Oren
can you please generate a small program that we can use to reproduce the bug? 
Honestly nothing comes to our mind

REgards Luca

On Oct 2, 2013, at 4:04 PM, Oren Nechushtan <[email protected]> wrote:

> Hi Luca,
>  
> One thread per RSS queue (2 in total)
> Using PF_RING aware drivers (not DNA)
> Happens also in transparent mode
>  
> # cat /proc/net/pf_ring/info
> PF_RING Version          : 5.6.0 ($Revision: exported$)
> Total rings              : 0
> Standard (non DNA) Options
> Ring slots               : 4096
> Slot version             : 15
> Capture TX               : Yes [RX+TX]
> IP Defragment            : No
> Socket Mode              : Standard
> Transparent mode         : Yes [mode 0]
> Total plugins            : 0
> Cluster Fragment Queue   : 0
> Cluster Fragment Discard : 0
> 
> Thanks,
> Oren
>  
> Date: Wed, 2 Oct 2013 15:13:57 +0200
> From: [email protected]
> To: [email protected]
> Subject: Re: [Ntop-misc] Strange pcap memory corruption
> 
> Hi Oren,
> do you have two threads per RSS queue (4 in total?), or one thread per RRS 
> queue (2 in total)?
> 
> In libpcap/PF_RING we receive packets in zero copy (see pcap-linux.c) and 
> this could explain the behaviour in case of 4 thread. Is this the case 
> perhaps?
> 
> Regards Luca
> 
> On 10/02/2013 02:32 PM, Oren Nechushtan wrote:
> Hi,
> 
> We are experiencing a strange issue with PF_RING/libpcap with the packet 
> payload changing right under the hood within the callback, without any 
> apparent reason.
> The flow is basically running two threads on eth2@0 and eth2@1 RSS queues
> 
> callBack()
> pcap_read_packet()
> pcap_read_linux()
> pcap_dispatch()
> ..
> main()
> 
> I am working on simplify and generate an example though it is not an easy 
> task.
> 
> # uname -a
> Linux ct10k 2.6.32-220.4.2.el6.i686 #1 SMP Tue Feb 14 00:24:28 GMT 2012 i686 
> i686 i386 GNU/Linux
> 
> # cat /proc/net/pf_ring/7592-eth2.49*
> Bound Device(s)    : eth2
> Active             : 1
> Breed              : Non-DNA
> Sampling Rate      : 1
> Capture Direction  : RX only
> Socket Mode        : RX+TX
> Appl. Name         : <unknown>
> IP Defragment      : No
> BPF Filtering      : Disabled
> # Sw Filt. Rules   : 0
> # Hw Filt. Rules   : 0
> Poll Pkt Watermark : 1
> Num Poll Calls     : 0
> Channel Id Mask    : 0x00000001
> Cluster Id         : 0
> Slot Version       : 15 [5.6.0]
> Min Num Slots      : 5399
> Bucket Len         : 1519
> Slot Len           : 1552 [bucket+header]
> Tot Memory         : 8388608
> Tot Packets        : 639755
> Tot Pkt Lost       : 362816
> Tot Insert         : 276939
> Tot Read           : 268808
> Insert Offset      : 2594936
> Remove Offset      : 2597608
> TX: Send Ok        : 0
> TX: Send Errors    : 0
> Reflect: Fwd Ok    : 0
> Reflect: Fwd Errors: 0
> Num Free Slots     : 0
> Bound Device(s)    : eth2
> Active             : 1
> Breed              : Non-DNA
> Sampling Rate      : 1
> Capture Direction  : RX only
> Socket Mode        : RX+TX
> Appl. Name         : <unknown>
> IP Defragment      : No
> BPF Filtering      : Disabled
> # Sw Filt. Rules   : 0
> # Hw Filt. Rules   : 0
> Poll Pkt Watermark : 1
> Num Poll Calls     : 0
> Channel Id Mask    : 0x00000002
> Cluster Id         : 0
> Slot Version       : 15 [5.6.0]
> Min Num Slots      : 5399
> Bucket Len         : 1519
> Slot Len           : 1552 [bucket+header]
> Tot Memory         : 8388608
> Tot Packets        : 619081
> Tot Pkt Lost       : 124764
> Tot Insert         : 494317
> Tot Read           : 481677
> Insert Offset      : 7515736
> Remove Offset      : 5550312
> TX: Send Ok        : 0
> TX: Send Errors    : 0
> Reflect: Fwd Ok    : 0
> Reflect: Fwd Errors: 0
> Num Free Slots     : 0
>  
> [root@ct10k forescout]# ethtool -i eth2
> driver: ixgbe
> version: 3.11.33
> firmware-version: 0x800000cb
> bus-info: 0000:06:00.0
> supports-statistics: yes
> supports-test: yes
> supports-eeprom-access: yes
> supports-register-dump: yes
>  
> A potential hint is that the issue correlates with being at the end of the 
> ring, e.g.,
>  
> (gdb) p bp-handle->ring->buffer
> $2 = 8386304
>  
> Any advice would be welcome,
> 
> Best,
> Oren
>  
> 
> 
> _______________________________________________
> Ntop-misc mailing list
> [email protected]
> http://listgateway.unipi.it/mailman/listinfo/ntop-misc
> 
> 
> _______________________________________________ Ntop-misc mailing list 
> [email protected] 
> http://listgateway.unipi.it/mailman/listinfo/ntop-misc
> _______________________________________________
> Ntop-misc mailing list
> [email protected]
> http://listgateway.unipi.it/mailman/listinfo/ntop-misc

_______________________________________________
Ntop-misc mailing list
[email protected]
http://listgateway.unipi.it/mailman/listinfo/ntop-misc

Reply via email to