From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: 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 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> Sender: stable-owner@vger.kernel.org List-ID: 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