* gianfar.c null pointer deref in gfar_start_xmit().
@ 2011-08-03 2:44 Robin Holt
2011-08-09 6:54 ` Robin Holt
0 siblings, 1 reply; 6+ messages in thread
From: Robin Holt @ 2011-08-03 2:44 UTC (permalink / raw)
To: Sandeep Gopalpet, David S. Miller; +Cc: netdev
While using the v3.0 kernel on a Freescale P1010RDB with 3 minor patches
(None which affect gianfar.c), I get a NULL pointer deref at:
static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
...
regs = tx_queue->grp->regs;
I put a BUG_ON(tx_queue->grp) just before this line and it did trip.
I have not looked at this any more than that.
Any suggestions would be welcome. To reproduce, all I need to do is
a few sequences of pings.
Thanks,
Robin
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: gianfar.c null pointer deref in gfar_start_xmit(). 2011-08-03 2:44 gianfar.c null pointer deref in gfar_start_xmit() Robin Holt @ 2011-08-09 6:54 ` Robin Holt 2011-08-09 7:10 ` Eric Dumazet 0 siblings, 1 reply; 6+ messages in thread From: Robin Holt @ 2011-08-09 6:54 UTC (permalink / raw) To: Sandeep Gopalpet, David S. Miller; +Cc: netdev On Tue, Aug 02, 2011 at 09:44:38PM -0500, Robin Holt wrote: > > While using the v3.0 kernel on a Freescale P1010RDB with 3 minor patches > (None which affect gianfar.c), I get a NULL pointer deref at: > > static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev) > { > ... > regs = tx_queue->grp->regs; > > I put a BUG_ON(tx_queue->grp) just before this line and it did trip. > I have not looked at this any more than that. > > Any suggestions would be welcome. To reproduce, all I need to do is > a few sequences of pings. I was able to reproduce this with the net-next-2.6 kernel as well. Robin ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: gianfar.c null pointer deref in gfar_start_xmit(). 2011-08-09 6:54 ` Robin Holt @ 2011-08-09 7:10 ` Eric Dumazet 2011-08-09 13:06 ` Robin Holt 0 siblings, 1 reply; 6+ messages in thread From: Eric Dumazet @ 2011-08-09 7:10 UTC (permalink / raw) To: Robin Holt; +Cc: Sandeep Gopalpet, David S. Miller, netdev Le mardi 09 août 2011 à 01:54 -0500, Robin Holt a écrit : > On Tue, Aug 02, 2011 at 09:44:38PM -0500, Robin Holt wrote: > > > > While using the v3.0 kernel on a Freescale P1010RDB with 3 minor patches > > (None which affect gianfar.c), I get a NULL pointer deref at: > > > > static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev) > > { > > ... > > regs = tx_queue->grp->regs; > > > > I put a BUG_ON(tx_queue->grp) just before this line and it did trip. > > I have not looked at this any more than that. > > > > Any suggestions would be welcome. To reproduce, all I need to do is > > a few sequences of pings. > > I was able to reproduce this with the net-next-2.6 kernel as well. > This driver incorrectly assumes a non dense txqueue array is possible for a netdev, but its not true. In the meantime, you could force it to use one tx_queue only. tx_queues = (u32 *)of_get_property(np, "fsl,num_tx_queues", NULL); num_tx_qs = tx_queues ? *tx_queues : 1; ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: gianfar.c null pointer deref in gfar_start_xmit(). 2011-08-09 7:10 ` Eric Dumazet @ 2011-08-09 13:06 ` Robin Holt 2011-08-10 6:01 ` Eric Dumazet 0 siblings, 1 reply; 6+ messages in thread From: Robin Holt @ 2011-08-09 13:06 UTC (permalink / raw) To: Eric Dumazet; +Cc: Robin Holt, Sandeep Gopalpet, David S. Miller, netdev On Tue, Aug 09, 2011 at 09:10:13AM +0200, Eric Dumazet wrote: > Le mardi 09 août 2011 à 01:54 -0500, Robin Holt a écrit : > > On Tue, Aug 02, 2011 at 09:44:38PM -0500, Robin Holt wrote: > > > > > > While using the v3.0 kernel on a Freescale P1010RDB with 3 minor patches > > > (None which affect gianfar.c), I get a NULL pointer deref at: > > > > > > static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev) > > > { > > > ... > > > regs = tx_queue->grp->regs; > > > > > > I put a BUG_ON(tx_queue->grp) just before this line and it did trip. > > > I have not looked at this any more than that. > > > > > > Any suggestions would be welcome. To reproduce, all I need to do is > > > a few sequences of pings. > > > > I was able to reproduce this with the net-next-2.6 kernel as well. > > > > This driver incorrectly assumes a non dense txqueue array is possible > for a netdev, but its not true. > > In the meantime, you could force it to use one tx_queue only. > > tx_queues = (u32 *)of_get_property(np, "fsl,num_tx_queues", NULL); > num_tx_qs = tx_queues ? *tx_queues : 1; I fixed up the .dts file and now it works. I have not tested the RGMII interface yet so I do not know if that supports multiple queues. I assume I could find it in the documentation. What might I be looking for? Thanks, Robin ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: gianfar.c null pointer deref in gfar_start_xmit(). 2011-08-09 13:06 ` Robin Holt @ 2011-08-10 6:01 ` Eric Dumazet 2011-08-10 9:32 ` Robin Holt 0 siblings, 1 reply; 6+ messages in thread From: Eric Dumazet @ 2011-08-10 6:01 UTC (permalink / raw) To: Robin Holt; +Cc: Sandeep Gopalpet, David S. Miller, netdev Le mardi 09 août 2011 à 08:06 -0500, Robin Holt a écrit : > On Tue, Aug 09, 2011 at 09:10:13AM +0200, Eric Dumazet wrote: > > Le mardi 09 août 2011 à 01:54 -0500, Robin Holt a écrit : > > > On Tue, Aug 02, 2011 at 09:44:38PM -0500, Robin Holt wrote: > > > > > > > > While using the v3.0 kernel on a Freescale P1010RDB with 3 minor patches > > > > (None which affect gianfar.c), I get a NULL pointer deref at: > > > > > > > > static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev) > > > > { > > > > ... > > > > regs = tx_queue->grp->regs; > > > > > > > > I put a BUG_ON(tx_queue->grp) just before this line and it did trip. > > > > I have not looked at this any more than that. > > > > > > > > Any suggestions would be welcome. To reproduce, all I need to do is > > > > a few sequences of pings. > > > > > > I was able to reproduce this with the net-next-2.6 kernel as well. > > > > > > > This driver incorrectly assumes a non dense txqueue array is possible > > for a netdev, but its not true. > > > > In the meantime, you could force it to use one tx_queue only. > > > > tx_queues = (u32 *)of_get_property(np, "fsl,num_tx_queues", NULL); > > num_tx_qs = tx_queues ? *tx_queues : 1; > > I fixed up the .dts file and now it works. I have not tested the RGMII > interface yet so I do not know if that supports multiple queues. I assume > I could find it in the documentation. What might I be looking for? > What exact change did you in dts ? Assuming your p1010rdb is single core powerpc, I fail to see why 8 queues should be enabled on NIC. It only increases number of interrupts if multiple flows are in use, and memory footprint. ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: gianfar.c null pointer deref in gfar_start_xmit(). 2011-08-10 6:01 ` Eric Dumazet @ 2011-08-10 9:32 ` Robin Holt 0 siblings, 0 replies; 6+ messages in thread From: Robin Holt @ 2011-08-10 9:32 UTC (permalink / raw) To: Eric Dumazet; +Cc: Robin Holt, Sandeep Gopalpet, David S. Miller, netdev On Wed, Aug 10, 2011 at 08:01:01AM +0200, Eric Dumazet wrote: > Le mardi 09 août 2011 à 08:06 -0500, Robin Holt a écrit : > > On Tue, Aug 09, 2011 at 09:10:13AM +0200, Eric Dumazet wrote: > > > Le mardi 09 août 2011 à 01:54 -0500, Robin Holt a écrit : > > > > On Tue, Aug 02, 2011 at 09:44:38PM -0500, Robin Holt wrote: > > > > > > > > > > While using the v3.0 kernel on a Freescale P1010RDB with 3 minor patches > > > > > (None which affect gianfar.c), I get a NULL pointer deref at: > > > > > > > > > > static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev) > > > > > { > > > > > ... > > > > > regs = tx_queue->grp->regs; > > > > > > > > > > I put a BUG_ON(tx_queue->grp) just before this line and it did trip. > > > > > I have not looked at this any more than that. > > > > > > > > > > Any suggestions would be welcome. To reproduce, all I need to do is > > > > > a few sequences of pings. > > > > > > > > I was able to reproduce this with the net-next-2.6 kernel as well. > > > > > > > > > > This driver incorrectly assumes a non dense txqueue array is possible > > > for a netdev, but its not true. > > > > > > In the meantime, you could force it to use one tx_queue only. > > > > > > tx_queues = (u32 *)of_get_property(np, "fsl,num_tx_queues", NULL); > > > num_tx_qs = tx_queues ? *tx_queues : 1; > > > > I fixed up the .dts file and now it works. I have not tested the RGMII > > interface yet so I do not know if that supports multiple queues. I assume > > I could find it in the documentation. What might I be looking for? > > > > What exact change did you in dts ? I changed arch/powerpc/boot/dts/p1010si.dtsi and modified all lines that had fsl,num_rx_queues and fsl,num_tx_queues then recompiled and rebuilt my multi-image boot file. It looks like my boot loader might be missing something. The p1010 reference manual has a section 15.7.2 Multigroup Mode Initialization. I assume that sections initialize before using multigroup mode steps are not getting done in the boot loader. Does that possibly sound like the right section of the manual? > > Assuming your p1010rdb is single core powerpc, I fail to see why 8 > queues should be enabled on NIC. It only increases number of interrupts > if multiple flows are in use, and memory footprint. Thanks, Robin ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2011-08-10 9:32 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2011-08-03 2:44 gianfar.c null pointer deref in gfar_start_xmit() Robin Holt 2011-08-09 6:54 ` Robin Holt 2011-08-09 7:10 ` Eric Dumazet 2011-08-09 13:06 ` Robin Holt 2011-08-10 6:01 ` Eric Dumazet 2011-08-10 9:32 ` Robin Holt
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).