From owner-freebsd-bugs Fri Jan 8 20:12:43 1999 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id UAA09155 for freebsd-bugs-outgoing; Fri, 8 Jan 1999 20:12:43 -0800 (PST) (envelope-from owner-freebsd-bugs@FreeBSD.ORG) Received: from shell.futuresouth.com (shell.futuresouth.com [198.78.58.28]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id UAA09150 for ; Fri, 8 Jan 1999 20:12:41 -0800 (PST) (envelope-from fullermd@futuresouth.com) Received: (from fullermd@localhost) by shell.futuresouth.com (8.9.1a/8.9.1) id WAA27183; Fri, 8 Jan 1999 22:11:53 -0600 (CST) Message-ID: <19990108221153.B26154@futuresouth.com> Date: Fri, 8 Jan 1999 22:11:53 -0600 From: "Matthew D. Fuller" To: Nate Williams Cc: Heikki Suonsivu , kowkn@asia1.com.sg, freebsd-bugs@FreeBSD.ORG Subject: Re: i386/9341: tty-level buffer overflows References: <199901060451.UAA12400@hub.freebsd.org.newsgate.clinet.fi> <199901061636.JAA13961@mt.sri.com> <19990106132502.B25289@futuresouth.com> <199901061932.MAA16917@mt.sri.com> <19990106135449.C25289@futuresouth.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.93.2i In-Reply-To: <19990106135449.C25289@futuresouth.com>; from Matthew D. Fuller on Wed, Jan 06, 1999 at 01:54:49PM -0600 Sender: owner-freebsd-bugs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > On Wed, Jan 06, 1999 at 12:32:10PM -0700, Nate Williams woke me up to tell me: > > > > I'll bet you have crappy UARTS that claim to be 16550's, but in fact are > > some sort of clone that doesn't work well. That UARTS on my laptop are > > not real either, although I get about 57600 on it w/out problems. > > > > And, a 486/25 is not exactly a speed daemon. :) > > It's an IBM ThinkPad 350C, if that tells anyone anything. > I wouldn't be surprised at all if they were crappy UARTS, and you ain't > gotta tell ME 486/25 is slow (I run X on it, after all... ;), but c'mon; > this is *19,200* baud!! I'd think even a 486/25 should be able to handle > that without puking this much. UPDATE: Recompiled kernel with: # Serial port hacks options "TTYHOG=6140" options "RS_IBUFSIZE=3072" (This is 2.2.7) with the patches in sio.c to actually use the RS_IBUFSIZE parameter. Result: I'm now running at 38400 (twice previous speed), and even now in X I've gotten 1 overflow in the time I would have gotten easily 20 or 30 back at 19200 in syscons, even with just one ssh session going. And I'm here flipping through email, talk(1)'ing, etc. I'd say at LEAST put the option in sio.c to allow RS_IBUFSIZE to be set in the kernel config, and it probably wouldn't hurt to have the defaults a bit higher. --- *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-* | Matthew Fuller http://www.over-yonder.net/~fullermd | * fullermd@futuresouth.com fullermd@over-yonder.net * | UNIX Systems Administrator Specializing in FreeBSD | * FutureSouth Communications ISPHelp ISP Consulting * | "The only reason I'm burning my candle at both ends, | * because I haven't figured out how to light the * | middle yet" | *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-* To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-bugs" in the body of the message