[PATCH net-next 5/5] crypto: pcbc - Remove support for PCBC mode

[Geert Uytterhoeven]

On Tue, 28 Apr 2026 at 04:49, Eric Biggers <ebiggers at kernel.org> wrote:
> The only user of PCBC mode (Propagating Cipher Block Chaining mode) was
> net/rxrpc/rxkad.c, which now uses local code instead.
>
> While PCBC was an interesting cryptographic experiment, it has largely
> been relegated to the history books and academic exercises.  It is
> non-parallelizable (i.e., very slow) and doesn't actually achieve the
> integrity properties it was apparently intended to achieve.
>
> Remove support for it from the crypto API.
>
> Signed-off-by: Eric Biggers <ebiggers at kernel.org>

>  arch/m68k/configs/amiga_defconfig             |   1 -
>  arch/m68k/configs/apollo_defconfig            |   1 -
>  arch/m68k/configs/atari_defconfig             |   1 -
>  arch/m68k/configs/bvme6000_defconfig          |   1 -
>  arch/m68k/configs/hp300_defconfig             |   1 -
>  arch/m68k/configs/mac_defconfig               |   1 -
>  arch/m68k/configs/multi_defconfig             |   1 -
>  arch/m68k/configs/mvme147_defconfig           |   1 -
>  arch/m68k/configs/mvme16x_defconfig           |   1 -
>  arch/m68k/configs/q40_defconfig               |   1 -
>  arch/m68k/configs/sun3_defconfig              |   1 -
>  arch/m68k/configs/sun3x_defconfig             |   1 -

Acked-by: Geert Uytterhoeven <geert at linux-m68k.org> # m68k

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

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