From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ED8ADC433EF for ; Wed, 16 Feb 2022 19:12:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238041AbiBPTMc (ORCPT ); Wed, 16 Feb 2022 14:12:32 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:47006 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238040AbiBPTM3 (ORCPT ); Wed, 16 Feb 2022 14:12:29 -0500 Received: from mail-ej1-x629.google.com (mail-ej1-x629.google.com [IPv6:2a00:1450:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A95316A046 for ; Wed, 16 Feb 2022 11:12:15 -0800 (PST) Received: by mail-ej1-x629.google.com with SMTP id a23so1498437eju.3 for ; Wed, 16 Feb 2022 11:12:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=MFZAXh0fPBQNBK2R2nIbUxsfdyleJj0WxyfRkLW2ksM=; b=Uluo3RZ4Jb1a8toBJUYIYiZsZX8M8bZSJueR1LtDSK2/kjqFPZc2c843qGVD0412tE SFliv6hazTgZT8N6TuzuCzJcyQvHI2dObibM/hIL7m+6gPVsOUzZllXCXv/NKfiUW3He mdLeagIMwN9s9JKPFRvkLtupmK75oAPH2rWXU= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=MFZAXh0fPBQNBK2R2nIbUxsfdyleJj0WxyfRkLW2ksM=; b=uoVBRizFxbzTtN6xEt5VdbdcOD6KFDY6kifPkLRu9KflZ67F43HMh0x5E9raagOJw4 RMN3372Lx68IEdvjtcbuKTvbSEoNDc5kxFqnjdQ8/rIZPRtosf1Y3LDxKSD3A+HctHCj cLKuUP0x+njDq8cx7T3vk7d3vKsPpVKMeTs87cUTAkmU9MyiKyDGoKEwDJFVL+yNITvJ 4sZr8Ity+Ld4aqKLzQ48czYGxHV5fS8XBjrCgk/DrJ9ERXgA3uOKklVnaayulHcEBr3A MsJ+51qJlHtJ6Rt67UUZKROosapP9tJvih8/FIxHMugdbmTxijsumIuT20Y8jLjQxjCy incw== X-Gm-Message-State: AOAM530Yo3D2AN8Ox9D2fvIhoZNH1Wu2esyWcQlgtvWJUj3Bu1mA5+es 3ETfpvC7oaLLrR5rWAMsf+68hZUpOJATrF0G5xc= X-Google-Smtp-Source: ABdhPJxq9IzKaZipdbheGQ4Mo4iOx7R9uciFKGtTasJhRH3bVv3g6QV0/e1r5jr+oap56/mee5Jk6A== X-Received: by 2002:a17:906:9947:b0:6cf:e903:fb75 with SMTP id zm7-20020a170906994700b006cfe903fb75mr3362839ejb.400.1645038734067; Wed, 16 Feb 2022 11:12:14 -0800 (PST) Received: from mail-wr1-f41.google.com (mail-wr1-f41.google.com. [209.85.221.41]) by smtp.gmail.com with ESMTPSA id j8sm2342038edw.40.2022.02.16.11.12.13 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 16 Feb 2022 11:12:13 -0800 (PST) Received: by mail-wr1-f41.google.com with SMTP id k1so5063450wrd.8 for ; Wed, 16 Feb 2022 11:12:13 -0800 (PST) X-Received: by 2002:a05:651c:549:b0:243:d87d:4f5a with SMTP id q9-20020a05651c054900b00243d87d4f5amr3232911ljp.443.1645038284648; Wed, 16 Feb 2022 11:04:44 -0800 (PST) MIME-Version: 1.0 References: <20200917112538.GD8409@ziepe.ca> <20200917193824.GL8409@ziepe.ca> <20200918164032.GA5962@xz-x1> <20200918173240.GY8409@ziepe.ca> <20200918204048.GC5962@xz-x1> <0af8c77e-ff60-cada-7d22-c7cfcf859b19@nvidia.com> <20200919000153.GZ8409@ziepe.ca> <20200921083505.GA5862@quack2.suse.cz> <20200921120301.GD8409@ziepe.ca> In-Reply-To: From: Linus Torvalds Date: Wed, 16 Feb 2022 11:04:28 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 1/4] mm: Trial do_wp_page() simplification To: Oded Gabbay , David Hildenbrand Cc: Jason Gunthorpe , Jan Kara , John Hubbard , Leon Romanovsky , Linux-MM , Linux Kernel Mailing List , "Maya B . Gokhale" , Yang Shi , Marty Mcfadden , Kirill Shutemov , Oleg Nesterov , Jann Horn , Kirill Tkhai , Andrea Arcangeli , Christoph Hellwig , Andrew Morton , Daniel Vetter , Greg Kroah-Hartman , Peter Xu Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Added David Hildenbrand to the participants. David, see https://bugzilla.kernel.org/show_bug.cgi?id=215616 for details ] On Wed, Feb 16, 2022 at 8:59 AM Oded Gabbay wrote: > > All the details are in the bug, but the bottom line is that somehow, > this patch causes corruption when the numa balancing feature is > enabled AND we don't use process affinity AND we use GUP to pin pages > so our accelerator can DMA to/from system memory. Hmm. I thought all the remaining issues were related to THP - and David Hildenbrand had a series to fix those up. The fact that it also shows up with numa balancing is a bit unfortunate, because I think that means that that patch series may not have caught that case. That said - what does "we use GUP to pin pages" mean? Does it actually use the pinning logic, or just regular old GUP? I'm assuming this is just the existing pin_user_pages_fast() (ie a proper pin) in drivers/misc/habanalabs/common/memory.c. But I wanted to confirm that it's not some other situation. Linus