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Date: Sat, 5 Oct 2024 18:15:37 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-kernel@vger.kernel.org, Nicholas Piggin <npiggin@gmail.com>,
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	Jonas Oberhauser <jonas.oberhauser@huaweicloud.com>,
	rcu@vger.kernel.org, linux-mm@kvack.org, lkmm@lists.linux.dev
Subject: Re: [RFC PATCH 0/4] sched+mm: Track lazy active mm existence with
 hazard pointers
Message-ID: <20241005161537.GB18071@noisy.programming.kicks-ass.net>
References: <20241002010205.1341915-1-mathieu.desnoyers@efficios.com>
 <CAHk-=wgztWbA4z85xKob4eS9P=Nt5h4j=HnN+Pc90expskiCRA@mail.gmail.com>
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On Wed, Oct 02, 2024 at 10:39:15AM -0700, Linus Torvalds wrote:
> So I think the real issue is that "active_mm" is an old hack from a
> bygone era when we didn't have the (much more involved) full TLB
> tracking.

I still seem to have these patches that neither Andy nor I ever managed
to find time to finish:

  https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git/log/?h=x86/lazy