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=-5.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,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 54268C433DF for ; Wed, 26 Aug 2020 21:46:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 03F002087C for ; Wed, 26 Aug 2020 21:46:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598478387; bh=82XFB/7i5TWDnH2NxU3bR3A631fDgBFkAC19Mgw+OY8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=s9FgB5wiq8AMCBfp2lltVe7krdbRHUQr9imaqiP9Xzi5jtYo4MvxxZzC86iSmKN6A Gtnz6LEwglJbqcAPRRwQCYdwUinQ5POEzc1LvjHGjd80WeLtdmILPSDcOKBs3dAd5x K/dVItRsGlWd7NJhcrKpbV9Gpu/VGrA4rC2V8L/I= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726770AbgHZVq0 (ORCPT ); Wed, 26 Aug 2020 17:46:26 -0400 Received: from mail.kernel.org ([198.145.29.99]:57798 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726753AbgHZVq0 (ORCPT ); Wed, 26 Aug 2020 17:46:26 -0400 Received: from localhost (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (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 D9E07207CD; Wed, 26 Aug 2020 21:46:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598478385; bh=82XFB/7i5TWDnH2NxU3bR3A631fDgBFkAC19Mgw+OY8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=vqXJv4v1YCOLauAMozdqLGzCgS3oF04KpHz9NsIYaaM25ZXF64qsdozlmhltkEl2H lw5W8BCURLWLfebqIopHt8cMEaqlf3g+qUJgQpILZ8tbZDBUND5vwWcoG6WrKGtM0H dlA7RIfwaDvZrcH10l6jwM6WI9cx5FDFASrbDNxs= Date: Wed, 26 Aug 2020 17:46:23 -0400 From: Sasha Levin To: Hugh Dickins Cc: Greg KH , aarcange@redhat.com, akpm@linux-foundation.org, kirill.shutemov@linux.intel.com, mike.kravetz@oracle.com, songliubraving@fb.com, torvalds@linux-foundation.org, stable-commits@vger.kernel.org, stable@vger.kernel.org Subject: Re: Patch "khugepaged: khugepaged_test_exit() check mmget_still_valid()" has been added to the 5.8-stable tree Message-ID: <20200826214623.GM8670@sasha-vm> References: <1597841669128213@kroah.com> <20200819135306.GA3311904@kroah.com> <20200822212053.GE8670@sasha-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Wed, Aug 26, 2020 at 11:53:24AM -0700, Hugh Dickins wrote: >On Mon, 24 Aug 2020, Hugh Dickins wrote: >> On Sat, 22 Aug 2020, Hugh Dickins wrote: >> > On Sat, 22 Aug 2020, Sasha Levin wrote: >> > > >> > > I've followed your instructions and backported the patches: >> > > >> > > bbe98f9cadff ("khugepaged: khugepaged_test_exit() check >> > > mmget_still_valid()") - to all branches. >> > > f3f99d63a815 ("khugepaged: adjust VM_BUG_ON_MM() in >> > > __khugepaged_enter()") - to all branches. >> > > 59ea6d06cfa9 ("coredump: fix race condition between collapse_huge_page() >> > > and core dumping") - for 4.4. >> > >> > That's saved me time, thanks a lot for doing that work, Sasha. >> > >> > I've checked the results (haha, read on) and they're all fine, >> > but one minor flaw in bisectability: the added 4.4 backport of >> > "coredump: fix race condition..." adds a line (deleted by the next commit) >> > result = SCAN_ANY_PROCESS; >> > but neither "result" nor "SCAN_ANY_PROCESS" is defined in that tree, >> > so that intermediate step would generate an easily fixed build error. >> > >> > FWIW - I don't know whether that's something to care about or not. >> >> Ah, but I missed that this one that we originally held back from 5.8, >> did not in fact get re-added to 5.8: all the backport series have it, >> but today's 5.8.4-rc1 does not have it. >> >> That's not a disaster - the series builds without it, and having its >> fix without the fixed commit is just odd, no more unsafe than before; >> but it should be re-added for a 5.8.4-rc2 or 5.8.5. > >I see 5.8 is at 5.8.5-rc1 today, but the commit below still missing: >please re-add it, then we can all forget about it at last - thanks! Greg went for a fast release cycle and I didn't have time to queue it up, sorry. But don't worry - this patch isn't forgotten, I'll queue it for the next release on Friday/Saturday. -- Thanks, Sasha