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Date:   Fri, 15 Jun 2018 09:45:04 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Jin Yao <yao.jin@linux.intel.com>
Cc:     acme@kernel.org, jolsa@kernel.org, mingo@redhat.com,
        alexander.shishkin@linux.intel.com, me@kylehuey.com,
        Linux-kernel@vger.kernel.org, vincent.weaver@maine.edu,
        will.deacon@arm.com, eranian@google.com, namhyung@kernel.org,
        ak@linux.intel.com, kan.liang@intel.com, yao.jin@intel.com
Subject: Re: [PATCH v1 0/2] perf: Drop leaked kernel samples
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On Fri, Jun 15, 2018 at 06:03:21PM +0800, Jin Yao wrote:
> On workloads that do a lot of kernel entry/exits we see kernel
> samples, even though :u is specified. This is due to skid existing.
> 
> This might be a security issue because it can leak kernel addresses even
> though kernel sampling support is disabled.
> 
> One patch "perf/core: Drop kernel samples even though :u is specified"
> was posted in last year but it was reverted because it introduced a
> regression issue that broke the rr-project.
> 
> Now this patch set uses sysctl to control the dropping of leaked
> kernel samples.

So what happened to the suggestion of keeping the samples but 0-stuffing
all the tricky bits?