[PATCH v8 10/24] RISC-V: KVM: Fix the initial sample period value

Atish Patra atishp at rivosinc.com
Sat Apr 20 08:17:26 PDT 2024


The initial sample period value when counter value is not assigned
should be set to maximum value supported by the counter width.
Otherwise, it may result in spurious interrupts.

Reviewed-by: Andrew Jones <ajones at ventanamicro.com>
Signed-off-by: Atish Patra <atishp at rivosinc.com>
---
 arch/riscv/kvm/vcpu_pmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/kvm/vcpu_pmu.c b/arch/riscv/kvm/vcpu_pmu.c
index 86391a5061dd..cee1b9ca4ec4 100644
--- a/arch/riscv/kvm/vcpu_pmu.c
+++ b/arch/riscv/kvm/vcpu_pmu.c
@@ -39,7 +39,7 @@ static u64 kvm_pmu_get_sample_period(struct kvm_pmc *pmc)
 	u64 sample_period;
 
 	if (!pmc->counter_val)
-		sample_period = counter_val_mask + 1;
+		sample_period = counter_val_mask;
 	else
 		sample_period = (-pmc->counter_val) & counter_val_mask;
 
-- 
2.34.1




More information about the linux-riscv mailing list