OK. I've applied the patch and I'm now waiting for the kernel Oops...
sometimes it takes two days until it happens.
I'm using a standard 16550A serial controller found on my hardware, that
is a PC/104 SBC:
http://www.icop.com.tw/products_detail.asp?ProductID=70
We have a custom hardware that has another serial controller (TL16C554A)
with 4 extra serial ports (also, 16550A type), and the problem happens
in a test program that is retreiving data from ttyS0 (from the SBC) and
ttyS3 (from our custom hardware).
The serial ports initialization, as reported by the kernel:
[ 15.216847] Serial: 8250/16550 driver $Revision: 1.90 $ 6 ports, IRQ
sharing disabled
[ 15.219517] serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
[ 15.221963] serial8250: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
[ 15.223907] serial8250: ttyS2 at I/O 0x3e8 (irq = 5) is a 16550A
[ 15.225757] serial8250: ttyS3 at I/O 0x2e8 (irq = 5) is a 16550A
[ 15.227644] serial8250: ttyS4 at I/O 0x1a0 (irq = 6) is a 16550A
[ 15.229656] serial8250: ttyS5 at I/O 0x1a8 (irq = 6) is a 16550A
With your patch I'm now getting the following for each iteration of my
test program:
<4>[ 298.918962] type is 4
<4>[ 298.919011] ops is c0292f00
<4>[ 298.919033] ops->startup is c01bd777
<4>[ 299.436980] type is 4
<4>[ 299.437030] ops is c0292f00
<4>[ 299.437051] ops->startup is c01bd777
I don't know if it's relevant or not but the kernel is running in
NFS-Root mode.
Best regards,
José Gonçalves
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