From owner-freebsd-hackers@FreeBSD.ORG Sat Oct 4 11:41:40 2003 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id A0CB616A4B3; Sat, 4 Oct 2003 11:41:40 -0700 (PDT) Received: from ebb.errno.com (ebb.errno.com [66.127.85.87]) by mx1.FreeBSD.org (Postfix) with ESMTP id EF53B43FEA; Sat, 4 Oct 2003 11:41:39 -0700 (PDT) (envelope-from sam@errno.com) Received: from 66.127.85.91 ([66.127.85.91]) (authenticated bits=0) by ebb.errno.com (8.12.9/8.12.9) with ESMTP id h94Ifc0x002070 (version=TLSv1/SSLv3 cipher=RC4-MD5 bits=128 verify=NO); Sat, 4 Oct 2003 11:41:39 -0700 (PDT) (envelope-from sam@errno.com) From: Sam Leffler Organization: Errno Consulting To: Brian Fundakowski Feldman , hackers@freebsd.org Date: Sat, 4 Oct 2003 11:39:52 -0700 User-Agent: KMail/1.5.2 References: <200310040538.h945cDxp014188@green.bikeshed.org> In-Reply-To: <200310040538.h945cDxp014188@green.bikeshed.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200310041139.52357.sam@errno.com> Subject: Re: Is socket buffer locking as questionable as it seems? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 04 Oct 2003 18:41:40 -0000 On Friday 03 October 2003 10:38 pm, Brian Fundakowski Feldman wrote: > I keep getting these panics on my SMP box (no backtrace or DDB or crash > dump of course, because panic() == hang to FreeBSD these days): > panic: receive: m == 0 so->so_rcv.sb_cc == 52 > From what I can tell, all sorts of socket-related calls are "MP-safe" > and yet never even come close to locking the socket buffer. From > what I can tell, the easiest way for this occur would be sbrelease() > being called from somewhere that it's supposed to, but doesn't, have > sblock(). Has anyone seen these, or a place to start looking? Maybe > a way to get panics to stop hanging the machine? TIA if anyone has > some enlightenment. Haven't seen anything on my SMP test box. As Robert has already said sockets are still implicitly locked by Giant. You need to provide more information like what version you are running and what your system is doing when the panic occurs. FWIW panic does not hang for me so you might first try to figure out why that's occuring. Sam