From owner-freebsd-bugs Thu Apr 9 21:40:17 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id VAA05663 for freebsd-bugs-outgoing; Thu, 9 Apr 1998 21:40:17 -0700 (PDT) (envelope-from owner-freebsd-bugs@FreeBSD.ORG) Received: (from gnats@localhost) by hub.freebsd.org (8.8.8/8.8.8) id VAA05600; Thu, 9 Apr 1998 21:40:05 -0700 (PDT) (envelope-from gnats) Date: Thu, 9 Apr 1998 21:40:05 -0700 (PDT) Message-Id: <199804100440.VAA05600@hub.freebsd.org> To: freebsd-bugs Cc: From: "Justin T. Gibbs" Subject: Re: kern/6258: FreeBSD-2.2.6 VM lockup on kernel map due to brelse calling bfreekva(), dump lockup in getnewbuf() due to fragmented buffer_map Reply-To: "Justin T. Gibbs" Sender: owner-freebsd-bugs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org The following reply was made to PR kern/6258; it has been noted by GNATS. From: "Justin T. Gibbs" To: dillon@best.net Cc: FreeBSD-gnats-submit@freebsd.org Subject: Re: kern/6258: FreeBSD-2.2.6 VM lockup on kernel map due to brelse calling bfreekva(), dump lockup in getnewbuf() due to fragmented buffer_map Date: Thu, 09 Apr 1998 22:26:18 -0600 > Problem #1: Kernel locks up in kernel map due to brelse() calling > bfreekva() from a SCSI interrupt while kernel map is already locked > (there was another bugtrack on this problem). The fix for this was > to defer calling bfreekva(). Perhaps this can be addressed by simply delaying the call only until the vm SWI can run. I added a vm SWI for the bus dma stuff, but it could easily be expanded to perform this task as well. I would expect us to hit the SWI rapidly in most cases, thereby preventing fragmentation. -- Justin To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-bugs" in the body of the message