From mboxrd@z Thu Jan  1 00:00:00 1970
Return-path: <dave.hansen@linux.intel.com>
Received: from mga02.intel.com ([134.134.136.20])
	by Galois.linutronix.de with esmtps (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256)
	(Exim 4.80)
	(envelope-from <dave.hansen@linux.intel.com>)
	id 1fJjxf-0006hK-3O
	for speck@linutronix.de; Fri, 18 May 2018 20:18:40 +0200
Subject: [MODERATED] Re: Generic eBPF hardening
References: <edeaf2b7-3219-9d21-4c73-b1545a197303@intel.com>
 <20180517222233.xk3favfebt4wiiid@ast-mbp>
 <20180517225448.GC4486@tassilo.jf.intel.com>
 <20180517232115.mwmns6w6t32mjeze@ast-mbp>
From: Dave Hansen <dave.hansen@linux.intel.com>
Message-ID: <31409ed3-62aa-cb1d-2145-203a686d98a7@linux.intel.com>
Date: Fri, 18 May 2018 11:18:26 -0700
MIME-Version: 1.0
In-Reply-To: <20180517232115.mwmns6w6t32mjeze@ast-mbp>
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 7bit
To: speck@linutronix.de
List-ID: <speck.linutronix.de>

On 05/17/2018 04:21 PM, speck for Alexei Starovoitov wrote:
> The main use case for unprivileged bpf is so_reuseport and socket filters.
> It's critical path of networking receive side.
> Adding lfence after every program won't be cheap.

Alexei, do you have any "benchmarks" or tests for these paths that you
regularly run to look for performance regressions?  I'd definitely want
to run those as we look at potential mitigations.