RISC-V: KVM: Fix to allow hpmcounter31 from the guest

[ Upstream commit 5aa0929 ]

The csr_fun defines a count parameter which defines the total number
CSRs emulated in KVM starting from the base. This value should be
equal to total number of counters possible for trap/emulation (32).

Fixes: a9ac6c3 ("RISC-V: KVM: Implement trap & emulate for hpmcounters")
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20240816-kvm_pmu_fixes-v1-2-cdfce386dd93@rivosinc.com
Signed-off-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: atishp04

arch/riscv/include/asm/kvm_vcpu_pmu.h

@@ -58,11 +58,11 @@ struct kvm_pmu {
 
 #if defined(CONFIG_32BIT)
 #define KVM_RISCV_VCPU_HPMCOUNTER_CSR_FUNCS \
-{.base = CSR_CYCLEH,	.count = 31,	.func = kvm_riscv_vcpu_pmu_read_hpm }, \
-{.base = CSR_CYCLE,	.count = 31,	.func = kvm_riscv_vcpu_pmu_read_hpm },
+{.base = CSR_CYCLEH,	.count = 32,	.func = kvm_riscv_vcpu_pmu_read_hpm }, \
+{.base = CSR_CYCLE,	.count = 32,	.func = kvm_riscv_vcpu_pmu_read_hpm },
 #else
 #define KVM_RISCV_VCPU_HPMCOUNTER_CSR_FUNCS \
-{.base = CSR_CYCLE,	.count = 31,	.func = kvm_riscv_vcpu_pmu_read_hpm },
+{.base = CSR_CYCLE,	.count = 32,	.func = kvm_riscv_vcpu_pmu_read_hpm },
 #endif
 
 int kvm_riscv_vcpu_pmu_incr_fw(struct kvm_vcpu *vcpu, unsigned long fid);