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 X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7A52FC433DF for ; Fri, 21 Aug 2020 20:35:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A1E6207DF for ; Fri, 21 Aug 2020 20:35:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598042152; bh=iPJvCED2WCBB6L3Yu9e5XQUakMAYNcGoa6MXkWUrumA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=YX8tDWR7qIPl4D2H5/GFiJ5S4puMnqHrZtaWFdARcvWENfPgrmrLVEW+wq1HcLuN5 ayFjaPGp60uiLUFmLEAwghL6jHqdeJAktNmEUNTfHlu88qOkwW64VcnASTBPI/5JBN MI23WUx8skIrNQpcs6HUvd63Zuhw/ZZDcwDJehqk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726766AbgHUUfv (ORCPT ); Fri, 21 Aug 2020 16:35:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:43982 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725938AbgHUUft (ORCPT ); Fri, 21 Aug 2020 16:35:49 -0400 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1298420724; Fri, 21 Aug 2020 20:35:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598042149; bh=iPJvCED2WCBB6L3Yu9e5XQUakMAYNcGoa6MXkWUrumA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=dbaA4CUK3S7ylOEHuTbLGNOwHFvx8fACqtTK81nq1Pfs6mklJI2pVOyllUZIBwgkA 2gP2mGv6TFJUrJrpJs3Y5YUwJe4jzcPSu8xJJ7m7w/1L+3XPF6jJI66onZTm3lhCCT 10TD6KyGhdLdFgTyXgMiVJZigkVH74U4HKn1XHl4= Date: Fri, 21 Aug 2020 13:35:48 -0700 From: Andrew Morton To: Joerg Roedel Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Chris Wilson , intel-gfx@lists.freedesktop.org, Pavel Machek , Linus Torvalds , Dave Airlie , Joonas Lahtinen , Rodrigo Vivi , David Vrabel , Joerg Roedel , stable@vger.kernel.org Subject: Re: [PATCH v2] mm: Track page table modifications in __apply_to_page_range() Message-Id: <20200821133548.be58a3b0881b41a32759fa04@linux-foundation.org> In-Reply-To: <20200821123746.16904-1-joro@8bytes.org> References: <20200821123746.16904-1-joro@8bytes.org> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 21 Aug 2020 14:37:46 +0200 Joerg Roedel wrote: > The __apply_to_page_range() function is also used to change and/or > allocate page-table pages in the vmalloc area of the address space. > Make sure these changes get synchronized to other page-tables in the > system by calling arch_sync_kernel_mappings() when necessary. There's no description here of the user-visible effects of the bug. Please always provide this, especially when proposing a -stable backport. Take pity upon all the downstream kernel maintainers who are staring at this wondering whether they should risk adding it to their kernels.