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=-3.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,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 2A199C46475 for ; Tue, 23 Oct 2018 15:49:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D3BE220652 for ; Tue, 23 Oct 2018 15:49:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="k0adIbb8" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D3BE220652 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 S1728379AbeJXANI (ORCPT ); Tue, 23 Oct 2018 20:13:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:40854 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727437AbeJXANI (ORCPT ); Tue, 23 Oct 2018 20:13:08 -0400 Received: from localhost (unknown [185.7.230.214]) (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 EB8A020652; Tue, 23 Oct 2018 15:49:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1540309751; bh=OtDAkJ5WP5ygueOGQcHF2S6JPxgCh/geZXn/huDDOVk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=k0adIbb8qN6UsU/oPP1t0YjhPnxszCAX2ulMjRBErCW5XNP0Wsf6kMJJgYvy1VHFc nJTlMeDG+HioqUWjKLBvq/IB7CMYCpRgOl3JGbLP0wBnVpw5cPxsZBq8ZxIIJbmcbm 7KIkDOe1sVBqAnM8OnsqUkWYj4gYFDyVWsiN0beE= Date: Tue, 23 Oct 2018 11:49:08 -0400 From: Sasha Levin To: Dmitry Torokhov Cc: stable@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH AUTOSEL 4.18 08/27] Input: evdev - add a schedule point in evdev_write() Message-ID: <20181023154908.GB24189@sasha-vm> References: <20181022101924.40531-1-sashal@kernel.org> <20181022101924.40531-8-sashal@kernel.org> <20181022170244.GB27929@dtor-ws> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20181022170244.GB27929@dtor-ws> 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 Mon, Oct 22, 2018 at 10:02:44AM -0700, Dmitry Torokhov wrote: >Hi Sasha, > >On Mon, Oct 22, 2018 at 06:19:05AM -0400, Sasha Levin wrote: >> From: Dmitry Torokhov >> >> [ Upstream commit 36d2582ff235b4e01ad64a734c877a52dc762d9c ] >> >> Large writes to evdev interface may cause rcu stalls. Let's add >> cond_resched() to the loop to avoid this. > >This is not needed in stable: > >- the interfaces are not accessible for unprivileged users so there is > no DOS concerns >- the issue can only happen on non-preemptible kernels >- the issue only showed up with synthetic test and not real life use > cases >- this is not a regression > >The same goes to similar patches to mousedev, joydev and uinput that you >autoselected. Dropped, thanks! -- Thanks, Sasha