From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] Fix interface autodetection in legacy IDE driver (trial #2) Date: Tue, 27 Dec 2016 11:41:12 -0500 (EST) Message-ID: <20161227.114112.712597535585873594.davem@davemloft.net> References: <3010789.Juyl7C8p5j@amdc3058> <6997612.Sd3D1QNmYZ@amdc3058> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:38388 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754145AbcL0QlO (ORCPT ); Tue, 27 Dec 2016 11:41:14 -0500 In-Reply-To: <6997612.Sd3D1QNmYZ@amdc3058> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: b.zolnierkie@samsung.com Cc: lramos.prof@yahoo.com.br, linux-ide@vger.kernel.org, petkovbb@gmail.com From: Bartlomiej Zolnierkiewicz Date: Tue, 27 Dec 2016 17:06:19 +0100 > On Tuesday, December 27, 2016 11:08:24 AM Bartlomiej Zolnierkiewicz wrote: >> >> Hi, >> >> On Monday, December 26, 2016 11:47:24 AM David Miller wrote: >> > From: Luiz Carlos Ramos >> > Date: Tue, 11 Oct 2016 22:12:45 -0300 >> > >> > > This humble patch was sent one or two months before, and had no actions, >> > > except for a colleague reply which friendly pointed out some formatting >> > > problems (which were solved in a second message). >> > > >> > > It relates to an old code, the legacy IDE driver, but the bug it >> > > addresses is real. The code, although rarely used, is >> > > still there to be compiled if one chooses to do so (like me). >> > > >> > > Also, the fix has a very low risk of present collateral effects IMHO. >> > > It is already compiled and tested in some embedded machines. >> > > >> > > So, again IMHO, it is worth be fixed. >> > > >> > > This email is a second trial with it. I hope it can help the one or two >> > > guys out there which are still running the legacy IDE driver and >> > > haven't noticed the former email. >> > > >> > > Best regards, >> > > >> > > Signed-off-by: Luiz Carlos Ramos >> > >> > This bug was introduced by commit >> > 20df429dd6671804999493baf2952f82582869fa ("ide-generic: handle probing >> > of legacy io-ports v5") which seems poorly tested. >> >> Please always cc: the original commit author. >> >> > Applied and queued up for -stable, th anks. >> >> For some reason I've never got the discussed patch from >> linux-ide ML though I now have found in the patchwork: >> >> https://patchwork.ozlabs.org/patch/680975/ >> >> The patch is incorrect. If you have PCI IDE devices (like in >> the case described in the situation being "fixed" by the patch) >> you should use the correct PCI IDE host driver for proper >> operation and not ide-generic host driver (the latter still can >> be used by using kernel parameters). > > Moreover this patch introduces a regression. In the situation > when there are no PCI IDE devices and the probing should be done > automatically (for the first two legacy IDE ports) it will be no > longer done. > > Now back to the using correct PCI IDE host drivers - Luiz what > are the systems that you need this patch on? Could you please > get 'lspci -nn' command output from them? The original code before the patch in question probed the interfaces unconditionally, probe_mask was a static int set to "0x03". Commit 20df429dd6671804999493baf2952f82582869fa changed the default behavior, as well as adding a new module parameter whose behavior makes no sense at all. Inverted bit logic? Give me a break. Sorry, no, the fix is correct and I'm pushing it to Linus.