From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id 6CC28DDEB8 for ; Tue, 27 Feb 2007 17:48:44 +1100 (EST) Subject: Re: Make sure we populate the initroot filesystem late enough From: Benjamin Herrenschmidt To: Linus Torvalds In-Reply-To: References: <1172462466.3971.46.camel@shinybook.infradead.org> <35684e789e5c2447eab393c8946efcb9@bga.com> <1172523468.3560.2.camel@shinybook.infradead.org> Content-Type: text/plain Date: Tue, 27 Feb 2007 07:46:39 +0100 Message-Id: <1172558799.11949.41.camel@localhost.localdomain> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org, David Woodhouse , LKML , Milton Miller List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , > USB controller issues? We used to have these really hard-to-debug problems > with the USB controller being active and having had the BIOS set up the > command queues etc. Really subtle. It's why we now have PCI quirks for > shutting up (most) USB controllers very early. On powermacs or powerbooks, the USB controller is shut down by the firmware when we call the "quiesce" OF call from prom_init.c, which happens before the kernel relocates itself to 0 and takes over memory. Unless we fucked up something in there, I wouldn't expect that to be the cause. > If there is some USB controller that we miss, or that sets up its command > chain to some unexpected area (so that USB is active and corrupting memory > even very early on), that could explain it. Did we setup the OHCI controller when the crash happen ? Maybe we broke something subtle in the USB stack ? Ben.