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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 ECED9C3A59E for ; Fri, 16 Aug 2019 07:12:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B989B2173E for ; Fri, 16 Aug 2019 07:12:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565939557; bh=hm54zHKSCIASDf9hCE6eR27gl//Kfc0OjNQywYmSlpc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=aeP4L7QpsFbz2MKXbIO7L2EL6MwIzbrNoKe07rsvb7OlqJ1n6prW31rMz0Ue1wcnc W67Gsl4ha9ZuB6j5gx1SIkgyr82sOq1quKd01IsHmf+U1BoEkQ3Taishf3plzUdzOf 7GDR0682HHQJjA2LckBn+eR+X4DgVw8lVRiH23wc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727123AbfHPHMh (ORCPT ); Fri, 16 Aug 2019 03:12:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:37188 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726425AbfHPHMg (ORCPT ); Fri, 16 Aug 2019 03:12:36 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 DACC52133F; Fri, 16 Aug 2019 07:12:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565939556; bh=hm54zHKSCIASDf9hCE6eR27gl//Kfc0OjNQywYmSlpc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=2lRvFbonDZVYz4dPOieZMjgflWbc0txk/HSOXP81HhMZTsHxdV3cJvEJQ/4zRjvdC v+jjzhjRzdCXoQk9JYwiW4uA14q5zVP23O2Mo7S5MfeYGoi0icmPGrfK3sN/R2ZxSU nEj+2x1j1MHrjm1uRdcWmQA7s4hlRSAI3o7PdeIk= Date: Fri, 16 Aug 2019 09:12:34 +0200 From: Greg KH To: Ming Lei Cc: "Ray, Mark C (Global Solutions Engineering (GSE))" , Jens Axboe , "linux-block@vger.kernel.org" , "stable@vger.kernel.org" Subject: Re: [PATCH] blk-mq: avoid sysfs buffer overflow by too many CPU cores Message-ID: <20190816071234.GE1368@kroah.com> References: <20190815121518.16675-1-ming.lei@redhat.com> <20190815122419.GA31891@kroah.com> <20190815122909.GA28032@ming.t460p> <20190815123535.GA29217@kroah.com> <20190815124321.GB28032@ming.t460p> <20190816024934.GA27844@ming.t460p> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190816024934.GA27844@ming.t460p> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Fri, Aug 16, 2019 at 10:49:35AM +0800, Ming Lei wrote: > On Thu, Aug 15, 2019 at 11:10:35PM +0000, Ray, Mark C (Global Solutions Engineering (GSE)) wrote: > > Hi Ming, > > > > In the customer case, the cpu_list file was not needed. It was just part of a SAP Hana script to collect all the block device data (similar to sosreport). So they were just dumping everything, and it picks up the mq-related files. > > > > I know with IRQs, we have bitmaps/mask, and can represent the list such as "0-27", without listing every CPU. I'm sure there's lots of options to address this, and getting rid of the cpu_list is one of them. > > Indeed, same with several attributes under /sys/devices/system/cpu/, > actually we can use cpumap_print_to_pagebuf() to print the CPUs. And that is changing the format of the file, which means it is obvious no one is using it, so just please delete the thing. thanks, greg k-h