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Date: Sat, 10 Nov 2018 21:49:57 +0300
From: Alexey Dobriyan <adobriyan@gmail.com>
To: Rafael David Tinoco <rafael.tinoco@linaro.org>
Cc: gorcunov@gmail.com, akpm@linux-foundation.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-kselftest@vger.kernel.org, shuah@kernel.org
Subject: Re: [PATCH] proc: fix and merge proc-self-map-file tests
Message-ID: <20181110184957.GB18252@avx2>
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 <20181109113036.21512-1-rafael.tinoco@linaro.org>
 <20181110174727.GA26417@avx2>
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On Sat, Nov 10, 2018 at 03:56:03PM -0200, Rafael David Tinoco wrote:
> On Sat, Nov 10, 2018, at 3:47 PM, Alexey Dobriyan wrote:
> > On Fri, Nov 09, 2018 at 09:30:36AM -0200, Rafael David Tinoco wrote:
> > > Merge proc-self-map-files tests into one since this test should focus in
> > > testing readlink in /proc/self/map_files/* only, and not trying to test
> > > mapping virtual address 0.
> > > 
> > > Lowest virtual address for user space mapping in other architectures,
> > > like arm, is *at least* *(PAGE_SIZE * 2) and NULL hint does not
> > > guarantee that when MAP_FIXED flag, important to this test, is given.
> > > This patch also fixes this issue in remaining test.
> > 
> > > -	p = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE, fd, 0);
> > > +	p = mmap((void *) (2 * PAGE_SIZE), PAGE_SIZE, PROT_NONE,
> > 
> > I don't know ARM. Is this 2 page limitation a limitation of hardware or
> > kernel's?
> 
> Kernel:
> https://bugs.linaro.org/show_bug.cgi?id=3782#c7

Ahh. please test the path I've sent, I don't have arm install readily
available.