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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 97AFCC35666 for ; Sat, 22 Feb 2020 15:41:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 64805206ED for ; Sat, 22 Feb 2020 15:41:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Pgu+gYaD" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727864AbgBVPlW (ORCPT ); Sat, 22 Feb 2020 10:41:22 -0500 Received: from mail-pl1-f194.google.com ([209.85.214.194]:33382 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727230AbgBVPlV (ORCPT ); Sat, 22 Feb 2020 10:41:21 -0500 Received: by mail-pl1-f194.google.com with SMTP id ay11so2168986plb.0; Sat, 22 Feb 2020 07:41:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=ZKqnhKtnjlrm/NrpyM5QaS9UL8/A0/pvxGGFI8Wsv3o=; b=Pgu+gYaDPETaF85sNjWfDPiAD6EkDxAO6E9xek1rU5M6uwrNQN13L3OMjjvwiPxDoe gp49QnHzOchd1YoaxN/JosfktWZFqyf/pV5JScPo+95BIbujN1wTPRaAsX2HGOHpASmG UzrvvEAy2gZ9ddMNJfWXCse+uP9NdXWuN2uqQ4B7RFbnVMdfeFQyFx6UHwi6xBTO6vqP TUWuBZ4qN5wJAo0WeeVPDrlHANL/sbbVl1wut/om3pYofISgu2DFAqWO2dDXENljZckj 1ugcPNB6OUHLG23KAG2eHjzujmB4nPLqGnfPe8YLLPAZEjJTUkpK9foURb2yHjwdm7ue XMKg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:subject:to:cc:references:from:message-id :date:user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=ZKqnhKtnjlrm/NrpyM5QaS9UL8/A0/pvxGGFI8Wsv3o=; b=c6xdj2CfQENiUAe74mRONG/chuTE7G3pbJCKfzCKurPwFEAeNx+zlW+Q44QlxrBPCE wBUNoDhoVJw276QnFhAthPvpF3z1kANkH0N4RRanpxntjY7K0iAdR50yO9n0b9GG8/p5 8M4DFBuGsjElLpZevfWSoQUXHqqsznLNscO3ImqmBDC+KXKe2Giv8qOL5vY0Den4Lr4w rnFDwvjxq2GIPbw4TEUSWgq1NIjSR1wHYuwfLXEFWZM8b6MeLXNvnegw71BrV+5V0Bgh Y5TLY5msyUBAqtckbgNhUCAG+KoBlYgxsjU+XP7aU8Nh53rsvIMkpAQ++2qY0pyeiapu rSLg== X-Gm-Message-State: APjAAAVpjkWL+TnNNKt3FaJ6bP1Tjtz4eAS6KKHb9afeKfaSiTX6rdIe 2yTl6RuqpBSh+T/Tm+d5tS2+r2ay X-Google-Smtp-Source: APXvYqxQm22B+SJe7ymcheyrXUZZA2F9Z0qnG9iBS9cXm58rL50yqAHe+Sb+plQX+1/lnt4E7jPOEg== X-Received: by 2002:a17:90a:17e5:: with SMTP id q92mr10137107pja.28.1582386080725; Sat, 22 Feb 2020 07:41:20 -0800 (PST) Received: from server.roeck-us.net ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id r8sm6230930pjo.22.2020.02.22.07.41.19 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 22 Feb 2020 07:41:19 -0800 (PST) Subject: Re: [regression] nct6775 does not load in 5.4 and 5.5, bisected to b84398d6d7f90080 To: Martin Volf , Mika Westerberg , Jean Delvare , Wolfram Sang Cc: linux-i2c@vger.kernel.org, linux-hwmon@vger.kernel.org, Linux Kernel Mailing List References: From: Guenter Roeck Message-ID: <1bdbac08-86f8-2a57-2b0d-8cd2beb2a1c0@roeck-us.net> Date: Sat, 22 Feb 2020 07:41:18 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/22/20 3:13 AM, Martin Volf wrote: > Hello, > > hardware monitoring sensors NCT6796D on my Asus PRIME Z390M-PLUS > motherboard with Intel i7-9700 CPU don't work with 5.4 and newer linux > kernels, the driver nct6775 does not load. > > It is working OK in version 5.3. I have used almost all released stable > versions from 5.3.8 to 5.3.16; I didn't try older kernels. > > Even on new kernels the sensors-detect finds the sensors: > Found `Nuvoton NCT6796D Super IO Sensors' Success! > (address 0x290, driver `nct6775') > but "modprobe nct6775" says: > ERROR: could not insert 'nct6775': No such device > There is nothing interesting in dmesg. > My wild guess would be that the i801 driver is a bit aggressive with reserving memory spaces, but I don't immediately see what it does differently in that regard after the offending patch. Does it work if you unload the i2c_i801 driver first ? You could also try to compare the output of /proc/ioports with the old and the new kernel, and see if the IO address space used by nct6775 in v5.3 is assigned to the i801 driver (or some other driver, such as the watchdog driver) in v5.4. If you are into hacking the kernel, you could also add some debug messages into the nct6775 driver to find out where exactly it fails. If that helps, maybe we can then add those messages into into the driver source to help others if this is observed again. Thanks, Guenter