linux-kernel - RE: [PATCH v5 2/3] x86, mpx: hook #BR exception handler to allocate bound tables

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: <9E0BE1322F2F2246BD820DA9FC397ADE0151FC9E@SHSMSX102.ccr.corp.intel.com>
Date:	Tue, 25 Feb 2014 13:34:24 +0000
From:	"Ren, Qiaowei" <qiaowei.ren@...el.com>
To:	"H. Peter Anvin" <hpa@...or.com>,
	"Hansen, Dave" <dave.hansen@...el.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>
CC:	"x86@...nel.org" <x86@...nel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: [PATCH v5 2/3] x86, mpx: hook #BR exception handler to allocate
 bound tables


> -----Original Message-----
> From: H. Peter Anvin [mailto:hpa@...or.com]
> Sent: Tuesday, February 25, 2014 1:52 AM
> To: Hansen, Dave; Ren, Qiaowei; Thomas Gleixner; Ingo Molnar
> Cc: x86@...nel.org; linux-kernel@...r.kernel.org
> Subject: Re: [PATCH v5 2/3] x86, mpx: hook #BR exception handler to allocate
> bound tables
> 
> On 02/24/2014 09:27 AM, Dave Hansen wrote:
> >
> > Can you talk a little bit about what the design is here?  Why does the
> > kernel have to do the allocation of the virtual address space?  Does
> > it really need to MAP_POPULATE?  bt_size looks like 4MB, and that's an
> > awful lot of memory to eat up at once.  Shouldn't we just let the
> > kernel demand-fault this like everything else?
> >
> 
> MAP_POPULATE definitely seems like the wrong thing.
> 
Oh. This option should be removed.

Thanks,
Qiaowei
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/