From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [RFC PATCH] tools/memory-model: Remove (dep ; rfi) from ppo
Date: Tue, 26 Feb 2019 10:30:09 +0100
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To: "Paul E. McKenney" <paulmck@linux.ibm.com>
Cc: Andrea Parri <andrea.parri@amarulasolutions.com>, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, Alan Stern <stern@rowland.harvard.edu>, Will Deacon <will.deacon@arm.com>, Boqun Feng <boqun.feng@gmail.com>, Nicholas Piggin <npiggin@gmail.com>, David Howells <dhowells@redhat.com>, Jade Alglave <j.alglave@ucl.ac.uk>, Luc Maranget <luc.maranget@inria.fr>, Akira Yokosawa <akiyks@gmail.com>, Daniel Lustig <dlustig@nvidia.com>
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On Mon, Feb 25, 2019 at 09:55:17AM -0800, Paul E. McKenney wrote:
> But if you know of any code in the Linux kernel that needs to compare
> pointers, one of which might be in the process of being freed, please
> do point me at it.

I'm having the utmost difficulty of understanding why that would be a
problem. It's just a value. Freeing memory does not affect the actual
memory or any pointers to it.

*confusion*

None of this makes any kind of sense.

From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Tue, 26 Feb 2019 10:30:09 +0100
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [RFC PATCH] tools/memory-model: Remove (dep ; rfi) from ppo
Message-ID: <20190226093009.GS32477@hirez.programming.kicks-ass.net>
References: <1550617057-4911-1-git-send-email-andrea.parri@amarulasolutions.com>
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On Mon, Feb 25, 2019 at 09:55:17AM -0800, Paul E. McKenney wrote:
> But if you know of any code in the Linux kernel that needs to compare
> pointers, one of which might be in the process of being freed, please
> do point me at it.

I'm having the utmost difficulty of understanding why that would be a
problem. It's just a value. Freeing memory does not affect the actual
memory or any pointers to it.

*confusion*

None of this makes any kind of sense.