linux-kernel - Re: [PATCH v2 07/18] nitro_enclaves: Init misc device providing the ioctl interface

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]

Message-ID: <20200526064243.GB2580410@kroah.com>
Date:   Tue, 26 May 2020 08:42:43 +0200
From:   Greg KH <gregkh@...uxfoundation.org>
To:     "Paraschiv, Andra-Irina" <andraprs@...zon.com>
Cc:     linux-kernel@...r.kernel.org,
        Anthony Liguori <aliguori@...zon.com>,
        Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Colm MacCarthaigh <colmmacc@...zon.com>,
        Bjoern Doebel <doebel@...zon.de>,
        David Woodhouse <dwmw@...zon.co.uk>,
        Frank van der Linden <fllinden@...zon.com>,
        Alexander Graf <graf@...zon.de>,
        Martin Pohlack <mpohlack@...zon.de>,
        Matt Wilson <msw@...zon.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Balbir Singh <sblbir@...zon.com>,
        Stefano Garzarella <sgarzare@...hat.com>,
        Stefan Hajnoczi <stefanha@...hat.com>,
        Stewart Smith <trawets@...zon.com>,
        Uwe Dannowski <uwed@...zon.de>, kvm@...r.kernel.org,
        ne-devel-upstream@...zon.com
Subject: Re: [PATCH v2 07/18] nitro_enclaves: Init misc device providing the
 ioctl interface

On Mon, May 25, 2020 at 11:49:50PM +0300, Paraschiv, Andra-Irina wrote:
> 
> 
> On 22/05/2020 10:07, Greg KH wrote:
> > On Fri, May 22, 2020 at 09:29:35AM +0300, Andra Paraschiv wrote:
> > > +static char *ne_cpus;
> > > +module_param(ne_cpus, charp, 0644);
> > > +MODULE_PARM_DESC(ne_cpus, "<cpu-list> - CPU pool used for Nitro Enclaves");
> > This is not the 1990's, don't use module parameters if you can help it.
> > Why is this needed, and where is it documented?
> 
> This is a CPU pool that can be set by the root user and that includes CPUs
> set aside to be used for the enclave(s) setup; these CPUs are offlined. From
> this CPU pool, the kernel logic chooses the CPUs that are set for the
> created enclave(s).
> 
> The cpu-list format is matching the same that is documented here:
> 
> https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html
> 
> I've also thought of having a sysfs entry for the setup of this enclave CPU
> pool.

Ok, but again, do not use a module parameter, they are hard to use,
tough to document, and global.  All things we moved away from a long
time ago.  Please use something else for this (sysfs, configfs, etc.)
instead.

thanks,

greg k-h