From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 B6DA22CCDB; Tue, 1 Apr 2025 14:14:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743516856; cv=none; b=C7ZdQg62pK3CwPzcUcSsK6LEYvsWt1CVLaUYenXJw72O5MVKR23r5g8kj5oqAeunnjYKi4XeF/Y1k7dbZLTYooknRFcu1Sf1fe9Ada2s/o0pjBvki/l6AJRY/o08/g/8VY4vxU9p2t7lqYU661VeV4/gEb8t3XzmpCTgWrZbu6I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743516856; c=relaxed/simple; bh=pfww1HNIhX2W5e2p8Rt3s+mhdpaIwMwHArsMA4l2kzw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=d2Y0ggYytecIvHvQ6vlYK+esA7mzxmOuR1f9KXlmpl+RlhW14GXt3TqIiFkREI4rA2t/ykj3y65F/GU2toMnsxXj6bC26cWwCEO34aur/o2XK/H+5cE5wb+r9tEpRq7rzSSjHl+LybpDhdm9Zx+crmjMbEsmu8zCUmwlM26pRuk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=lab9yKVN; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="lab9yKVN" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=Z+1jhJsrt5pd24RiVBmd8llv61EuQXGt++6EKuQpt3Q=; b=lab9yKVNjzRTmzv2vqjTz/W4ou RSJoGookb++Txka+rMabWIU+DDuzyfSFkuhB9UeBF/drIStf0TD5eq0I9itGgqObtA52b1qnDecIb dVgerrkukiUuIcySdypgvCWkm3cHuJuSLRtZo2mABPrZxs0KpzDNER7LwRLlMuLvy0CmfUsU09xwA 6U32skHrc0hCQdZroHC6nEY5+jwXHiGr+BV/dYT8qOwRdW/I+K/MDR1HUeqb4zUkGRv6rn/YM7H7d +RchJ7Jz0EcnzacUiOmta/Ub8QJytGTCdio1oQ9T4pyW2+b47cbxasA3Mqhf+PAvlqQeVSGbNE446 AtIT8AFA==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.1 #2 (Red Hat Linux)) id 1tzcNT-00000006pSO-373V; Tue, 01 Apr 2025 14:14:08 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 31E9730049D; Tue, 1 Apr 2025 16:14:07 +0200 (CEST) Date: Tue, 1 Apr 2025 16:14:07 +0200 From: Peter Zijlstra To: Christian Brauner Cc: linux-fsdevel@vger.kernel.org, jack@suse.cz, rafael@kernel.org, Ard Biesheuvel , linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, James Bottomley , mcgrof@kernel.org, hch@infradead.org, david@fromorbit.com, djwong@kernel.org, pavel@kernel.org, mingo@redhat.com, will@kernel.org, boqun.feng@gmail.com Subject: Re: [PATCH 0/6] power: wire-up filesystem freeze/thaw with suspend/resume Message-ID: <20250401141407.GE5880@noisy.programming.kicks-ass.net> References: <20250331-work-freeze-v1-0-6dfbe8253b9f@kernel.org> <20250401-work-freeze-v1-0-d000611d4ab0@kernel.org> Precedence: bulk X-Mailing-List: linux-efi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250401-work-freeze-v1-0-d000611d4ab0@kernel.org> On Tue, Apr 01, 2025 at 02:32:45AM +0200, Christian Brauner wrote: > The whole shebang can also be found at: > https://web.git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git/log/?h=work.freeze > > I know nothing about power or hibernation. I've tested it as best as I > could. Works for me (TM). > > I need to catch some actual sleep now... > > --- > > Now all the pieces are in place to actually allow the power subsystem to > freeze/thaw filesystems during suspend/resume. Filesystems are only > frozen and thawed if the power subsystem does actually own the freeze. Urgh, I was relying on all kthreads to be freezable for live-patching: https://lkml.kernel.org/r/20250324134909.GA14718@noisy.programming.kicks-ass.net So I understand the problem with freezing filesystems, but can't we leave the TASK_FREEZABLE in the kthreads? The way I understand it, the power subsystem will first freeze the filesystems before it goes freeze threads anyway. So them remaining freezable should not affect anything, right?