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Date: Tue, 30 Apr 2024 09:50:11 -0700
From: Kees Cook <keescook@chromium.org>
To: =?iso-8859-1?Q?Micka=EBl_Sala=FCn?= <mic@digikod.net>
Cc: Jakub Kicinski <kuba@kernel.org>, Shuah Khan <shuah@kernel.org>,
	Mark Brown <broonie@kernel.org>,
	Christian Brauner <brauner@kernel.org>,
	Shengyu Li <shengyu.li.evgeny@gmail.com>,
	"David S . Miller" <davem@davemloft.net>,
	=?iso-8859-1?Q?G=FCnther?= Noack <gnoack@google.com>,
	Will Drewry <wad@chromium.org>,
	kernel test robot <oliver.sang@intel.com>,
	linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH v3 0/9] Fix Kselftest's vfork() side effects
Message-ID: <202404300949.28CC6811C0@keescook>
References: <20240429191911.2552580-1-mic@digikod.net>
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On Tue, Apr 30, 2024 at 06:38:40PM +0200, Mickaël Salaün wrote:
> On Tue, Apr 30, 2024 at 08:13:04AM -0700, Jakub Kicinski wrote:
> > On Tue, 30 Apr 2024 15:54:38 +0200 Mickaël Salaün wrote:
> > > Jakub, can you please review it?
> > 
> > I looked thru it. I don't have the cycles to investigate and suggest 
> > a better approach but the sprinkling of mmaps(), if nothing else, feels
> > a bit band-aid-y ????️
> 
> The only mmap that could have side effects on existing tests in the
> _metadata one, but in fact it would reveal issues in tests, so at the
> end I think it's a good thing.
> 
> I'd like "self" to not be conditionally shared but that would require
> changes in several tests.  Let's keep that for another release. :)
> 
> I also noticed that mmap() is already used in test_harness_run() with
> results.

Yeah, I was initially worried about adding this complexity, but at the
end of the day it actually makes things more robust. I'm in favor of it.

-Kees

-- 
Kees Cook