From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 34D14211C; Tue, 19 Nov 2024 11:58:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732017526; cv=none; b=nMRDR0HywiyLxc+M63WhiN+cCrrRBUdgEu0LUFmZp9GQcT6784vR0a1GWbA1OIqK6pu60YKNQt9pB83ZHroJZAvUPsuUc/oVndKkK6QwwHlajBzn0HdOIWIE0zYVgANP6EE+/eavWrw9Miy6BW/L/MR6iJUL6bnxE9BEAU6rQwQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732017526; c=relaxed/simple; bh=K8FMiqW5NIEUmvDDVxv170oLszWNxCd/M4x52+9ZjMU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ls3WdjXo2zFPwgzlpXw0rhjakCddID2maxCFo2Rn/9s14fbg+KPyZlXcZ4Kur6/wStmOv9jUjk4dJQUeOH6jDfSH29ClrownJ95gRapoUTXggZWZ34u+rY9Imqhls+yMOXFxBW+8HHmw+85HnH9Bs7s7t1iBZ+gmOSAk/ypcRtU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=WmOupbsO; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="WmOupbsO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C3BCC4CECF; Tue, 19 Nov 2024 11:58:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1732017525; bh=K8FMiqW5NIEUmvDDVxv170oLszWNxCd/M4x52+9ZjMU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=WmOupbsOU5umXwVorZ1Imowtg2Nkw2bvxxvg4PPd02ZggC3EKr2DnqgT/uzl6J5Cf l0uGiItxip2UQ6YLt62knmbBLKqcnbONHHu2LiKExlUx/T7tzIVMFNQ86nEQozod5g fSGeH5YEjbOgdEvznYNXWvQR6RtIrSSe0rlBrA+Y= Date: Tue, 19 Nov 2024 12:58:21 +0100 From: Greg KH To: Omar Sandoval Cc: stable@vger.kernel.org, Jiri Olsa , Andrii Nakryiko , bpf@vger.kernel.org, Daniel Borkmann , Andrii Nakryiko Subject: Re: Fix build ID parsing logic in stable trees Message-ID: <2024111955-excursion-diaper-2675@gregkh> References: <2024110536-agonizing-campus-21f0@gregkh> <2024110636-rebound-chip-f389@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Fri, Nov 15, 2024 at 10:19:25AM -0800, Omar Sandoval wrote: > On Wed, Nov 13, 2024 at 10:12:39PM +0100, Jiri Olsa wrote: > > On Wed, Nov 13, 2024 at 12:07:39PM -0800, Andrii Nakryiko wrote: > > > On Fri, Nov 8, 2024 at 3:26 PM Jiri Olsa wrote: > > > > > > > > On Fri, Nov 08, 2024 at 09:35:34AM +0100, Jiri Olsa wrote: > > > > > On Thu, Nov 07, 2024 at 12:04:05PM -0800, Omar Sandoval wrote: > > > > > > On Wed, Nov 06, 2024 at 12:57:34PM +0100, Jiri Olsa wrote: > > > > > > > On Wed, Nov 06, 2024 at 07:12:05AM +0100, Greg KH wrote: > > > > > > > > On Tue, Nov 05, 2024 at 10:15:04AM +0100, Jiri Olsa wrote: > > > > > > > > > On Tue, Nov 05, 2024 at 07:54:48AM +0100, Greg KH wrote: > > > > > > > > > > On Mon, Nov 04, 2024 at 06:52:52PM +0100, Jiri Olsa wrote: > > > > > > > > > > > hi, > > > > > > > > > > > sending fix for buildid parsing that affects only stable trees > > > > > > > > > > > after merging upstream fix [1]. > > > > > > > > > > > > > > > > > > > > > > Upstream then factored out the whole buildid parsing code, so it > > > > > > > > > > > does not have the problem. > > > > > > > > > > > > > > > > > > > > Why not just take those patches instead? > > > > > > > > > > > > > > > > > > I guess we could, but I thought it's too big for stable > > > > > > > > > > > > > > > > > > we'd need following 2 changes to fix the issue: > > > > > > > > > de3ec364c3c3 lib/buildid: add single folio-based file reader abstraction > > > > > > > > > 60c845b4896b lib/buildid: take into account e_phoff when fetching program headers > > > > > > > > > > > > > > > > > > and there's also few other follow ups: > > > > > > > > > 5ac9b4e935df lib/buildid: Handle memfd_secret() files in build_id_parse() > > > > > > > > > cdbb44f9a74f lib/buildid: don't limit .note.gnu.build-id to the first page in ELF > > > > > > > > > ad41251c290d lib/buildid: implement sleepable build_id_parse() API > > > > > > > > > 45b8fc309654 lib/buildid: rename build_id_parse() into build_id_parse_nofault() > > > > > > > > > 4e9d360c4cdf lib/buildid: remove single-page limit for PHDR search > > > > > > > > > > > > > > > > > > which I guess are not strictly needed > > > > > > > > > > > > > > > > Can you verify what exact ones are needed here? We'll be glad to take > > > > > > > > them if you can verify that they work properly. > > > > > > > > > > > > > > ok, will check > > > > > > > > > > > > Hello, > > > > > > > > > > > > I noticed that the BUILD-ID field in vmcoreinfo is broken on > > > > > > stable/longterm kernels and found this thread. Can we please get this > > > > > > fixed soon? > > > > > > > > > > > > I tried cherry-picking the patches mentioned above ("lib/buildid: add > > > > > > single folio-based file reader abstraction" and "lib/buildid: take into > > > > > > account e_phoff when fetching program headers"), but they don't apply > > > > > > cleanly before 6.11, and they'd need to be reworked for 5.15, which was > > > > > > before folios were introduced. Jiri's minimal fix works for me and seems > > > > > > like a much safer option. > > > > > > > > > > hi, > > > > > thanks for testing > > > > > > > > > > I think for 6.11 we could go with backport of: > > > > > de3ec364c3c3 lib/buildid: add single folio-based file reader abstraction > > > > > 60c845b4896b lib/buildid: take into account e_phoff when fetching program headers > > > > > > > > > > and with the small fix for the rest > > > > > > > > > > but I still need to figure out why also 60c845b4896b is needed > > > > > to fix the issue on 6.11.. hopefully today > > > > > > > > ok, so the fix the issue in 6.11 with upstream backports we'd need both: > > > > > > > > 1) de3ec364c3c3 lib/buildid: add single folio-based file reader abstraction > > > > 2) 60c845b4896b lib/buildid: take into account e_phoff when fetching program headers > > > > > > > > 2) is needed because 1) seems to omit ehdr->e_phoff addition (patch below) > > > > which is added back in 2) > > > > > > > > IMO 6.11 is close to upstream and by taking above upstream fixes it will be > > > > easier to backport other possible fixes in the future, for other trees I'd > > > > take the original one line fix I posted > > > > > > I still maintain that very minimal is the way to go instead of risking > > > bringing new potential regressions by partially backporting folio > > > rework patchset. > > > > > > Jiri, there is no point in risking this, best to fix this quickly and > > > minimally. If we ever need to backport further fixes, *then* we can > > > think about folio-based implementation backport. > > > > ok, make sense, the original plan works for me as well > > > > jirka > > Greg, could you please queue up Jiri's one line fixes for 5.15, 6.1, > 6.6, and 6.11? Ok, will do, but hopefully you all will help out if there's any problems with the change going forward... greg k-h