linux-kernel - Re: [PATCHv2] x86 trace: Fix page fault tracing bug

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: <5310B54F.3000709@zytor.com>
Date:	Fri, 28 Feb 2014 08:11:59 -0800
From:	"H. Peter Anvin" <hpa@...or.com>
To:	Jiri Olsa <jolsa@...hat.com>, Peter Zijlstra <peterz@...radead.org>
CC:	linux-kernel@...r.kernel.org, Paul Mackerras <paulus@...ba.org>,
	Ingo Molnar <mingo@...hat.com>,
	Arnaldo Carvalho de Melo <acme@...stprotocols.net>,
	Seiji Aguchi <seiji.aguchi@....com>,
	Steven Rostedt <rostedt@...dmis.org>,
	Vince Weaver <vincent.weaver@...ne.edu>
Subject: Re: [PATCHv2] x86 trace: Fix page fault tracing bug

On 02/28/2014 08:05 AM, Jiri Olsa wrote:
> On Fri, Feb 28, 2014 at 04:47:08PM +0100, Peter Zijlstra wrote:
>> On Fri, Feb 28, 2014 at 04:33:40PM +0100, Jiri Olsa wrote:
>>
>> While I like the idea of just pushing up the CR2 read; the below does
>> the read too late still, exception_enter() also has a tracepoint in.
> 
> please check v2, thanks

Is there any way something could come in even earlier (perhaps via
__fentry__)?

If so, do we need to hoist the reading of %cr2 all the way into assembly
or something else?

	-hpa

--
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/