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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 CA102C433B4 for ; Thu, 29 Apr 2021 20:14:40 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7CD49613E1 for ; Thu, 29 Apr 2021 20:14:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7CD49613E1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=thesusis.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.120208.227331 (Exim 4.92) (envelope-from ) id 1lcD37-0006je-4P; Thu, 29 Apr 2021 20:14:13 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 120208.227331; Thu, 29 Apr 2021 20:14:13 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lcD37-0006jX-1R; Thu, 29 Apr 2021 20:14:13 +0000 Received: by outflank-mailman (input) for mailman id 120208; Thu, 29 Apr 2021 20:14:12 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lcD36-0006jS-5f for xen-devel@lists.xenproject.org; Thu, 29 Apr 2021 20:14:12 +0000 Received: from vps.thesusis.net (unknown [34.202.238.73]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 38c3b407-288e-4d0a-8f6b-7d62307723de; Thu, 29 Apr 2021 20:14:11 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by vps.thesusis.net (Postfix) with ESMTP id 201FE2EC90; Thu, 29 Apr 2021 16:14:11 -0400 (EDT) Received: from vps.thesusis.net ([IPv6:::1]) by localhost (vps.thesusis.net [IPv6:::1]) (amavisd-new, port 10024) with ESMTP id 89QMLZuC1OIo; Thu, 29 Apr 2021 16:14:10 -0400 (EDT) Received: by vps.thesusis.net (Postfix, from userid 1000) id D9C722ECB9; Thu, 29 Apr 2021 16:14:10 -0400 (EDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 38c3b407-288e-4d0a-8f6b-7d62307723de References: <87o8dw52jc.fsf@vps.thesusis.net> User-agent: mu4e 1.5.7; emacs 26.3 From: Phillip Susi To: xen-devel@lists.xenproject.org Cc: linux-input@vger.kernel.org, dmitry.torokhov@gmail.com Subject: Re: Xen Virtual Keyboard modalias breaking uevents Date: Thu, 29 Apr 2021 16:10:09 -0400 In-reply-to: <87o8dw52jc.fsf@vps.thesusis.net> Message-ID: <87fsz84zn1.fsf@vps.thesusis.net> MIME-Version: 1.0 Content-Type: text/plain It appears that input/input.c is responsible for the insane modalias length. If I am reading input_print_modalias() correctly, it appends a "k" plus every key code that the keyboard supports, and the Xen Virtual Keyboard supports a lot of keycodes. Why does it do this? Phillip Susi writes: > So I have finally drilled down to the modalias for the Xen Virtual > Keyboard driver being so long ( over 2KB ) that it causes an -ENOMEM > when trying to add it to the environment for uevents. This causes > coldplug to fail, which causes the script doing coldplug as part of the > debian-installer init to fail, which causes a kernel panic when init > exits, which then for reasons I have yet to understand, causes the Xen > domU to reboot. > > Why is this modalias so huge? Can we pare it down, or or is there > another solution to get uevents working on this device again? Maybe the > environment block size needs to be increased? I don't know.