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=-4.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 AE6B8C433C1 for ; Fri, 19 Mar 2021 15:06:39 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 34DD46191A for ; Fri, 19 Mar 2021 15:06:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 34DD46191A 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-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=hYpq+n7jmVai7xMmTZbJRfw0InIjD0e8UwT7k73w1nI=; b=foQwQJVj6JawojovdWm0sVLRF 3EZGLQ0z/TUE5MvTAs+xl3wk4V3I3aDHjdhzEXIldfV9ePCNlVQCbHG+nTtbIMVRZCToXMgo835sh 9tRdYV/tmH1QZeEy9MammYCZ1+WHBBTHmVBLMy2E99E6WtO63l6lBmeVHoF2E/FPXA2pnKSDQakVa 9We4zusUokvje7+l6KXvSu+aWl0vWTE08YMyCTHIFBx1yRJZyaUvfgo1Yjn04tUtZV/Xi3uNwYbEJ lMwB1qHueqFSywSFlZKcvPdcLHoT1k7SsmehvKNU5RUR/VOG4ExqhaHTe1S+5OJ0T5PFsGmmcm1LH K4FCkrRRQ==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lNGgd-007am3-LB; Fri, 19 Mar 2021 15:05:15 +0000 Received: from mail.kernel.org ([198.145.29.99]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lNGgX-007al9-GH for linux-arm-kernel@lists.infradead.org; Fri, 19 Mar 2021 15:05:12 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id C5FCF6191A; Fri, 19 Mar 2021 15:05:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1616166307; bh=Jpyg1aRj2xrunboT1i35yraE5HMpPPlzSno+6EE70Z0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=dqdONhO25lJw7lATZ7aW9sLvHqX7cjABakXKej3SxsUYqxOlUnC+xW/oFbCI98da5 bbYvkLwykwSb188+8+wkvUuNXkSuMKdtSO0DT0lO8FsQV5iCqNIMeH8HT/xv1J/iWD 6f4vOw87EwjhwdQBYDt1AmU3grJUcy8kWJANkUJ6qYsIEBb2rSxrtODn2le1pOBe7/ yRUIq5VikeKrn5DkZKDf16vnTeTwOIErz7me/lK9UXm8SAHUz6wPozoo8udQcfFh36 2EyMktDT3CobPoajsknVOG9EypTc7HyUyl/BOYST6FcnhO2lhSt6ufO1IaXb44SYR4 resbEsRbRk4gw== Received: from johan by xi.lan with local (Exim 4.93.0.4) (envelope-from ) id 1lNGgq-0005df-Fi; Fri, 19 Mar 2021 16:05:28 +0100 Date: Fri, 19 Mar 2021 16:05:28 +0100 From: Johan Hovold To: Andy Shevchenko Cc: =?utf-8?B?RGXDoWss?= Imre , "Song Bao Hua (Barry Song)" , Finn Thain , Krzysztof Kozlowski , Greg Kroah-Hartman , Jiri Slaby , linux-arm Mailing List , Linux Samsung SOC , "open list:SERIAL DRIVERS" , Linux Kernel Mailing List , Hector Martin , Arnd Bergmann Subject: Re: [PATCH] tty: serial: samsung_tty: remove spinlock flags in interrupt handlers Message-ID: References: <20210315181212.113217-1-krzysztof.kozlowski@canonical.com> <4771468d968a44789518bc547acf5f93@hisilicon.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210319_150509_744948_449AD219 X-CRM114-Status: GOOD ( 13.22 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Mar 19, 2021 at 12:09:34PM +0200, Andy Shevchenko wrote: > On Fri, Mar 19, 2021 at 10:09 AM Johan Hovold wrote: > > > I think it is almost always wrong to call spin_lock_irqsave in > > > hardirq. > > > > Again, no. It's even been a requirement due to "threadirqs" in some > > cases (e.g. hrtimers) up until now (or rather until the above patch is > > in mainline). > > By the way, a good question Imre (Cc'ed) and I have discussed is the > in-kernel documentation, i.e. > https://www.kernel.org/doc/html/latest/kernel-hacking/locking.html. > Should it be adjusted to reality? Once forced threading disables interrupts (as it should have all along) we don't need to worry about this anymore. But yeah, otherwise it should be documented. Johan _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel