From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH] libata-eh: Use switch() instead of sparse array for protocol strings Date: Mon, 9 Jan 2017 14:41:00 -0500 Message-ID: <20170109194100.GH12827@mtj.duckdns.org> References: <1483973368-6828-1-git-send-email-geert@linux-m68k.org> <20170109152319.GA12827@mtj.duckdns.org> <20170109160424.GB12827@mtj.duckdns.org> <20170109172723.GA30423@infradead.org> <20170109173154.GE12827@mtj.duckdns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-qk0-f196.google.com ([209.85.220.196]:35719 "EHLO mail-qk0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S969056AbdAITlH (ORCPT ); Mon, 9 Jan 2017 14:41:07 -0500 Content-Disposition: inline In-Reply-To: Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Geert Uytterhoeven Cc: Christoph Hellwig , "linux-ide@vger.kernel.org" , "linux-kernel@vger.kernel.org" Hello, Geert. On Mon, Jan 09, 2017 at 07:25:31PM +0100, Geert Uytterhoeven wrote: > On Mon, Jan 9, 2017 at 6:31 PM, Tejun Heo wrote: > > On Mon, Jan 09, 2017 at 09:27:23AM -0800, Christoph Hellwig wrote: > >> On Mon, Jan 09, 2017 at 05:30:02PM +0100, Geert Uytterhoeven wrote: > >> > > ata_force_param_buf is __initdata and shouldn't really matter. > >> > > >> > It mainly matters because of e.g. bootloader limitations. > >> > >> Do we need a full 4k for the force parameters? What would a typical > >> command line for it look like? > > > > Maybe a couple hundreds bytes at max, but it's a bit weird to restrict > > this given that it is bss, not gigantic and __initdata. What kind of > > bootloader limitations are we talking about? > > Some boot loaders start overwriting themselves or the passed DTB if the > kernel becomes too big. > If I'm not mistaken, bss is still expanded early (verified, increasing bss > can trigger the above problem). So, to avoid that, we can just kmalloc and kfree the buffer, but it seems like a silly complication to work around bugs in some bootloaders. There are many places in kernel where we're liberal about __initdata which is great. I'm not sure complicating all those places for a broken bootloader is a good idea. Thanks. -- tejun