[Qemu-devel] Questions about rtl8139 receive mode and debugging

[Qemu-devel] Questions about rtl8139 receive mode and debugging

[Jiang Wang]

Hi:

I am using rtl8139 nic emulation on x86 linux (CentOS 5.3). QEMU is
0.10.2  I want to set the NIC to receive the packet even if the check
sum is wrong. Is this function implemented? I searched in hw/rtl8139.c
and find a definition of "    AcceptErr = 0x20,". But it is not used
anywhere.

So I guess it may not be implemented yet. Then I try to debug this NIC
and understand its internals. But I cannot find the "printf" output
even if I put "#define DEBUG_RTL8139 1" in the source file and
recompiled the qemu.  I noticed that in this post:
http://lists.gnu.org/archive/html/qemu-devel/2006-04/msg00517.html ,
the printf seems to be able to output the message to the QEMU monitor.
But why I cannot see the printf? Is there any other settings? Thanks.

Regards,

Jiang

Re: [Qemu-devel] Questions about rtl8139 receive mode and debugging

[Igor Kovalenko]

On Tue, May 12, 2009 at 2:23 AM, Jiang Wang <jwangzju@gmail.com> wrote:
> Hi:
>
> I am using rtl8139 nic emulation on x86 linux (CentOS 5.3). QEMU is
> 0.10.2  I want to set the NIC to receive the packet even if the check
> sum is wrong. Is this function implemented? I searched in hw/rtl8139.c
> and find a definition of "    AcceptErr = 0x20,". But it is not used
> anywhere.

This mode is not implemented. Since the code overrides checksum value
for each received packet you cannot really provide it with checksum error.
Look for RTL8139_CALCULATE_RXCRC in code.

-- 
Kind regards,
Igor V. Kovalenko

Re: [Qemu-devel] Questions about rtl8139 receive mode and debugging

[Jiang Wang]

I see. I think I will just comment out "#define
RTL8139_CALCULATE_RXCRC 1" and then use  promiscuous mode. Then I
should get all the packet including the error ones. Right? Thanks.

Regards,

Jiang

On Tue, May 12, 2009 at 9:10 PM, Igor Kovalenko
<igor.v.kovalenko@gmail.com> wrote:
> On Tue, May 12, 2009 at 2:23 AM, Jiang Wang <jwangzju@gmail.com> wrote:
>> Hi:
>>
>> I am using rtl8139 nic emulation on x86 linux (CentOS 5.3). QEMU is
>> 0.10.2  I want to set the NIC to receive the packet even if the check
>> sum is wrong. Is this function implemented? I searched in hw/rtl8139.c
>> and find a definition of "    AcceptErr = 0x20,". But it is not used
>> anywhere.
>
> This mode is not implemented. Since the code overrides checksum value
> for each received packet you cannot really provide it with checksum error.
> Look for RTL8139_CALCULATE_RXCRC in code.
>
> --
> Kind regards,
> Igor V. Kovalenko
>