From owner-freebsd-current Tue May 28 21: 7:11 2002 Delivered-To: freebsd-current@freebsd.org Received: from evilpete.dyndns.org (12-232-26-46.client.attbi.com [12.232.26.46]) by hub.freebsd.org (Postfix) with ESMTP id ABA4337B405 for ; Tue, 28 May 2002 21:07:05 -0700 (PDT) Received: from overcee.wemm.org ([10.0.0.3]) by evilpete.dyndns.org (8.11.6/8.11.6) with ESMTP id g4T475162106 for ; Tue, 28 May 2002 21:07:05 -0700 (PDT) (envelope-from peter@wemm.org) Received: from wemm.org (localhost [127.0.0.1]) by overcee.wemm.org (Postfix) with ESMTP id A8A96380A; Tue, 28 May 2002 21:07:04 -0700 (PDT) (envelope-from peter@wemm.org) X-Mailer: exmh version 2.5 07/13/2001 with nmh-1.0.4 To: Richard Wenninger Cc: current@FreeBSD.ORG Subject: Re: UMA lock In-Reply-To: <20020529031535.CCFC3575.eros@there> Date: Tue, 28 May 2002 21:07:04 -0700 From: Peter Wemm Message-Id: <20020529040704.A8A96380A@overcee.wemm.org> Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Richard Wenninger wrote: > This is my first attempt at running "current". > > Please forgive if this question is out of line. > > After rebuilding everything, my console continually repeats this message: > > /usr/src/sys/vm/uma_core.c:1324: could sleep with "UMA lock" locked from > /usr/src/sys/vm/uma-core.c:1157 > > Should I be concerned? Excessively concerned: no. But these are all *real* problems that must be fixed. Specifically, they are holding locks while calling a function that *might* tsleep() if memory is low at the time. If it does tsleep, it will panic or otherwise lead to a deadlock or corruption. The fact that they've gone largely unnoticed until now means that it is not an urgent problem (which is why it is a warning), but if you run really low of memory you will find out just how serious it is. The bug is that things are calling things like malloc with M_WAITOK when waiting is explicitly not allowed. There are other functions that can tsleep as well that we have not added checks for yet, so this is likely just the tip of the iceberg. :-( Cheers, -Peter -- Peter Wemm - peter@wemm.org; peter@FreeBSD.org; peter@yahoo-inc.com "All of this is for nothing if we don't go to the stars" - JMS/B5 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message