lkml.org 
[lkml]   [2007]   [Feb]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: ata command timeout
Mark Lord wrote:
> I don't believe that. Command timeouts never happen on healthy systems,
> unless we have a driver bug. Okay, so I can imagine a pathological case
> of a full queue (NCQ) with all 32 commands taking longer than usual due
> to ECC retries in the firmware..

It's not quite so black and white. There have definitely been interrupt
delivery problems that cause command timeouts. Also, Intel PIIX BMDMA
(all standard PCI IDE, I think?) is defined to /not/ send an interrupt,
when a DMA error occurs. The driver is instructed to time out the
transaction, and start recovery by deducing the state of things from the
DMA status bits.

Nonetheless, I mostly agree with your statement. The two most common
causes of timeouts that I see are interrupt delivery problems, and
driver bugs.

Jeff


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

\
 
 \ /
  Last update: 2007-02-20 16:41    [W:0.099 / U:0.012 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site