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From: "Stuart MacDonald" <stuartm@connecttech.com>
To: "'Alan Cox'" <alan@lxorguk.ukuu.org.uk>,
	"'Meelis Roos'" <mroos@linux.ee>
Cc: <linux-kernel@vger.kernel.org>
Subject: RE: Serial: bug in 8250.c when handling PCI or other level triggers
Date: Thu, 15 Dec 2005 14:00:31 -0500	[thread overview]
Message-ID: <000901c601a9$d243fe50$294b82ce@stuartm> (raw)
In-Reply-To: <1134599362.25663.72.camel@localhost.localdomain>

From: On Behalf Of Alan Cox
> I don't think so. The bug as such is something I can only see being
> triggerable either by a virtual machine or by something like serious
> noise on the signal lines (eg put a 10Khz carrier on the 
> carrier detect
> line)

We found and patched this bug in one of our products. The patch was to
raise the loop counter to something more appropriate for our hardware.
The condition: the not-to-speedy embedded CPU and all ports in use.
The interrupt handler would hit the loop limit because the combination
of all ports running meant usually there was one port that needed
servicing, upping the loop count by one.

..Stu


  reply	other threads:[~2005-12-15 19:00 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-12-14 15:23 Serial: bug in 8250.c when handling PCI or other level triggers Alan Cox
2005-12-14 16:07 ` Meelis Roos
2005-12-14 17:24   ` Russell King
2005-12-14 18:43     ` Meelis Roos
2005-12-21 15:24       ` Russell King
2005-12-21 20:33     ` Meelis Roos
2005-12-21 22:15       ` Russell King
2005-12-22 10:35         ` Meelis Roos
2005-12-22 13:07           ` Russell King
2005-12-22 13:19             ` Meelis Roos
2005-12-23  9:20             ` Meelis Roos
2005-12-23  9:33               ` Russell King
2005-12-23 10:05                 ` Meelis Roos
2005-12-23 10:41                   ` Russell King
2005-12-27 13:54                     ` Meelis Roos
2005-12-28 19:55                       ` Russell King
2005-12-29  8:11                         ` Meelis Roos
2006-01-08 23:24                           ` Antonio Vargas
2006-01-09  8:54                             ` Russell King
2005-12-14 22:29   ` Alan Cox
2005-12-15 19:00     ` Stuart MacDonald [this message]
2005-12-14 16:55 ` Russell King
2005-12-14 19:08   ` Alan Cox
2005-12-14 19:55     ` Russell King

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