The application shall be used in the hospitals, which due to permanent lack
of money use very old hardware - so RS are offen 16450 based (no input
FIFO), IDE controllers use only PIO mode and so on.
I'm pretty sure, that there are more people who experience that problem.
I think that the first proposed solution (marking of overrun in the data
stream, when PARMRK flag is set) does not increase seriously the size of
driver's code, and should be safe for other applications (the sequence
0xff 0x01 has no meaning when PARMRK flag is used, so can be used for
marking of overrun event).
> That's why currently the overrun case is treated as a system log; it's
> an indication that system isn't setup correctly, or that there's a
> kernel problem. In practice overruns should never happen. The most
> common case of overruns is due to the IDE device driver taking too
> long. Read the man page about hdparm's -u option, and try it. It
> will likely cause your overrun problem to go away altogether.
>
> I'll think about adding your suggestions, but our time is almost
> certain better spent trying to fix why the overrun's are happening in
> the first place, rather than trying to improve ways that the application
> is notified of the fact that something had gone wrong. Let's rather
> concentrate on avoiding things from going wrong in the first place.
I agree, but Linux is often used on very old hardware (unusable with other
contemporary OS's) and I have at least one computer, where there was no way
to avoid overruns at 115200 (386/40MHz, 8MB RAM, IDE-PIO). The possibility
of using such old hardware is one of big advatages of Linux (that's why
most distributions still contain mainly binaries compiled for i386).
The information about the overrun in the logfile may be easily overlooked...
-- Thanks for all the answers Wojciech M. Zabolotny http://www.ise.pw.edu.pl/~wzab wzab@ise.pw.edu.pl- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/