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=-6.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham 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 B33ADC46475 for ; Thu, 25 Oct 2018 20:07:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6F2092083E for ; Thu, 25 Oct 2018 20:07:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="M3173EfA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6F2092083E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727579AbeJZEmD (ORCPT ); Fri, 26 Oct 2018 00:42:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:56950 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725905AbeJZEmC (ORCPT ); Fri, 26 Oct 2018 00:42:02 -0400 Received: from localhost (unknown [167.98.65.38]) (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 CCCCB20834; Thu, 25 Oct 2018 20:07:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1540498073; bh=eyIobkJUoHAa2IUccYhd0jPz+nDkz8l1cih0JD7q38E=; h=Date:From:To:Subject:References:In-Reply-To:From; b=M3173EfA8uh0SzcTEy+Rl1X45xrv6iFgSk8ztUFXoi7A/ScFyXSyI1V3z940sVjgs AYCgyq59wSzEcm6AJJpHVJJo7BTIztsOVLyU0p0WVV1T613CIy8X5jmIZVmpSse/RP L2Zp/H0rC7PT5T1Q1ZvVP2KBv6ym/iLwH/J9P0GU= Date: Thu, 25 Oct 2018 16:07:51 -0400 From: Sasha Levin To: dsterba@suse.cz, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Jiri Kosina Subject: Re: [PATCH AUTOSEL 4.4 08/65] btrfs: cleaner_kthread() doesn't need explicit freeze Message-ID: <20181025200751.GB1693@sasha-vm> References: <20181025141705.213937-1-sashal@kernel.org> <20181025141705.213937-8-sashal@kernel.org> <20181025150729.GD16290@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20181025150729.GD16290@suse.cz> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 25, 2018 at 05:07:29PM +0200, David Sterba wrote: >On Thu, Oct 25, 2018 at 10:16:08AM -0400, Sasha Levin wrote: >> From: Jiri Kosina >> >> [ Upstream commit 838fe1887765f4cc679febea60d87d2a06bd300e ] >> >> cleaner_kthread() is not marked freezable, and therefore calling >> try_to_freeze() in its context is a pointless no-op. >> >> In addition to that, as has been clearly demonstrated by 80ad623edd2d >> ("Revert "btrfs: clear PF_NOFREEZE in cleaner_kthread()"), it's perfectly >> valid / legal for cleaner_kthread() to stay scheduled out in an arbitrary >> place during suspend (in that particular example that was waiting for >> reading of extent pages), so there is no need to leave any traces of >> freezer in this kthread. >> >> Fixes: 80ad623edd2d ("Revert "btrfs: clear PF_NOFREEZE in cleaner_kthread()") >> Fixes: 696249132158 ("btrfs: clear PF_NOFREEZE in cleaner_kthread()") >> Signed-off-by: Jiri Kosina >> Signed-off-by: David Sterba >> Signed-off-by: Sasha Levin > >IIRC it was some preparatory work for livepatching. I did a quick check >if this is safe for 4.4 and would say yes, but the patch does not fix >anything so IMO this does not need to go to stable. Doesn't that also affect hibernation and such? -- Thanks, Sasha