[Openswan Users] Netkey + Openswan + OCF && H/W accelerators drivers == kernel crash/panic

[satpal parmar]

On Mon, Oct 17, 2011 at 10:21 AM, David McCullough <
david_mccullough at mcafee.com> wrote:

>
> Jivin satpal parmar lays it down ...
> ...
> >       That's something for the driver writers or the kernel people....
> >
> >
> >
> > I made some progress in my investigation here. It seems there is a bug in
> driver (drivers/crypto/nss-sham.c)
> >
> >
> > static int nss_sham_update_cdma_start(struct nss_sham_dev *dd)
> > {
> >         struct nss_sham_reqctx *ctx = ahash_request_ctx(dd->req);
> >         unsigned int length, final, tail;
> >         struct scatterlist *sg;
> >
> >
> >         if (!ctx->total)
> >                 return 0;
> >
> >
> >         if (ctx->bufcnt || ctx->offset)
> >        return nss_sham_update_cdma_slow(dd); ---------------------->True
> for OCF/cryptodev/crptosoft path.This uses dma_single mapping instead of
> scatterlist.But in case of netkey/IPsec this is not true and we hit case
> >
> >
> >      if (!dma_map_sg(dd->dev, ctx->sg, 1, DMA_TO_DEVICE)) {
> >                 dev_err(dd->dev, "dma_map_sg  error\n");
> >                 return -EINVAL;
> >  which is scatter list DMA implementation and crashes in the end of this
> path (as seen in crash dump). I am yet to explore why we got two different
> paths and why it crashing but I think this is the right direction to
> investigate.
> >
> >
> > @David
> > I know its much to ask but if you can spare some time to see the code and
> confirm it would be great help. You can find code here. <
> http://processors.wiki.ti.com/index.php/Installing_AM389x_C6A816x_DM816x_Crypto_Support
> >
>
> cryptodev will only ever do single block requests (1 entry in the SG list).
> So that might explain the different paths.
>
 Ok!

>
> It seems that for short/unaligned/other border cases that all processing is
> dne by the CPu and not the crypto HW,  so it may be that you are just not
> using the crypt HW ?

In which case?  When I am testing H/W accelerators with cryptotest I can see
visible drop in CPU usage from 97 % to 45 % so I assume H/W accelerator are
working fine with OCF and cryptotest. In Netkey case Its crashing before I
see debug info.

> Maybe if you changed the test with OCF you can still
> get it to fail as well ?
>
Will try this and update you.

>
> Track the code through to where it fails, it might be obvious :-)
>
Yeah! going that way but I am dealing  many sub modules (openswan, ocf,
cryapi, drivers) its hard to concentrate on one plus information on web on
all is a real mess (limited, version problem, stale, incorrect) . Thanks to
you guys I am able to make some progress.

> Have you tried asking the Authors (herman at ti.com), seems they might be
> interested in helping you as well :-)
>
Opened communication channel with TI. But that world is no Opensource. I
know understand  what I mean :)

>
> Cheers,
> David

Thanks again for useful input.
-SP


> --
> David McCullough,      david_mccullough at mcafee.com,  Ph:+61 734352815
> McAfee - SnapGear      http://www.mcafee.com         http://www.uCdot.org
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.openswan.org/pipermail/users/attachments/20111018/ce9c1c98/attachment.html