Re: [PATCH v5 15/22] RISC-V: KVM: Improve firmware counter read function

Andrew Jones
2024-04-05T12:12:59Z

On Wed, Apr 03, 2024 at 01:04:44AM -0700, Atish Patra wrote:
> Rename the function to indicate that it is meant for firmware
> counter read. While at it, add a range sanity check for it as
> well.
>
> Signed-off-by: Atish Patra <atishp@rivosinc.com>
> ---
> arch/riscv/include/asm/kvm_vcpu_pmu.h | 2 +-
> arch/riscv/kvm/vcpu_pmu.c | 7 ++++++-
> arch/riscv/kvm/vcpu_sbi_pmu.c | 2 +-
> 3 files changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/arch/riscv/include/asm/kvm_vcpu_pmu.h b/arch/riscv/include/asm/kvm_vcpu_pmu.h
> index 55861b5d3382..fa0f535bbbf0 100644
> --- a/arch/riscv/include/asm/kvm_vcpu_pmu.h
> +++ b/arch/riscv/include/asm/kvm_vcpu_pmu.h
> @@ -89,7 +89,7 @@ int kvm_riscv_vcpu_pmu_ctr_cfg_match(struct kvm_vcpu *vcpu, unsigned long ctr_ba
> unsigned long ctr_mask, unsigned long flags,
> unsigned long eidx, u64 evtdata,
> struct kvm_vcpu_sbi_return *retdata);
> -int kvm_riscv_vcpu_pmu_ctr_read(struct kvm_vcpu *vcpu, unsigned long cidx,
> +int kvm_riscv_vcpu_pmu_fw_ctr_read(struct kvm_vcpu *vcpu, unsigned long cidx,
> struct kvm_vcpu_sbi_return *retdata);
> int kvm_riscv_vcpu_pmu_fw_ctr_read_hi(struct kvm_vcpu *vcpu, unsigned long cidx,
> struct kvm_vcpu_sbi_return *retdata);
> diff --git a/arch/riscv/kvm/vcpu_pmu.c b/arch/riscv/kvm/vcpu_pmu.c
> index ff326152eeff..94efa88d054d 100644
> --- a/arch/riscv/kvm/vcpu_pmu.c
> +++ b/arch/riscv/kvm/vcpu_pmu.c
> @@ -235,6 +235,11 @@ static int pmu_ctr_read(struct kvm_vcpu *vcpu, unsigned long cidx,
> u64 enabled, running;
> int fevent_code;
>
> + if (cidx >= kvm_pmu_num_counters(kvpmu) || cidx == 1) {
> + pr_warn("Invalid counter id [%ld] during read\n", cidx);
> + return -EINVAL;
> + }
> +
> pmc = &kvpmu->pmc[cidx];
>
> if (pmc->cinfo.type == SBI_PMU_CTR_TYPE_FW) {
> @@ -747,7 +752,7 @@ int kvm_riscv_vcpu_pmu_fw_ctr_read_hi(struct kvm_vcpu *vcpu, unsigned long cidx,
> return 0;
> }
>
> -int kvm_riscv_vcpu_pmu_ctr_read(struct kvm_vcpu *vcpu, unsigned long cidx,
> +int kvm_riscv_vcpu_pmu_fw_ctr_read(struct kvm_vcpu *vcpu, unsigned long cidx,
> struct kvm_vcpu_sbi_return *retdata)
> {
> int ret;
> diff --git a/arch/riscv/kvm/vcpu_sbi_pmu.c b/arch/riscv/kvm/vcpu_sbi_pmu.c
> index cf111de51bdb..e4be34e03e83 100644
> --- a/arch/riscv/kvm/vcpu_sbi_pmu.c
> +++ b/arch/riscv/kvm/vcpu_sbi_pmu.c
> @@ -62,7 +62,7 @@ static int kvm_sbi_ext_pmu_handler(struct kvm_vcpu *vcpu, struct kvm_run *run,
> ret = kvm_riscv_vcpu_pmu_ctr_stop(vcpu, cp->a0, cp->a1, cp->a2, retdata);
> break;
> case SBI_EXT_PMU_COUNTER_FW_READ:
> - ret = kvm_riscv_vcpu_pmu_ctr_read(vcpu, cp->a0, retdata);
> + ret = kvm_riscv_vcpu_pmu_fw_ctr_read(vcpu, cp->a0, retdata);
> break;
> case SBI_EXT_PMU_COUNTER_FW_READ_HI:
> if (IS_ENABLED(CONFIG_32BIT))
> --
> 2.34.1
>

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>