From owner-freebsd-alpha Wed Nov 6 20:58: 0 2002 Delivered-To: freebsd-alpha@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 5F3B437B401; Wed, 6 Nov 2002 20:57:59 -0800 (PST) Received: from eumenes.hosting.swbell.net (eumenes.hosting.swbell.net [216.100.98.7]) by mx1.FreeBSD.org (Postfix) with ESMTP id E7C1A43E42; Wed, 6 Nov 2002 20:57:58 -0800 (PST) (envelope-from alc@imimic.com) Received: from imimic.com (adsl-216-63-78-19.dsl.hstntx.swbell.net [216.63.78.19]) by eumenes.hosting.swbell.net id XAA23022; Wed, 6 Nov 2002 23:57:31 -0500 (EST) [ConcentricHost SMTP Relay 1.14] Message-ID: <3DC9F2B9.50B0B8E4@imimic.com> Date: Wed, 06 Nov 2002 22:57:29 -0600 From: "Alan L. Cox" Organization: iMimic Networking, Inc. X-Mailer: Mozilla 4.8 [en] (X11; U; Linux 2.4.2 i386) X-Accept-Language: en MIME-Version: 1.0 To: Jeff Roberson Cc: Matthew Jacob , jeff@freebsd.org, alpha@freebsd.org, alc@freebsd.org, jhb@freebsd.org Subject: Re: alpha: top of tree kernel blooie References: <20021106181122.K1374-100000@mail.chesapeake.net> Content-Type: text/plain; charset=x-user-defined Content-Transfer-Encoding: 7bit Sender: owner-freebsd-alpha@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org Jeff Roberson wrote: > ... > Alan, do you have any ideas? This particular code path is heavily exercised; and I haven't heard of any similar panics on x86-based systems. These observations make me wonder if there isn't a missing memory barrier between a uma_dbg_alloc() on one CPU and the uma_dbg_free() that's panicing on the other CPU. In other words, how are accesses to us_freelist[] being synchronized? Alan To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-alpha" in the body of the message