From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm1-f66.google.com ([209.85.128.66]:35174 "EHLO mail-wm1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725858AbeJLE7R (ORCPT ); Fri, 12 Oct 2018 00:59:17 -0400 Date: Fri, 12 Oct 2018 00:30:06 +0300 From: Alexey Dobriyan To: Cyrill Gorcunov Cc: Rafael David Tinoco , linux-kselftest@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, shuah@kernel.org Subject: Re: [PATCH] proc: fix proc-self-map-files selftest for arm Message-ID: <20181011213006.GA13485@avx2> References: <20181011184359.15627-1-rafael.tinoco@linaro.org> <20181011205601.GA32757@avx2> <20181011210256.GE2401@uranus.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20181011210256.GE2401@uranus.lan> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Fri, Oct 12, 2018 at 12:02:56AM +0300, Cyrill Gorcunov wrote: > On Thu, Oct 11, 2018 at 11:56:01PM +0300, Alexey Dobriyan wrote: > > > > As the comment in the beginning says this test is specifically for addresss 0. > > Maybe it should be ifdeffed with __arm__ then. > > Is there some other reason than allocating non-mergable VMA? IIRC the reason is to test address 0 as it is effectively banned for userspace so if it will be broken, it will be broken silently for a long time. As for "unmergeable" libc here doesn't map /dev/zero. I know how to avoid even theoretical breakage by creating binaries by hand but it will be probably too much.