From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoffer Dall Subject: Re: [PATCH RFC 7/7] ARM64: KVM: Add user set handler for id_aa64mmfr0_el1 Date: Thu, 9 Mar 2017 04:52:18 -0800 Message-ID: <20170309125218.GD114809@lvm> References: <1484559214-2248-1-git-send-email-zhaoshenglong@huawei.com> <1484559214-2248-8-git-send-email-zhaoshenglong@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 3495A40AE8 for ; Thu, 9 Mar 2017 07:50:58 -0500 (EST) Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id o2hD2tg4b-l2 for ; Thu, 9 Mar 2017 07:50:56 -0500 (EST) Received: from mail-wr0-f175.google.com (mail-wr0-f175.google.com [209.85.128.175]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 8D6E340A66 for ; Thu, 9 Mar 2017 07:50:56 -0500 (EST) Received: by mail-wr0-f175.google.com with SMTP id g10so44365964wrg.2 for ; Thu, 09 Mar 2017 04:52:21 -0800 (PST) Content-Disposition: inline In-Reply-To: <1484559214-2248-8-git-send-email-zhaoshenglong@huawei.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: Shannon Zhao Cc: marc.zyngier@arm.com, qemu-arm@nongnu.org, kvmarm@lists.cs.columbia.edu, wu.wubin@huawei.com List-Id: kvmarm@lists.cs.columbia.edu On Mon, Jan 16, 2017 at 05:33:34PM +0800, Shannon Zhao wrote: > From: Shannon Zhao > > Check if the configuration is fine. This commit message really needs some love and attention. > > Signed-off-by: Shannon Zhao > --- > arch/arm64/kvm/sys_regs.c | 32 +++++++++++++++++++++++++++++++- > 1 file changed, 31 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c > index f613e29..9763b79 100644 > --- a/arch/arm64/kvm/sys_regs.c > +++ b/arch/arm64/kvm/sys_regs.c > @@ -1493,6 +1493,35 @@ static bool access_id_reg(struct kvm_vcpu *vcpu, > return true; > } > > +static int set_id_aa64mmfr0_el1(struct kvm_vcpu *vcpu, > + const struct sys_reg_desc *rd, > + const struct kvm_one_reg *reg, > + void __user *uaddr) > +{ > + u64 val, id_aa64mmfr0; > + > + if (copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id)) != 0) > + return -EFAULT; > + > + asm volatile("mrs %0, id_aa64mmfr0_el1\n" : "=r" (id_aa64mmfr0)); Doesn't the kernel have an abstraction for this already or a cached value? > + > + if ((val & GENMASK(3, 0)) > (id_aa64mmfr0 & GENMASK(3, 0)) || > + (val & GENMASK(7, 4)) > (id_aa64mmfr0 & GENMASK(7, 4)) || > + (val & GENMASK(11, 8)) > (id_aa64mmfr0 & GENMASK(11, 8)) || > + (val & GENMASK(15, 12)) > (id_aa64mmfr0 & GENMASK(15, 12)) || > + (val & GENMASK(19, 16)) > (id_aa64mmfr0 & GENMASK(19, 16)) || > + (val & GENMASK(23, 20)) > (id_aa64mmfr0 & GENMASK(23, 20)) || > + (val & GENMASK(27, 24)) < (id_aa64mmfr0 & GENMASK(27, 24)) || > + (val & GENMASK(31, 28)) < (id_aa64mmfr0 & GENMASK(31, 28))) { > + kvm_err("Wrong memory translation granule size/Physical Address range\n"); > + return -EINVAL; > + } This really needs some explanation as to what it's checking and what the logic is. > + > + vcpu_id_sys_reg(vcpu, rd->reg) = val & GENMASK(31, 0); > + > + return 0; > +} > + > static struct sys_reg_desc invariant_sys_regs[] = { > { Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0000), Op2(0b000), > access_id_reg, get_midr_el1, MIDR_EL1 }, > @@ -1549,7 +1578,8 @@ static struct sys_reg_desc invariant_sys_regs[] = { > { Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0110), Op2(0b001), > access_id_reg, get_id_aa64isar1_el1, ID_AA64ISAR1_EL1 }, > { Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0111), Op2(0b000), > - access_id_reg, get_id_aa64mmfr0_el1, ID_AA64MMFR0_EL1 }, > + access_id_reg, get_id_aa64mmfr0_el1, ID_AA64MMFR0_EL1, > + 0, NULL, set_id_aa64mmfr0_el1 }, > { Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0111), Op2(0b001), > access_id_reg, get_id_aa64mmfr1_el1, ID_AA64MMFR1_EL1 }, > { Op0(0b11), Op1(0b001), CRn(0b0000), CRm(0b0000), Op2(0b001), > -- > 2.0.4 > > Thanks, -Christoffer