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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5D0DFC433F5 for ; Tue, 19 Oct 2021 06:23:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 37C76610A1 for ; Tue, 19 Oct 2021 06:23:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234178AbhJSG0I (ORCPT ); Tue, 19 Oct 2021 02:26:08 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:50458 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234165AbhJSG0H (ORCPT ); Tue, 19 Oct 2021 02:26:07 -0400 Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id 346CE2197E; Tue, 19 Oct 2021 06:23:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1634624633; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=aNvJPt85vZf9bBMJjbgwMuKxAMmcbsHIJPwZz/3xngo=; b=aPPUZQip1FXzonJxM4wqd/690HrZk6fz9rhHm/1JCFBw9ALlZDpceFtf6flMY3j6oMRMFe AQmevTkq51HUk5WPl3N4P1eN9xv890mbZxJ7GfHV8xreOSPvAbt4ZkskV7eS7JuJeAvANa 9uoyyw60aVq6hbOMcli3eofF+oZayMg= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1634624633; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=aNvJPt85vZf9bBMJjbgwMuKxAMmcbsHIJPwZz/3xngo=; b=GijXbiZXw/n+u9uG38fm5BwLSEeX5PBkSlrFwGvVSFdmfffvdMVEtRW9XLwkcJp1P8EfmE 6ukLpP3n3DF7j3Dw== Received: from pobox.suse.cz (pobox.suse.cz [10.100.2.14]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id 0341FA3B8A; Tue, 19 Oct 2021 06:23:52 +0000 (UTC) Date: Tue, 19 Oct 2021 08:23:51 +0200 (CEST) From: Miroslav Benes To: Ming Lei cc: Luis Chamberlain , Benjamin Herrenschmidt , Paul Mackerras , tj@kernel.org, gregkh@linuxfoundation.org, akpm@linux-foundation.org, minchan@kernel.org, jeyu@kernel.org, shuah@kernel.org, bvanassche@acm.org, dan.j.williams@intel.com, joe@perches.com, tglx@linutronix.de, keescook@chromium.org, rostedt@goodmis.org, linux-spdx@vger.kernel.org, linux-doc@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v8 11/12] zram: fix crashes with cpu hotplug multistate In-Reply-To: Message-ID: References: <20210927163805.808907-12-mcgrof@kernel.org> User-Agent: Alpine 2.21 (LSU 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org > > By you only addressing the deadlock as a requirement on approach a) you are > > forgetting that there *may* already be present drivers which *do* implement > > such patterns in the kernel. I worked on addressing the deadlock because > > I was informed livepatching *did* have that issue as well and so very > > likely a generic solution to the deadlock could be beneficial to other > > random drivers. > > In-tree zram doesn't have such deadlock, if livepatching has such AA deadlock, > just fixed it, and seems it has been fixed by 3ec24776bfd0. I would not call it a fix. It is a kind of ugly workaround because the generic infrastructure lacked (lacks) the proper support in my opinion. Luis is trying to fix that. Just my two cents. Miroslav