From owner-freebsd-hackers@FreeBSD.ORG Fri Apr 20 18:16:46 2012 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 7561C1065674; Fri, 20 Apr 2012 18:16:46 +0000 (UTC) (envelope-from lacombar@gmail.com) Received: from mail-vb0-f54.google.com (mail-vb0-f54.google.com [209.85.212.54]) by mx1.freebsd.org (Postfix) with ESMTP id 1F90F8FC22; Fri, 20 Apr 2012 18:16:46 +0000 (UTC) Received: by vbmv11 with SMTP id v11so9256185vbm.13 for ; Fri, 20 Apr 2012 11:16:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:date:message-id:subject:from:to:content-type; bh=nMepNO5cmPZXV5xvNYsEW0OnvvtNK9hGqtPqBmYXmc4=; b=RklNCrq6R11JoMtu320kqp73904Fu2wgdHh0jSoSmcGyA3yAMLZUApsDhfR2zMP5OI 4Sl65lJLQPpreQvJue8jLpQQDw3h295PM/rFLCAb/Xoko19ppcBz5LZBqKs6LQ8ZE8pY WVrhSN1B1pHDpCZGsNdLvvhVCWTeF5i8F0WkOjpPz2b8I6wcQwSSLUSGgZ3eMVS7+hKk Vh3bWkCnuqJdDLQLuXdXrhmDfVL5ereFgW9vTl7hXzoBONIs+dMMtNC0b45yR0op5Nsb 5oSqyqOpNHgmDiqUt7POD1tli1ANzS9aNXpXuSdslfCHsK+luct1gnsmGtY1WS7Tmph9 pSaA== MIME-Version: 1.0 Received: by 10.220.156.10 with SMTP id u10mr814327vcw.20.1334945805489; Fri, 20 Apr 2012 11:16:45 -0700 (PDT) Received: by 10.220.18.16 with HTTP; Fri, 20 Apr 2012 11:16:45 -0700 (PDT) Date: Fri, 20 Apr 2012 14:16:45 -0400 Message-ID: From: Arnaud Lacombe To: FreeBSD Hackers , FreeBSD Current Content-Type: text/plain; charset=ISO-8859-1 Cc: Subject: Disabling an arbitrary device X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 20 Apr 2012 18:16:46 -0000 Hi, I will be bringing up an old thread there, but it would seem the situation did not evolve in the past 9 years. I have a machine running 7.1 whose UHCI controller is generating some interrupt storm: # vmstat -i interrupt total rate irq4: sio0 1328 2 irq19: uhci1+ 63514509 96380 [...] generating useless load on one CPU: # top -SH last pid: 5223; load averages: 0.00, 0.00, 0.00 up 0+00:17:21 13:10:35 117 processes: 14 running, 79 sleeping, 24 waiting CPU: 0.2% user, 0.0% nice, 0.2% system, 6.6% interrupt, 93.0% idle Mem: 33M Active, 9348K Inact, 67M Wired, 400K Cache, 29M Buf, 2892M Free [...] 57 root -64 - 0K 8K CPU0 0 11:59 86.57% irq19: uhci1+ I thought I could use an hint to forbid uhci(4) attachment, ala: hint.uhci.0.disabled="1" hint.uhci.1.disabled="1" in /boot/loader.conf. However, it would seem that what should be usable with any arbitrary devices, ie. be an integral part of device(9), has to be hardcoded in every driver, sad. - Arnaud ps: the original thread I found is from September 2004: http://lists.freebsd.org/pipermail/freebsd-questions/2004-September/058717.html