linux-kernel - Re: [PATCH 1/3] arm/arm64/xen: use C inlines for privcmd

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]

Date:   Wed, 4 Dec 2019 12:58:20 -0500
From:   Pavel Tatashin <pasha.tatashin@...een.com>
To:     Julien Grall <julien@....org>
Cc:     James Morris <jmorris@...ei.org>, Sasha Levin <sashal@...nel.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Catalin Marinas <catalin.marinas@....com>,
        Will Deacon <will@...nel.org>, steve.capper@....com,
        Linux ARM <linux-arm-kernel@...ts.infradead.org>,
        Marc Zyngier <marc.zyngier@....com>,
        James Morse <james.morse@....com>,
        Vladimir Murzin <vladimir.murzin@....com>,
        Mark Rutland <mark.rutland@....com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        allison@...utok.net, info@...ux.net, alexios.zavras@...el.com,
        Stefano Stabellini <sstabellini@...nel.org>,
        boris.ostrovsky@...cle.com, jgross@...e.com,
        Stefan Agner <stefan@...er.ch>,
        Masahiro Yamada <yamada.masahiro@...ionext.com>,
        xen-devel@...ts.xenproject.org,
        Russell King - ARM Linux admin <linux@...linux.org.uk>
Subject: Re: [PATCH 1/3] arm/arm64/xen: use C inlines for privcmd_call

On Fri, Nov 29, 2019 at 10:05 AM Julien Grall <julien@....org> wrote:
>
> Hi,
>
> On 27/11/2019 18:44, Pavel Tatashin wrote:
> > diff --git a/arch/arm64/include/asm/xen/hypercall.h b/arch/arm64/include/asm/xen/hypercall.h
> > index 3522cbaed316..1a74fb28607f 100644
> > --- a/arch/arm64/include/asm/xen/hypercall.h
> > +++ b/arch/arm64/include/asm/xen/hypercall.h
> > @@ -1 +1,29 @@
> > +#ifndef _ASM_ARM64_XEN_HYPERCALL_H
> > +#define _ASM_ARM64_XEN_HYPERCALL_H
> >   #include <xen/arm/hypercall.h>
> > +#include <linux/uaccess.h>
> > +
> > +static inline long privcmd_call(unsigned int call, unsigned long a1,
> > +                             unsigned long a2, unsigned long a3,
> > +                             unsigned long a4, unsigned long a5)
>
> I realize that privcmd_call is the only hypercall using Software PAN at
> the moment. However, dm_op needs the same as hypercall will be issued
> from userspace as well.

The clean-up I am working on now is specific to moving current PAN
useage to C wraps. Once dm_op requires to use PAN it will need to be
used the C variants, because ASM versions are going to be removed by
this series.

>
> So I was wondering whether we should create a generic function (e.g.
> do_xen_hypercall() or do_xen_user_hypercall()) to cover the two hypercalls?
>
> > diff --git a/include/xen/arm/hypercall.h b/include/xen/arm/hypercall.h
> > index b40485e54d80..624c8ad7e42a 100644
> > --- a/include/xen/arm/hypercall.h
> > +++ b/include/xen/arm/hypercall.h
> > @@ -30,8 +30,8 @@
> >    * IN THE SOFTWARE.
> >    */
> >
> > -#ifndef _ASM_ARM_XEN_HYPERCALL_H
> > -#define _ASM_ARM_XEN_HYPERCALL_H
> > +#ifndef _ARM_XEN_HYPERCALL_H
> > +#define _ARM_XEN_HYPERCALL_H
>
> This change feels a bit out of context. Could you split it in a separate
> patch?

Makes sense, I am splitting this into a separate patch.

Thank you,
Pasha