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Subject: Re: [RFC PATCH 06/16] RISC-V: KVM: Implement
 KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls
From:   Paolo Bonzini <pbonzini@redhat.com>
To:     Anup Patel <Anup.Patel@wdc.com>,
        Palmer Dabbelt <palmer@sifive.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Radim K <rkrcmar@redhat.com>
Cc:     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>,
        Anup Patel <anup@brainfault.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>
References: <20190729115544.17895-1-anup.patel@wdc.com>
 <20190729115544.17895-7-anup.patel@wdc.com>
 <3caa5b31-f5ed-98cd-2bdf-88d8cb837919@redhat.com>
Message-ID: <536673cd-3b84-4e56-6042-de73a536653f@redhat.com>
Date:   Tue, 30 Jul 2019 11:35:54 +0200
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On 30/07/19 10:43, Paolo Bonzini wrote:
> On 29/07/19 13:56, Anup Patel wrote:
>> The PC register represents program counter whereas the MODE
>> register represent VCPU privilege mode (i.e. S/U-mode).
>>
> Is there any reason to include this pseudo-register instead of allowing
> SSTATUS access directly in this patch (and perhaps also SEPC)?

Nevermind, I was confused - the current MODE is indeed not accessible as
a "real" CSR in RISC-V.

Still, I would prefer all the VS CSRs to be accessible via the get/set
reg ioctls.

Paolo