lkml.org 
[lkml]   [2014]   [Oct]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH v5 12/20] x86: perf: intel_pt: Intel PT PMU driver
Date
Peter Zijlstra <peterz@infradead.org> writes:

> On Mon, Oct 13, 2014 at 04:45:40PM +0300, Alexander Shishkin wrote:
>> +static bool pt_event_valid(struct perf_event *event)
>> +{
>> + u64 config = event->attr.config;
>> +
>> + /* admin can set any packet generation parameters */
>> + if (capable(CAP_SYS_ADMIN) && (config & PT_BYPASS_MASK) == config)
>> + return true;
>> +
>> + if ((config & PT_CONFIG_MASK) != config)
>> + return false;
>> +
>> + return true;
>> +}
>
> This seems to suggest PT is available to !priv users, is this right?

Yes, that's the intention. PT does CPL-based filtering in hardware and
unlike previous attempts at branch tracing, does not leak out-of-context
addresses (or any other information for that matter).

Regards,
--
Alex


\
 
 \ /
  Last update: 2014-10-24 10:21    [W:1.897 / U:0.016 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site