* [PATCH net] i40e: report VF tx_dropped with tx_errors instead of tx_discards
@ 2025-06-18 19:52 Dennis Chen
2025-06-30 16:49 ` Simon Horman
2025-07-17 16:46 ` Dennis Chen
0 siblings, 2 replies; 6+ messages in thread
From: Dennis Chen @ 2025-06-18 19:52 UTC (permalink / raw)
To: netdev
Cc: anthony.l.nguyen, przemyslaw.kitszel, andrew+netdev, davem,
edumazet, kuba, pabeni, intel-wired-lan, Dennis Chen
Currently the tx_dropped field in VF stats is not updated correctly
when reading stats from the PF. This is because it reads from
i40e_eth_stats.tx_discards which seems to be unused for per VSI stats,
as it is not updated by i40e_update_eth_stats() and the corresponding
register, GLV_TDPC, is not implemented[1].
Use i40e_eth_stats.tx_errors instead, which is actually updated by
i40e_update_eth_stats() by reading from GLV_TEPC.
To test, create a VF and try to send bad packets through it:
$ echo 1 > /sys/class/net/enp2s0f0/device/sriov_numvfs
$ cat test.py
from scapy.all import *
vlan_pkt = Ether(dst="ff:ff:ff:ff:ff:ff") / Dot1Q(vlan=999) / IP(dst="192.168.0.1") / ICMP()
ttl_pkt = IP(dst="8.8.8.8", ttl=0) / ICMP()
print("Send packet with bad VLAN tag")
sendp(vlan_pkt, iface="enp2s0f0v0")
print("Send packet with TTL=0")
sendp(ttl_pkt, iface="enp2s0f0v0")
$ ip -s link show dev enp2s0f0
16: enp2s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
link/ether 3c:ec:ef:b7:e0:ac brd ff:ff:ff:ff:ff:ff
RX: bytes packets errors dropped missed mcast
0 0 0 0 0 0
TX: bytes packets errors dropped carrier collsns
0 0 0 0 0 0
vf 0 link/ether e2:c6:fd:c1:1e:92 brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state auto, trust off
RX: bytes packets mcast bcast dropped
0 0 0 0 0
TX: bytes packets dropped
0 0 0
$ python test.py
Send packet with bad VLAN tag
.
Sent 1 packets.
Send packet with TTL=0
.
Sent 1 packets.
$ ip -s link show dev enp2s0f0
16: enp2s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
link/ether 3c:ec:ef:b7:e0:ac brd ff:ff:ff:ff:ff:ff
RX: bytes packets errors dropped missed mcast
0 0 0 0 0 0
TX: bytes packets errors dropped carrier collsns
0 0 0 0 0 0
vf 0 link/ether e2:c6:fd:c1:1e:92 brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state auto, trust off
RX: bytes packets mcast bcast dropped
0 0 0 0 0
TX: bytes packets dropped
0 0 0
A packet with non-existent VLAN tag and a packet with TTL = 0 are sent,
but tx_dropped is not incremented.
After patch:
$ ip -s link show dev enp2s0f0
19: enp2s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
link/ether 3c:ec:ef:b7:e0:ac brd ff:ff:ff:ff:ff:ff
RX: bytes packets errors dropped missed mcast
0 0 0 0 0 0
TX: bytes packets errors dropped carrier collsns
0 0 0 0 0 0
vf 0 link/ether 4a:b7:3d:37:f7:56 brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state auto, trust off
RX: bytes packets mcast bcast dropped
0 0 0 0 0
TX: bytes packets dropped
0 0 2
Fixes: dc645daef9af5bcbd9c ("i40e: implement VF stats NDO")
Signed-off-by: Dennis Chen <dechen@redhat.com>
Link: https://www.intel.com/content/www/us/en/content-details/596333/intel-ethernet-controller-x710-tm4-at2-carlsville-datasheet.html
---
drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
index 88e6bef69342..2dbe38eb9494 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
@@ -5006,7 +5006,7 @@ int i40e_get_vf_stats(struct net_device *netdev, int vf_id,
vf_stats->broadcast = stats->rx_broadcast;
vf_stats->multicast = stats->rx_multicast;
vf_stats->rx_dropped = stats->rx_discards + stats->rx_discards_other;
- vf_stats->tx_dropped = stats->tx_discards;
+ vf_stats->tx_dropped = stats->tx_errors;
return 0;
}
--
2.49.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH net] i40e: report VF tx_dropped with tx_errors instead of tx_discards
2025-06-18 19:52 [PATCH net] i40e: report VF tx_dropped with tx_errors instead of tx_discards Dennis Chen
@ 2025-06-30 16:49 ` Simon Horman
2025-07-21 9:46 ` [Intel-wired-lan] " Romanowski, Rafal
2025-07-17 16:46 ` Dennis Chen
1 sibling, 1 reply; 6+ messages in thread
From: Simon Horman @ 2025-06-30 16:49 UTC (permalink / raw)
To: Dennis Chen
Cc: netdev, anthony.l.nguyen, przemyslaw.kitszel, andrew+netdev,
davem, edumazet, kuba, pabeni, intel-wired-lan
On Wed, Jun 18, 2025 at 03:52:40PM -0400, Dennis Chen wrote:
> Currently the tx_dropped field in VF stats is not updated correctly
> when reading stats from the PF. This is because it reads from
> i40e_eth_stats.tx_discards which seems to be unused for per VSI stats,
> as it is not updated by i40e_update_eth_stats() and the corresponding
> register, GLV_TDPC, is not implemented[1].
>
> Use i40e_eth_stats.tx_errors instead, which is actually updated by
> i40e_update_eth_stats() by reading from GLV_TEPC.
...
> Fixes: dc645daef9af5bcbd9c ("i40e: implement VF stats NDO")
> Signed-off-by: Dennis Chen <dechen@redhat.com>
> Link: https://www.intel.com/content/www/us/en/content-details/596333/intel-ethernet-controller-x710-tm4-at2-carlsville-datasheet.html
Hi Dennis,
Thanks for the detailed explanation, it's very much appreciated.
One minor nit, is that there are some leading spaces before "Link: "
a few lines above. But I suspect you don't need to repost just to
address that.
Reviewed-by: Simon Horman <horms@kernel.org>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH net] i40e: report VF tx_dropped with tx_errors instead of tx_discards
2025-06-18 19:52 [PATCH net] i40e: report VF tx_dropped with tx_errors instead of tx_discards Dennis Chen
2025-06-30 16:49 ` Simon Horman
@ 2025-07-17 16:46 ` Dennis Chen
2025-07-17 20:05 ` Tony Nguyen
1 sibling, 1 reply; 6+ messages in thread
From: Dennis Chen @ 2025-07-17 16:46 UTC (permalink / raw)
To: netdev
Cc: anthony.l.nguyen, przemyslaw.kitszel, andrew+netdev, davem,
edumazet, kuba, pabeni, intel-wired-lan
On Wed, Jun 18, 2025 at 3:52 PM Dennis Chen <dechen@redhat.com> wrote:
>
> Currently the tx_dropped field in VF stats is not updated correctly
> when reading stats from the PF. This is because it reads from
> i40e_eth_stats.tx_discards which seems to be unused for per VSI stats,
> as it is not updated by i40e_update_eth_stats() and the corresponding
> register, GLV_TDPC, is not implemented[1].
>
> Use i40e_eth_stats.tx_errors instead, which is actually updated by
> i40e_update_eth_stats() by reading from GLV_TEPC.
>
> To test, create a VF and try to send bad packets through it:
>
> $ echo 1 > /sys/class/net/enp2s0f0/device/sriov_numvfs
> $ cat test.py
> from scapy.all import *
>
> vlan_pkt = Ether(dst="ff:ff:ff:ff:ff:ff") / Dot1Q(vlan=999) / IP(dst="192.168.0.1") / ICMP()
> ttl_pkt = IP(dst="8.8.8.8", ttl=0) / ICMP()
>
> print("Send packet with bad VLAN tag")
> sendp(vlan_pkt, iface="enp2s0f0v0")
> print("Send packet with TTL=0")
> sendp(ttl_pkt, iface="enp2s0f0v0")
> $ ip -s link show dev enp2s0f0
> 16: enp2s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
> link/ether 3c:ec:ef:b7:e0:ac brd ff:ff:ff:ff:ff:ff
> RX: bytes packets errors dropped missed mcast
> 0 0 0 0 0 0
> TX: bytes packets errors dropped carrier collsns
> 0 0 0 0 0 0
> vf 0 link/ether e2:c6:fd:c1:1e:92 brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state auto, trust off
> RX: bytes packets mcast bcast dropped
> 0 0 0 0 0
> TX: bytes packets dropped
> 0 0 0
> $ python test.py
> Send packet with bad VLAN tag
> .
> Sent 1 packets.
> Send packet with TTL=0
> .
> Sent 1 packets.
> $ ip -s link show dev enp2s0f0
> 16: enp2s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
> link/ether 3c:ec:ef:b7:e0:ac brd ff:ff:ff:ff:ff:ff
> RX: bytes packets errors dropped missed mcast
> 0 0 0 0 0 0
> TX: bytes packets errors dropped carrier collsns
> 0 0 0 0 0 0
> vf 0 link/ether e2:c6:fd:c1:1e:92 brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state auto, trust off
> RX: bytes packets mcast bcast dropped
> 0 0 0 0 0
> TX: bytes packets dropped
> 0 0 0
>
> A packet with non-existent VLAN tag and a packet with TTL = 0 are sent,
> but tx_dropped is not incremented.
>
> After patch:
>
> $ ip -s link show dev enp2s0f0
> 19: enp2s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
> link/ether 3c:ec:ef:b7:e0:ac brd ff:ff:ff:ff:ff:ff
> RX: bytes packets errors dropped missed mcast
> 0 0 0 0 0 0
> TX: bytes packets errors dropped carrier collsns
> 0 0 0 0 0 0
> vf 0 link/ether 4a:b7:3d:37:f7:56 brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state auto, trust off
> RX: bytes packets mcast bcast dropped
> 0 0 0 0 0
> TX: bytes packets dropped
> 0 0 2
>
> Fixes: dc645daef9af5bcbd9c ("i40e: implement VF stats NDO")
> Signed-off-by: Dennis Chen <dechen@redhat.com>
> Link: https://www.intel.com/content/www/us/en/content-details/596333/intel-ethernet-controller-x710-tm4-at2-carlsville-datasheet.html
> ---
> drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
> index 88e6bef69342..2dbe38eb9494 100644
> --- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
> +++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
> @@ -5006,7 +5006,7 @@ int i40e_get_vf_stats(struct net_device *netdev, int vf_id,
> vf_stats->broadcast = stats->rx_broadcast;
> vf_stats->multicast = stats->rx_multicast;
> vf_stats->rx_dropped = stats->rx_discards + stats->rx_discards_other;
> - vf_stats->tx_dropped = stats->tx_discards;
> + vf_stats->tx_dropped = stats->tx_errors;
>
> return 0;
> }
> --
> 2.49.0
>
Hello,
Any update here?
Dennis Chen
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH net] i40e: report VF tx_dropped with tx_errors instead of tx_discards
2025-07-17 16:46 ` Dennis Chen
@ 2025-07-17 20:05 ` Tony Nguyen
2025-07-21 9:41 ` [Intel-wired-lan] " Romanowski, Rafal
0 siblings, 1 reply; 6+ messages in thread
From: Tony Nguyen @ 2025-07-17 20:05 UTC (permalink / raw)
To: Dennis Chen, netdev
Cc: przemyslaw.kitszel, andrew+netdev, davem, edumazet, kuba, pabeni,
intel-wired-lan
On 7/17/2025 9:46 AM, Dennis Chen wrote:
> On Wed, Jun 18, 2025 at 3:52 PM Dennis Chen <dechen@redhat.com> wrote:
>>
>> Currently the tx_dropped field in VF stats is not updated correctly
>> when reading stats from the PF. This is because it reads from
>> i40e_eth_stats.tx_discards which seems to be unused for per VSI stats,
>> as it is not updated by i40e_update_eth_stats() and the corresponding
>> register, GLV_TDPC, is not implemented[1].
>>
>> Use i40e_eth_stats.tx_errors instead, which is actually updated by
>> i40e_update_eth_stats() by reading from GLV_TEPC.
>>
>> To test, create a VF and try to send bad packets through it:
>>
>> $ echo 1 > /sys/class/net/enp2s0f0/device/sriov_numvfs
>> $ cat test.py
>> from scapy.all import *
>>
>> vlan_pkt = Ether(dst="ff:ff:ff:ff:ff:ff") / Dot1Q(vlan=999) / IP(dst="192.168.0.1") / ICMP()
>> ttl_pkt = IP(dst="8.8.8.8", ttl=0) / ICMP()
>>
>> print("Send packet with bad VLAN tag")
>> sendp(vlan_pkt, iface="enp2s0f0v0")
>> print("Send packet with TTL=0")
>> sendp(ttl_pkt, iface="enp2s0f0v0")
>> $ ip -s link show dev enp2s0f0
>> 16: enp2s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
>> link/ether 3c:ec:ef:b7:e0:ac brd ff:ff:ff:ff:ff:ff
>> RX: bytes packets errors dropped missed mcast
>> 0 0 0 0 0 0
>> TX: bytes packets errors dropped carrier collsns
>> 0 0 0 0 0 0
>> vf 0 link/ether e2:c6:fd:c1:1e:92 brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state auto, trust off
>> RX: bytes packets mcast bcast dropped
>> 0 0 0 0 0
>> TX: bytes packets dropped
>> 0 0 0
>> $ python test.py
>> Send packet with bad VLAN tag
>> .
>> Sent 1 packets.
>> Send packet with TTL=0
>> .
>> Sent 1 packets.
>> $ ip -s link show dev enp2s0f0
>> 16: enp2s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
>> link/ether 3c:ec:ef:b7:e0:ac brd ff:ff:ff:ff:ff:ff
>> RX: bytes packets errors dropped missed mcast
>> 0 0 0 0 0 0
>> TX: bytes packets errors dropped carrier collsns
>> 0 0 0 0 0 0
>> vf 0 link/ether e2:c6:fd:c1:1e:92 brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state auto, trust off
>> RX: bytes packets mcast bcast dropped
>> 0 0 0 0 0
>> TX: bytes packets dropped
>> 0 0 0
>>
>> A packet with non-existent VLAN tag and a packet with TTL = 0 are sent,
>> but tx_dropped is not incremented.
>>
>> After patch:
>>
>> $ ip -s link show dev enp2s0f0
>> 19: enp2s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
>> link/ether 3c:ec:ef:b7:e0:ac brd ff:ff:ff:ff:ff:ff
>> RX: bytes packets errors dropped missed mcast
>> 0 0 0 0 0 0
>> TX: bytes packets errors dropped carrier collsns
>> 0 0 0 0 0 0
>> vf 0 link/ether 4a:b7:3d:37:f7:56 brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state auto, trust off
>> RX: bytes packets mcast bcast dropped
>> 0 0 0 0 0
>> TX: bytes packets dropped
>> 0 0 2
>>
>> Fixes: dc645daef9af5bcbd9c ("i40e: implement VF stats NDO")
>> Signed-off-by: Dennis Chen <dechen@redhat.com>
>> Link: https://www.intel.com/content/www/us/en/content-details/596333/intel-ethernet-controller-x710-tm4-at2-carlsville-datasheet.html
>> ---
>> drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
>> index 88e6bef69342..2dbe38eb9494 100644
>> --- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
>> +++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
>> @@ -5006,7 +5006,7 @@ int i40e_get_vf_stats(struct net_device *netdev, int vf_id,
>> vf_stats->broadcast = stats->rx_broadcast;
>> vf_stats->multicast = stats->rx_multicast;
>> vf_stats->rx_dropped = stats->rx_discards + stats->rx_discards_other;
>> - vf_stats->tx_dropped = stats->tx_discards;
>> + vf_stats->tx_dropped = stats->tx_errors;
>>
>> return 0;
>> }
>> --
>> 2.49.0
>>
> Hello,
>
> Any update here?
Hi Dennis,
Let me check with our validation team and get their status on this.
Thanks,
Tony
^ permalink raw reply [flat|nested] 6+ messages in thread
* RE: [Intel-wired-lan] [PATCH net] i40e: report VF tx_dropped with tx_errors instead of tx_discards
2025-07-17 20:05 ` Tony Nguyen
@ 2025-07-21 9:41 ` Romanowski, Rafal
0 siblings, 0 replies; 6+ messages in thread
From: Romanowski, Rafal @ 2025-07-21 9:41 UTC (permalink / raw)
To: Nguyen, Anthony L, Dennis Chen, netdev@vger.kernel.org
Cc: Kitszel, Przemyslaw, andrew+netdev@lunn.ch, davem@davemloft.net,
edumazet@google.com, kuba@kernel.org, pabeni@redhat.com,
intel-wired-lan@lists.osuosl.org
> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of Tony
> Nguyen
> Sent: Thursday, July 17, 2025 10:06 PM
> To: Dennis Chen <dechen@redhat.com>; netdev@vger.kernel.org
> Cc: Kitszel, Przemyslaw <przemyslaw.kitszel@intel.com>;
> andrew+netdev@lunn.ch; davem@davemloft.net; edumazet@google.com;
> kuba@kernel.org; pabeni@redhat.com; intel-wired-lan@lists.osuosl.org
> Subject: Re: [Intel-wired-lan] [PATCH net] i40e: report VF tx_dropped with
> tx_errors instead of tx_discards
>
>
>
> On 7/17/2025 9:46 AM, Dennis Chen wrote:
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
^ permalink raw reply [flat|nested] 6+ messages in thread
* RE: [Intel-wired-lan] [PATCH net] i40e: report VF tx_dropped with tx_errors instead of tx_discards
2025-06-30 16:49 ` Simon Horman
@ 2025-07-21 9:46 ` Romanowski, Rafal
0 siblings, 0 replies; 6+ messages in thread
From: Romanowski, Rafal @ 2025-07-21 9:46 UTC (permalink / raw)
To: Simon Horman, Dennis Chen, davem@davemloft.net,
edumazet@google.com, kuba@kernel.org, pabeni@redhat.com,
intel-wired-lan@lists.osuosl.org
Cc: netdev@vger.kernel.org, Nguyen, Anthony L, Kitszel, Przemyslaw,
andrew+netdev@lunn.ch
> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of Simon
> Horman
> Sent: Monday, June 30, 2025 6:50 PM
> To: Dennis Chen <dechen@redhat.com>
> Cc: netdev@vger.kernel.org; Nguyen, Anthony L <anthony.l.nguyen@intel.com>;
> Kitszel, Przemyslaw <przemyslaw.kitszel@intel.com>; andrew+netdev@lunn.ch;
> davem@davemloft.net; edumazet@google.com; kuba@kernel.org;
> pabeni@redhat.com; intel-wired-lan@lists.osuosl.org
> Subject: Re: [Intel-wired-lan] [PATCH net] i40e: report VF tx_dropped with
> tx_errors instead of tx_discards
>
> On Wed, Jun 18, 2025 at 03:52:40PM -0400, Dennis Chen wrote:
> > Currently the tx_dropped field in VF stats is not updated correctly
> > when reading stats from the PF. This is because it reads from
> > i40e_eth_stats.tx_discards which seems to be unused for per VSI stats,
> > as it is not updated by i40e_update_eth_stats() and the corresponding
> > register, GLV_TDPC, is not implemented[1].
> >
> > Use i40e_eth_stats.tx_errors instead, which is actually updated by
> > i40e_update_eth_stats() by reading from GLV_TEPC.
>
> ...
>
> > Fixes: dc645daef9af5bcbd9c ("i40e: implement VF stats NDO")
> > Signed-off-by: Dennis Chen <dechen@redhat.com>
> > Link:
> > https://www.intel.com/content/www/us/en/content-details/596333/intel-e
> > thernet-controller-x710-tm4-at2-carlsville-datasheet.html
>
> Hi Dennis,
>
> Thanks for the detailed explanation, it's very much appreciated.
>
> One minor nit, is that there are some leading spaces before "Link: "
> a few lines above. But I suspect you don't need to repost just to address that.
>
> Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2025-07-21 9:46 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2025-06-18 19:52 [PATCH net] i40e: report VF tx_dropped with tx_errors instead of tx_discards Dennis Chen
2025-06-30 16:49 ` Simon Horman
2025-07-21 9:46 ` [Intel-wired-lan] " Romanowski, Rafal
2025-07-17 16:46 ` Dennis Chen
2025-07-17 20:05 ` Tony Nguyen
2025-07-21 9:41 ` [Intel-wired-lan] " Romanowski, Rafal
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