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AJvYcCVQHPpUobhU0L8Ssr23mjA+6o8hMMZEnEPFC1tkFpJnO7wtjL5kCjyvnyvZrueIb5qBOtI7WxFYkjpRR1noQ0zJ8nzV2F8u5J5XlbI56s4= X-Gm-Message-State: AOJu0YzTye/5Mxm9zCeNI1nclkHRSwIGFkwLi1BZSDCPg8jleWycRK+x dlspFlfa2NXL9eJXKpIkgGdC622zLFzVZEtOpHgbwLQxunzzqd+MLaFMUSUBblY= X-Google-Smtp-Source: AGHT+IFuxivVAucFqLYqwANgIIbEmyPV0tNMGWLxqaH8776sBq/Go9KZec7LTwKbbmPafjRvAwUZ5w== X-Received: by 2002:a17:903:22ca:b0:1e5:2ba9:a667 with SMTP id y10-20020a17090322ca00b001e52ba9a667mr4212130plg.3.1713570483020; Fri, 19 Apr 2024 16:48:03 -0700 (PDT) Received: from atishp.ba.rivosinc.com ([64.71.180.162]) by smtp.gmail.com with ESMTPSA id w17-20020a170902d11100b001e42f215f33sm3924017plw.85.2024.04.19.16.48.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Apr 2024 16:48:02 -0700 (PDT) From: Atish Patra To: linux-kernel@vger.kernel.org Cc: Atish Patra , Andrew Jones , Ajay Kaher , Albert Ou , Alexandre Ghiti , Anup Patel , samuel.holland@sifive.com, Conor Dooley , Juergen Gross , kvm-riscv@lists.infradead.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-riscv@lists.infradead.org, Mark Rutland , Palmer Dabbelt , Paolo Bonzini , Paul Walmsley , Shuah Khan , virtualization@lists.linux.dev, Will Deacon , x86@kernel.org Subject: [PATCH v8 10/24] RISC-V: KVM: Fix the initial sample period value Date: Sat, 20 Apr 2024 08:17:26 -0700 Message-Id: <20240420151741.962500-11-atishp@rivosinc.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240420151741.962500-1-atishp@rivosinc.com> References: <20240420151741.962500-1-atishp@rivosinc.com> Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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 Signed-off-by: Atish Patra --- 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