Re: [PATCH 00/11] crypto: ccree - fixes and cleanups

From: Geert Uytterhoeven
Date: Thu Jan 23 2020 - 15:09:08 EST


Hi Gilad,

On Thu, Jan 23, 2020 at 7:19 PM Gilad Ben-Yossef <gilad@xxxxxxxxxxxxx> wrote:
> On Thu, Jan 23, 2020 at 5:46 PM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
> > On Thu, Jan 23, 2020 at 12:44 PM Gilad Ben-Yossef <gilad@xxxxxxxxxxxxx> wrote:
> > > On Wed, Jan 22, 2020 at 6:51 PM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
> > > > On Thu, Jan 16, 2020 at 11:25 AM Gilad Ben-Yossef <gilad@xxxxxxxxxxxxx> wrote:
> > > > > A bunch of fixes and code cleanups for the ccree driver
> > > >
> > > > Thank you!
> > > >
> > > > I wanted to give this a try, but it looks like CCREE is no longer working
> > > > on R-Car H3, both with/without this series.
> > > >
> > > > E.g. with renesas-devel[*] and renesas_defconfig +
> > > > CONFIG_CRYPTO_MANAGER_DISABLE_TESTS=n, I get the following crash:
> > >
> > > Thank you for the bug report Geert!
> > >
> > > My R-Car board is on loan at the moment to another project. I didn't
> > > see this on our internal test board.
> > > I will track down my R-Car board and reproduce this - hopefully
> > > beginning of next week and will get back to you.
> >
> > In the mean time, I've bisected this failure to commit cdfee5623290bc89
> > ("driver core: initialize a default DMA mask for platform device").
> > However, this looks like a red herring, and seems to be only an exposer
> > of an underlying problem.
>
> Thank you for continue digging into this.
>
> > What's happening is that cc_map_aead_request() receives a request with
> > cryptlen = 0. Due to DRV_CRYPTO_DIRECTION_ENCRYPT, the length to map is
> > increased by 8. This seems to works fine if there is sufficient space
> > in the request's scatterlist. However, if the scatterlist has only a
> > single entry of size zero, cc_map_sg() tries to map a zero-length DMA
> > buffer, and the BUG)() is triggered.
> >
>
> OK, this does rings a bell - can you verify please if
> CONFIG_CRYPTO_MANAGER_EXTRA_TESTS is enabled and if it does can you
> see if it happens if it is turned off?

No, I didn't have that option enabled.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds