[dpdk-users] [VMXNET3] vmxnet3_dev_stats_get() segfault when called by pktgen

[longtb5 at viettel.com.vn]

>----- Original Message -----
>From: "keith wiles" <keith.wiles at intel.com>
>To: "Stephen Hemminger" <stephen at networkplumber.org>
>Cc: longtb5 at viettel.com.vn, users at dpdk.org
>Sent: Thursday, September 7, 2017 11:49:39 PM
>Subject: Re: [dpdk-users] [VMXNET3] vmxnet3_dev_stats_get() segfault when called by pktgen
>
>
>I use the option EXTRA_CFLAGS on the command line to improve debug.
>
>make install T=x86_64-native-linuxapp-gcc EXTRA_CFLAGS=“-g -O0”
>
>Using -O0 for gdb is good for non-performance testing.
>
>
>Regards,
>Keith

Hi,

Thanks Keith and Stephen for the pointer. I have enabled the debug flags and acquired some more infos.

(gdb) r
Thread 1 "pktgen" received signal SIGSEGV, Segmentation fault.
0x000000000075aa6c in vmxnet3_hw_tx_stats_get (hw=0x7fffb55b61c0, q=0, res=0x7fffffffdf10) at /home/tester/dpdk/drivers/net/vmxnet3/vmxnet3_ethdev.c:905
905		VMXNET3_UPDATE_TX_STAT(hw, q, ucastPktsTxOK, res);
(gdb) backtrace
#0  0x000000000075aa6c in vmxnet3_hw_tx_stats_get (hw=0x7fffb55b61c0, q=0, res=0x7fffffffdf10) at /home/tester/dpdk/drivers/net/vmxnet3/vmxnet3_ethdev.c:905
#1  0x000000000075b3c8 in vmxnet3_dev_stats_get (dev=0xba34c0 <rte_eth_devices>, stats=0x7fffffffe000) at /home/tester/dpdk/drivers/net/vmxnet3/vmxnet3_ethdev.c:1049
#2  0x00000000004a2f76 in rte_eth_stats_get (port_id=0 '\000', stats=0x7fffffffe000) at /home/tester/dpdk/lib/librte_ether/rte_ethdev.c:1340
#3  0x0000000000467059 in pktgen_process_stats (tim=<optimized out>, arg=<optimized out>) at /home/tester/pktgen-dpdk/app/pktgen-stats.c:468
#4  0x000000000048568a in rte_timer_manage () at /home/tester/dpdk/lib/librte_timer/rte_timer.c:593
#5  0x00000000007b47dd in cli_start ()
#6  0x000000000044891b in pktgen_cli_start () at /home/tester/pktgen-dpdk/app/cli-functions.c:1434
#7  0x00000000004423f6 in main (argc=<optimized out>, argv=<optimized out>) at /home/tester/pktgen-dpdk/app/pktgen-main.c:470
(gdb) l
900	{
901	#define VMXNET3_UPDATE_TX_STAT(h, i, f, r)		\
902			((r)->f = (h)->tqd_start[(i)].stats.f +	\
903				(h)->saved_tx_stats[(i)].f)
904	
905		VMXNET3_UPDATE_TX_STAT(hw, q, ucastPktsTxOK, res);
906		VMXNET3_UPDATE_TX_STAT(hw, q, mcastPktsTxOK, res);
907		VMXNET3_UPDATE_TX_STAT(hw, q, bcastPktsTxOK, res);
908		VMXNET3_UPDATE_TX_STAT(hw, q, ucastBytesTxOK, res);
909		VMXNET3_UPDATE_TX_STAT(hw, q, mcastBytesTxOK, res);
(gdb) p hw->tqd_start
$1 = (Vmxnet3_TxQueueDesc *) 0x0

The problem was on line 902.
This tqd_start is the "start address of all tx queue desc" according to comments in source code. Looks like it was not initialized properly.
I don't have enough knowledge to fix this. Any advice?

Regards,
BL.