Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:41768 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751772AbdJTGfl (ORCPT ); Fri, 20 Oct 2017 02:35:41 -0400 From: Kalle Valo To: Luca Coelho Cc: Marc MERLIN , linux-wireless@vger.kernel.org, linuxwifi@intel.com Subject: Re: After upgrading to 4.11.1, wifi driver refuses to load after being unloaded once. References: <20170526024826.3qjx7pe3kz44klk3@merlins.org> <1496396575.9478.54.camel@coelho.fi> <20170603165950.GC29546@merlins.org> <20170816233844.qtigfurckdr44awa@merlins.org> <20171017094440.25tpkoeyfm6q2lqw@merlins.org> <1508249157.5497.103.camel@coelho.fi> <20171017212319.eranorcigrmgcpyo@merlins.org> <1508276099.5497.122.camel@coelho.fi> <87infduk4b.fsf@purkki.adurom.net> <1508307368.5497.125.camel@coelho.fi> <87bml4iy40.fsf@kamboji.qca.qualcomm.com> <1508322176.5497.152.camel@coelho.fi> Date: Fri, 20 Oct 2017 09:35:37 +0300 In-Reply-To: <1508322176.5497.152.camel@coelho.fi> (Luca Coelho's message of "Wed, 18 Oct 2017 13:22:56 +0300") Message-ID: <8760bafhs6.fsf@kamboji.qca.qualcomm.com> (sfid-20171020_083555_586612_E9917D99) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: Luca Coelho writes: > On Wed, 2017-10-18 at 12:50 +0300, Kalle Valo wrote: >> Luca Coelho writes: >> >> > On Wed, 2017-10-18 at 07:59 +0300, Kalle Valo wrote: >> > > Luca Coelho writes: >> > > >> > > > On Tue, 2017-10-17 at 14:23 -0700, Marc MERLIN wrote: >> > > > >> > > > > I don't know how or why, but I seem to: >> > > > > saruman:~# grep IWLWIFI /boot/config-4.12.10-amd64-preempt- >> > > > > sysrq- >> > > > > 20170406 >> > > > > CONFIG_IWLWIFI=m >> > > > > CONFIG_IWLWIFI_LEDS=y >> > > > > CONFIG_IWLWIFI_OPMODE_MODULAR=y >> > > > > # CONFIG_IWLWIFI_BCAST_FILTERING is not set >> > > > > CONFIG_IWLWIFI_PCIE_RTPM=y >> > > > > CONFIG_IWLWIFI_DEBUG=y >> > > > > CONFIG_IWLWIFI_DEVICE_TRACING=y >> > > > > >> > > > > I'll remove that, thanks. >> > > > >> > > > Cool, I think that might help. If it doesn't, please report a >> > > > bug >> > > > in >> > > > buzilla. ;) >> > > >> > > But a Kconfig option should never break functionality, so IMHO >> > > this >> > > still sounds like a bug in iwlwifi. >> > >> > The problem is that to get this to work, some changes need to be >> > made >> > in the platform side. In this case, the rootport is not configured >> > properly so it won't work. >> >> Yeah, but users or distros might accidentally enable this Kconfig >> option and break the driver unintentionally. And subtle bugs like >> this >> are even worse as the user will not realise that it's because of a >> new >> Kconfig option. >> >> So I guess you can't automatically detect it the platform supports >> RTPM, >> right? Maybe there should be a module parameter which has to be set >> to >> enable this? And at least a big fat warning to the user that RTPM is >> enabled, bugs are likely and the user has to know what she's doing. > > I thought this was what EXPERT was used for: > > menuconfig EXPERT > bool "Configure standard kernel features (expert users)" > # Unhide debug options, to make the on-by-default options visible > select DEBUG_KERNEL > help > This option allows certain base kernel options and settings > to be disabled or tweaked. This is for specialized > environments which can tolerate a "non-standard" kernel. > Only use this if you really know what you are doing. > > > But it seems that it's widely used even by people/distros who don't > know what they are doing. :( Yeah, people seem to just blindly enable kconfig options. I don't blame them, there are so many options and difficult to know what to choose. > Would it be okay if we just add a printk(KERN_ERR, ...)? I think we at least we should do that, preferably even something else to prevent accidental use if the feature is so fragile. -- Kalle Valo