Re: possible Bug in IOAPIC concerning serial 8250

[Robert Hancock]

stefan verse wrote:
> Hello,
> i know, no good place to start, but my problem is a little bit
> unspecific concerning Problems with IOAPIC concerning serrial driver
> 8250 :
>
> 1. serial driver 8250 is loaded, but /dev/ttyS0 is unusable
>
> 2. hardware is a d945gclf2 mini-itx board from intel, distribution is
> easyvdr 0.6.06., Kernel Version is 2.6.29.3, serial port is activated in
> BIOS, BIOS rev LF94510J.86A.0171.2009.0403.0118
>
> dmesg reports :
> [   21.682611] Serial: 8250/16550 driver, 1 ports, IRQ sharing disabled
> [   21.682789] serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
> [   21.711689] 00:09: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
>
> and lsmod :
> 8250_pci               27412  0
> 8250_pnp               14036  0
> 8250                   20516  2 8250_pci,8250_pnp
> serial_core            18708  1 8250
>
> so driver is loaded 
>
> ls -lpr /dev/ttyS0
> crw-rw-rw- 1 root tty 4, 64 2009-06-03 07:55 /dev/ttyS0
> seems ok to me
>
> but cat < /dev/ttyS0 gives :
> cat: -: Eingabe-/Ausgabefehler                  (I/O Error)
>
> /proc/interrupts is missing driver for irq4 :

I think this is normal, the driver only claims the interrupt while the 
device is actually open. Do any dmesg messages result from trying to cat 
the device?
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/