From owner-freebsd-alpha Mon Sep 11 13: 7:55 2000 Delivered-To: freebsd-alpha@freebsd.org Received: from pike.osd.bsdi.com (pike.osd.bsdi.com [204.216.28.222]) by hub.freebsd.org (Postfix) with ESMTP id 75AA237B423 for ; Mon, 11 Sep 2000 13:07:53 -0700 (PDT) Received: (from jhb@localhost) by pike.osd.bsdi.com (8.9.3/8.9.3) id NAA60493 for freebsd-alpha@FreeBSD.org; Mon, 11 Sep 2000 13:07:52 -0700 (PDT) (envelope-from jhb) From: John Baldwin Message-Id: <200009112007.NAA60493@pike.osd.bsdi.com> Subject: Re: cvs commit: src/sys/pci pcisupport.c To: freebsd-alpha@FreeBSD.org Date: Mon, 11 Sep 2000 13:07:52 -0700 (PDT) X-Mailer: ELM [version 2.4ME+ PL68 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-alpha@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Doug Rabson wrote: > That particular panic is the one I saw before removing the calls to > mtx_enter/mtx_exit from interrupt(). I've debugged it some more and it looks like a bug somewhere in the mutex code. We are releasing the Giant lock when it is uncontested, but mtx_exit() is still calling mtx_exit_hard(), which it should only be calling for contested locks. As a result, when we try to pull a process off the blocked list so we can give it the mutex and schedule it to run, we dereference a NULL pointer. -- John Baldwin -- http://www.FreeBSD.org/~jhb/ PGP Key: http://www.cslab.vt.edu/~jobaldwi/pgpkey.asc "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-alpha" in the body of the message