRQ_GIC_MAX 127
-/* PSCI interface */ +/* PSCI v0.1 interface */ #define KVM_PSCI_FN_BASE 0x95c1ba5e #define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n))
@@ -159,10 +160,42 @@ struct kvm_arch_memory_slot { #define KVM_PSCI_FN_CPU_ON KVM_PSCI_FN(2) #define KVM_PSCI_FN_MIGRATE KVM_PSCI_FN(3)
+/* PSCI v0.2 interface */ +#define KVM_PSCI_0_2_FN_BASE 0x84000000 +#define KVM_PSCI_0_2_FN(n) (KVM_PSCI_0_2_FN_BASE + (n)) +#define KVM_PSCI_0_2_FN64_BASE 0xC4000000 +#define KVM_PSCI_0_2_FN64(n) (KVM_PSCI_0_2_FN64_BASE + (n))
+#define KVM_PSCI_0_2_FN_PSCI_VERSION KVM_PSCI_0_2_FN(0) +#define KVM_PSCI_0_2_FN_CPU_SUSPEND KVM_PSCI_0_2_FN(1) +#define KVM_PSCI_0_2_FN_CPU_OFF KVM_PSCI_0_2_FN(2) +#define KVM_PSCI_0_2_FN_CPU_ON KVM_PSCI_0_2_FN(3) +#define KVM_PSCI_0_2_FN_AFFINITY_INFO KVM_PSCI_0_2_FN(4) +#define KVM_PSCI_0_2_FN_MIGRATE KVM_PSCI_0_2_FN(5) +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \
KVM_PSCI_0_2_FN(6)
+#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN(7)
+#define KVM_PSCI_0_2_FN_SYSTEM_OFF KVM_PSCI_0_2_FN(8) +#define KVM_PSCI_0_2_FN_SYSTEM_RESET KVM_PSCI_0_2_FN(9)
+#define KVM_PSCI_0_2_FN64_CPU_SUSPEND KVM_PSCI_0_2_FN64(1) +#define KVM_PSCI_0_2_FN64_CPU_ON KVM_PSCI_0_2_FN64(3) +#define KVM_PSCI_0_2_FN64_AFFINITY_INFO KVM_PSCI_0_2_FN64(4) +#define KVM_PSCI_0_2_FN64_MIGRATE KVM_PSCI_0_2_FN64(5) +#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \
KVM_PSCI_0_2_FN64(7)
+/* PSCI return values */ #define KVM_PSCI_RET_SUCCESS 0 #define KVM_PSCI_RET_NI ((unsigned long)-1) #define KVM_PSCI_RET_INVAL ((unsigned long)-2) #define KVM_PSCI_RET_DENIED ((unsigned long)-3) +#define KVM_PSCI_RET_ALREADY_ON ((unsigned long)-4) +#define KVM_PSCI_RET_ON_PENDING ((unsigned long)-5) +#define KVM_PSCI_RET_INTERNAL_FAILURE ((unsigned long)-6) +#define KVM_PSCI_RET_NOT_PRESENT ((unsigned long)-7) +#define KVM_PSCI_RET_DISABLED ((unsigned long)-8)
#endif
-- 1.7.9.5
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I accidentally used wrong email-id for my last reply.
Please ignore this confidentiality notice.
Sorry for the noise.
Regards, Anup
kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm
On Mon, Feb 03, 2014 at 11:16:35AM +0000, Anup Patel wrote:
Hi Mark,
Hi Anup,
On Mon, Feb 3, 2014 at 4:24 PM, Mark Rutland mark.rutland@arm.com wrote:
On Thu, Jan 30, 2014 at 10:41:18AM +0000, Anup Patel wrote:
Currently, the in-kernel PSCI emulation provides PSCI v0.1 interface to VCPUs. This patch extends current in-kernel PSCI emulation to provide PSCI v0.2 interface to VCPUs.
By default, ARM/ARM64 KVM will always provide PSCI v0.1 interface for keeping the ABI backward-compatible.
To select PSCI v0.2 interface for VCPUs, the user space (i.e. QEMU or KVMTOOL) will have to set KVM_ARM_VCPU_PSCI_0_2 feature when doing VCPU init using KVM_ARM_VCPU_INIT ioctl.
I have an issue with this. PSCI 0.2 makes all but two functions (MIGRATE and MIGRATE_INFO_CPU_UP) mandatory, and hence not allowed to return NOT_SUPPORTED.
Additionally, for correct behaviour across a kexec in future, we'll require AFFINITY_INFO for PSCI 0.2+ systems to determint when a CPU is actually dead (and cannot affect the cache hierarchy). I'd very much like to make that a hard requirement to ensure correctness.
I would very much like to see at least trivial implementations of those mandatory functions, so that we don't need a KVM_ARM_VCPU_PSCI_REALLY_0_2 or similar in future. As it stands this series does not implement PSCI 0.2.
The intention behind this series was to provide a base implementation of PSCI v0.2 which can be extended by subsequent patches that implement other PSCI v0.2 functions.
I understand your intention, however I disagree with the approach.
This exposes the implementation to userspace before _mandatory_ functionality is present. This exposes a feature flag to userspace advertising functionality which is not present, and violates the PSCI 0.2 specification.
Userspace will check if the functionality is present, and then advertise it to whatever kernel it wants to run with KVM. However, as _mandatory_ functionality is missing, the guest cannot use the information, and must assume that the PSCI implementation violates the spec. This is broken.
The only things that this series does is change the set of IDs in use, and add PSCI_VERSION. Worse, PSCI_VERSION lies, because the mandatory functionality isn't present. Guests requiring PSCI 0.2 don't get everything they need, and existing supported guests work with the existing function IDs, so _nothing_ of value is added.
We also haven't got the PSCI 0.2 binding finalised, so no guest can even make use of the PSCI_VERSION call. The only apparent change of the series is therefore to rearrange some IDs. This holds _no_ value.
The only sane thing to do is to implement the mandatory functionality before exposing it.
The only way to make that work would be to later add more flags stating that we _really_ have PSCI 0.2 support, and then have userspace use that to figure out when to advertise PSCI 0.2 support to a guest. So _nothing_ can make use of the flag as it currently stands.
Thanks, Mark.
On Mon, Feb 03, 2014 at 10:54:09AM +0000, Mark Rutland wrote:
On Thu, Jan 30, 2014 at 10:41:18AM +0000, Anup Patel wrote:
Currently, the in-kernel PSCI emulation provides PSCI v0.1 interface to VCPUs. This patch extends current in-kernel PSCI emulation to provide PSCI v0.2 interface to VCPUs.
By default, ARM/ARM64 KVM will always provide PSCI v0.1 interface for keeping the ABI backward-compatible.
To select PSCI v0.2 interface for VCPUs, the user space (i.e. QEMU or KVMTOOL) will have to set KVM_ARM_VCPU_PSCI_0_2 feature when doing VCPU init using KVM_ARM_VCPU_INIT ioctl.
I have an issue with this. PSCI 0.2 makes all but two functions (MIGRATE and MIGRATE_INFO_CPU_UP) mandatory, and hence not allowed to return NOT_SUPPORTED.
Additionally, for correct behaviour across a kexec in future, we'll require AFFINITY_INFO for PSCI 0.2+ systems to determint when a CPU is actually dead (and cannot affect the cache hierarchy). I'd very much like to make that a hard requirement to ensure correctness.
I would very much like to see at least trivial implementations of those mandatory functions, so that we don't need a KVM_ARM_VCPU_PSCI_REALLY_0_2 or similar in future. As it stands this series does not implement PSCI 0.2.
I didn't realize that PSCI 0.2 mandates more functions, that should clearly be implemented first, and the patch series should also be ordered with first supporting the implementation and then finally exposing the functionality to user space.
Thanks, -Christoffer
We have in-kernel emulation of PSCI v0.2 in KVM ARM/ARM64. To provide PSCI v0.2 interface to VCPUs, we have to enable KVM_ARM_VCPU_PSCI_0_2 feature when doing KVM_ARM_VCPU_INIT ioctl.
The patch updates documentation of KVM_ARM_VCPU_INIT ioctl to provide info regarding KVM_ARM_VCPU_PSCI_0_2 feature.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org --- Documentation/virtual/kvm/api.txt | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index aad3244..f842588 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2346,6 +2346,8 @@ Possible features: Depends on KVM_CAP_ARM_PSCI. - KVM_ARM_VCPU_EL1_32BIT: Starts the CPU in a 32bit mode. Depends on KVM_CAP_ARM_EL1_32BIT (arm64 only). + - KVM_ARM_VCPU_PSCI_0_2: Emulate PSCI v0.2 for the CPU. + Depends on KVM_CAP_ARM_PSCI_0_2.
4.83 KVM_ARM_PREFERRED_TARGET
On Thu, Jan 30, 2014 at 04:11:19PM +0530, Anup Patel wrote:
We have in-kernel emulation of PSCI v0.2 in KVM ARM/ARM64. To provide PSCI v0.2 interface to VCPUs, we have to enable KVM_ARM_VCPU_PSCI_0_2 feature when doing KVM_ARM_VCPU_INIT ioctl.
The patch updates documentation of KVM_ARM_VCPU_INIT ioctl to provide info regarding KVM_ARM_VCPU_PSCI_0_2 feature.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org
Documentation/virtual/kvm/api.txt | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index aad3244..f842588 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2346,6 +2346,8 @@ Possible features: Depends on KVM_CAP_ARM_PSCI.
- KVM_ARM_VCPU_EL1_32BIT: Starts the CPU in a 32bit mode. Depends on KVM_CAP_ARM_EL1_32BIT (arm64 only).
- KVM_ARM_VCPU_PSCI_0_2: Emulate PSCI v0.2 for the CPU.
Depends on KVM_CAP_ARM_PSCI_0_2.
4.83 KVM_ARM_PREFERRED_TARGET -- 1.7.9.5
Acked-by: Christoffer Dall christoffer.dall@linaro.org
linaro-kernel@lists.linaro.org