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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAAhSdy34VhGY3v9h3cw167MafKHOF1dL6zqB7Wi6A9Z4fo7ZNg@mail.gmail.com>
Date: Mon, 22 Apr 2024 10:54:52 +0530
From: Anup Patel <anup@...infault.org>
To: Atish Patra <atishp@...osinc.com>
Cc: linux-kernel@...r.kernel.org, Andrew Jones <ajones@...tanamicro.com>, 
	Ajay Kaher <ajay.kaher@...adcom.com>, Albert Ou <aou@...s.berkeley.edu>, 
	Alexandre Ghiti <alexghiti@...osinc.com>, samuel.holland@...ive.com, 
	Conor Dooley <conor.dooley@...rochip.com>, Juergen Gross <jgross@...e.com>, 
	kvm-riscv@...ts.infradead.org, kvm@...r.kernel.org, 
	linux-kselftest@...r.kernel.org, linux-riscv@...ts.infradead.org, 
	Mark Rutland <mark.rutland@....com>, Palmer Dabbelt <palmer@...belt.com>, 
	Paolo Bonzini <pbonzini@...hat.com>, Paul Walmsley <paul.walmsley@...ive.com>, 
	Shuah Khan <shuah@...nel.org>, virtualization@...ts.linux.dev, 
	Will Deacon <will@...nel.org>, x86@...nel.org
Subject: Re: [PATCH v8 10/24] RISC-V: KVM: Fix the initial sample period value

On Sat, Apr 20, 2024 at 5:18 AM Atish Patra <atishp@...osinc.com> wrote:
>
> 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@...tanamicro.com>
> Signed-off-by: Atish Patra <atishp@...osinc.com>

LGTM.

Reviewed-by: Anup Patel <anup@...infault.org>

Regards,
Anup

> ---
>  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
>