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[142.162.115.133]) by smtp.gmail.com with ESMTPSA id t71sm6437470qka.86.2021.02.26.06.42.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 26 Feb 2021 06:42:01 -0800 (PST) Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1lFeJc-000tBv-SJ; Fri, 26 Feb 2021 10:42:00 -0400 Date: Fri, 26 Feb 2021 10:42:00 -0400 From: Jason Gunthorpe To: Matthew Wilcox Cc: linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: Freeing page tables through RCU Message-ID: <20210226144200.GV2643399@ziepe.ca> References: <20210225205820.GC2858050@casper.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210225205820.GC2858050@casper.infradead.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 25, 2021 at 08:58:20PM +0000, Matthew Wilcox wrote: > I'd like to hear better ideas than this. You didn't like my suggestion to put a sleepable lock around the freeing of page tables during flushing? I still don't see how you convert the sleepable page walkers to use rcu?? Jason