Re: [Qemu-devel] [PATCH RFC 0/7] Netfilter: Add each netdev a default filter

[Jason Wang]

On 01/22/2016 06:07 PM, Daniel P. Berrange wrote:
> On Fri, Jan 22, 2016 at 04:36:44PM +0800, zhanghailiang wrote:
>> This series is a prerequisite for COLO, here we add each netdev
>> a default buffer filter, it is disabled by default, and has
>> no side effect for delivering packets in net layer.
> Why can't whatever is launching QEMU just setup filters explicitly
> if they want to use COLO ? I'm not seeing an obvious compelling
> reason to add this by default and then add extra code to deal
> with special casing its behaviour.

Two things here I think. The first is the management role for COLO,
maybe it's time to discuss it now. And if management can do this, it's
ok for not implementing default filter now. Second is the default filter
itself, I still think it's not bad to have it for the future, and with
the ability to specify, change or disable the default filter. This could
simplify management and testing.

Back to this series, it mixes several things (bugs fixings, new 'status'
filed, default filter implementation, and a special handling for
filter-buffer). Better split them.

Thanks
>
>> Besides, patch 1 fixes the ouput information of 'info network' command
>> for filter.
>>
>> zhanghailiang (7):
>>   net/filter: Fix the output information for command 'info network'
>>   net/filter: Add a 'status' property for filter object
>>   net/filter: Skip the disabled filter when delivering packets
>>   net/filter: Introduce a helper to add a filter to the netdev
>>   filter-buffer: Accept zero interval
>>   net/filter: Add a default filter to each netdev
>>   net/filter: prevent the default filter to be deleted
>>
>>  include/net/filter.h |  25 +++++++-
>>  net/dump.c           |   2 -
>>  net/filter-buffer.c  |  10 ----
>>  net/filter.c         | 163 
>> +++++++++++++++++++++++++++++++++++++++++++++------
>>  net/net.c            |  27 ++++++++-
>>  5 files changed, 194 insertions(+), 33 deletions(-)
> Regards,
> Daniel