linux-kernel - Re: Dropped characters in serial connection without flow control

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20091028180544.GA3523@kroah.com>
Date:	Wed, 28 Oct 2009 11:05:44 -0700
From:	Greg KH <greg@...ah.com>
To:	linux-kernel@...r.kernel.org, Alan Cox <alan@...rguk.ukuu.org.uk>
Subject: Re: Dropped characters in serial connection without flow control

On Wed, Oct 28, 2009 at 06:59:37PM +0100, Peter Stuge wrote:
> Peter Stuge wrote:
> > I'm writing a line discipline for a serial port multiplexing
> > hardware
> 
> There is no(!) support for flow control in the hardware.
> 
> Is there anything I can do to reduce serial port interrupt latency or
> otherwise try to mitigate this in my ldisc or in Linux in general? I
> realize that it will never be quite reliable without any flow
> control.

What's wrong with XON/XOFF?  That is a well-known flow control protocol
for systems without hardware support for it.

And since when is adding a UART to a hardware chip expensive these days?

thanks,

greg k-h
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/