From mboxrd@z Thu Jan  1 00:00:00 1970
From: Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>
Subject: Re: [PATCH 3/5] KVM: add KVM_USER_EXIT vm ioctl for userspace exit
Date: Wed, 5 Aug 2015 15:48:22 +0200
Message-ID: <20150805134821.GA1481@potion.brq.redhat.com>
References: <1438780877-31838-1-git-send-email-rkrcmar@redhat.com>
 <1438780877-31838-4-git-send-email-rkrcmar@redhat.com>
 <55C20FD2.8020607@redhat.com>
 <20150805133442.GA31952@potion.brq.redhat.com>
 <55C211EB.2030704@redhat.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: QUOTED-PRINTABLE
Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
To: Paolo Bonzini <pbonzini@redhat.com>
Return-path: <linux-kernel-owner@vger.kernel.org>
Content-Disposition: inline
In-Reply-To: <55C211EB.2030704@redhat.com>
Sender: linux-kernel-owner@vger.kernel.org
List-Id: kvm.vger.kernel.org

2015-08-05 15:38+0200, Paolo Bonzini:
> On 05/08/2015 15:34, Radim Kr=C4=8Dm=C3=A1=C5=99 wrote:
>> vcpu ioctl should only be issued by the vcpu thread so it would
>> significantly limit use.
>=20
> That's a general limitation, but you can lift it for particular ioctl=
s.
>=20
> See in particular this:
>=20
> #if defined(CONFIG_S390) || defined(CONFIG_PPC) || defined(CONFIG_MIP=
S)
>         /*
>          * Special cases: vcpu ioctls that are asynchronous to vcpu e=
xecution,
>          * so vcpu_load() would break it.
>          */
>         if (ioctl =3D=3D KVM_S390_INTERRUPT || ioctl =3D=3D KVM_S390_=
IRQ || ioctl =3D=3D KVM_INTERRUPT)
>                 return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
> #endif
>=20
> You can add an "if (ioctl =3D=3D KVM_USER_EXIT)" before.

Thanks, it looks to be safe, I'll put it in v2.