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From:   Anup Patel <anup@brainfault.org>
Date:   Mon, 5 Aug 2019 17:43:27 +0530
Message-ID: <CAAhSdy1tfL6uLeXANzuZLidg9E-YTUfDQU7zxhBz1_AH+BvZaA@mail.gmail.com>
Subject: Re: [RFC PATCH v2 07/19] RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG
 ioctls
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     Christian Borntraeger <borntraeger@de.ibm.com>,
        Anup Patel <Anup.Patel@wdc.com>,
        Palmer Dabbelt <palmer@sifive.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Radim K <rkrcmar@redhat.com>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Atish Patra <Atish.Patra@wdc.com>,
        Alistair Francis <Alistair.Francis@wdc.com>,
        Damien Le Moal <Damien.LeMoal@wdc.com>,
        Christoph Hellwig <hch@infradead.org>,
        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        "linux-riscv@lists.infradead.org" <linux-riscv@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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On Mon, Aug 5, 2019 at 5:31 PM Paolo Bonzini <pbonzini@redhat.com> wrote:
>
> On 05/08/19 13:56, Anup Patel wrote:
> > We will certainly explore sync_regs interface. Reducing exits to user-space
> > will definitely help.
>
> sync_regs does not reduce exits to userspace, it reduces ioctls from
> userspace but there is a real benefit only if userspace actually makes
> many syscalls for each vmexit.

Thanks, got it.

Regards,
Anup