On Mon, Mar 15, 2010 at 03:39:49PM +0100, Michal Simek wrote: > John Linn wrote: > >> -----Original Message----- > >> From: Michal Simek [mailto:michal.si...@petalogix.com] > >> Sent: Monday, March 15, 2010 2:40 AM > >> To: John Linn > >> Cc: net...@vger.kernel.org; linuxppc-...@ozlabs.org; > > grant.lik...@secretlab.ca; > >> jwbo...@linux.vnet.ibm.com; john.willi...@petalogix.com; John Tyner > >> Subject: Re: [PATCH] [V2] Add non-Virtex5 support for LL TEMAC driver > >> > >> John Linn wrote: > >>> This patch adds support for using the LL TEMAC Ethernet driver on > >>> non-Virtex 5 platforms by adding support for accessing the Soft DMA > >>> registers as if they were memory mapped instead of solely through > > the > >>> DCR's (available on the Virtex 5). > >>> > >>> The patch also updates the driver so that it runs on the MicroBlaze. > >>> The changes were tested on the PowerPC 440, PowerPC 405, and the > >>> MicroBlaze platforms. > >> Which git-tree have you tested on? (Of course microblaze) > > > > It was tested on the Xilinx tree for MicroBlaze which is based on the > > mainline and the Petalogix tree as DMA was needed. I tried to build > > against the mainline head but got errors with the DMA routines. I guess > > it's possible that it was a configuration issue there as I didn't dig > > real deep. > > New dma api is in for-linus branch. > I tested it on that version and I am seeing some weird things. :-( > Access to bad area. I will try your tree. > > The second thing which I see is in ll_temac_recv function. > On the following line is read a packet length which could be 0-16k. > length = cur_p->app4 & 0x3FFF; > > But allocated skb has max size XTE_MAX_JUMBO_FRAME_SIZE + XTE_ALIGN. > > What happen if driver get packet greater than 9kB? > I got it (I don't know how) but skb_put has one checking mechanism which > will cal skb_over_panic which caused panic. > That's why I think that will be good always to check that length is less > than XTE_MAX_JUMBO_FRAME_SIZE + XTE_ALIGN. > > What do you think?
I agree. IIRC the LLTEMAC when configured to accept jumboframes will accepts packets up to 16K and the driver should handle that without raising panics. I remeber beeing a bit surprised about that when hacking the QEMU model. Not sure if I remember correctly though. Cheers _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
