diff options
| -rw-r--r-- | Documentation/virt/kvm/api.txt | 9 | ||||
| -rw-r--r-- | arch/arm64/include/uapi/asm/kvm.h | 12 |
2 files changed, 19 insertions, 2 deletions
diff --git a/Documentation/virt/kvm/api.txt b/Documentation/virt/kvm/api.txt index ebb37b34dcfc..3a0c819c3573 100644 --- a/Documentation/virt/kvm/api.txt +++ b/Documentation/virt/kvm/api.txt @@ -2196,6 +2196,15 @@ arm64 CCSIDR registers are demultiplexed by CSSELR value: arm64 system registers have the following id bit patterns: 0x6030 0000 0013 <op0:2> <op1:3> <crn:4> <crm:4> <op2:3> +WARNING: + Two system register IDs do not follow the specified pattern. These + are KVM_REG_ARM_TIMER_CVAL and KVM_REG_ARM_TIMER_CNT, which map to + system registers CNTV_CVAL_EL0 and CNTVCT_EL0 respectively. These + two had their values accidentally swapped, which means TIMER_CVAL is + derived from the register encoding for CNTVCT_EL0 and TIMER_CNT is + derived from the register encoding for CNTV_CVAL_EL0. As this is + API, it must remain this way. + arm64 firmware pseudo-registers have the following bit pattern: 0x6030 0000 0014 <regno:16> diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index 820e5751ada7..ba85bb23f060 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -220,10 +220,18 @@ struct kvm_vcpu_events { #define KVM_REG_ARM_PTIMER_CVAL ARM64_SYS_REG(3, 3, 14, 2, 2) #define KVM_REG_ARM_PTIMER_CNT ARM64_SYS_REG(3, 3, 14, 0, 1) -/* EL0 Virtual Timer Registers */ +/* + * EL0 Virtual Timer Registers + * + * WARNING: + * KVM_REG_ARM_TIMER_CVAL and KVM_REG_ARM_TIMER_CNT are not defined + * with the appropriate register encodings. Their values have been + * accidentally swapped. As this is set API, the definitions here + * must be used, rather than ones derived from the encodings. + */ #define KVM_REG_ARM_TIMER_CTL ARM64_SYS_REG(3, 3, 14, 3, 1) -#define KVM_REG_ARM_TIMER_CNT ARM64_SYS_REG(3, 3, 14, 3, 2) #define KVM_REG_ARM_TIMER_CVAL ARM64_SYS_REG(3, 3, 14, 0, 2) +#define KVM_REG_ARM_TIMER_CNT ARM64_SYS_REG(3, 3, 14, 3, 2) /* KVM-as-firmware specific pseudo-registers */ #define KVM_REG_ARM_FW (0x0014 << KVM_REG_ARM_COPROC_SHIFT) |