[PATCH 0/4] powerpc: KASAN for 64-bit Book3S on Radix

[Christophe Leroy]

Le 07/08/2019 à 01:38, Daniel Axtens a écrit :
> Building on the work of Christophe, Aneesh and Balbir, I've ported
> KASAN to 64-bit Book3S kernels running on the Radix MMU.
> 
> It builds on top Christophe's work on 32bit. It also builds on my
> generic KASAN_VMALLOC series, available at:
> https://patchwork.kernel.org/project/linux-mm/list/?series=153209

Would be good to send that one to the powerpc list as well.

> 
> This provides full inline instrumentation on radix, but does require
> that you be able to specify the amount of memory on the system at
> compile time. More details in patch 4.
> 
> Notable changes from the RFC:
> 
>   - I've dropped Book3E 64-bit for now.
> 
>   - Now instead of hacking into the KASAN core to disable module
>     allocations, we use KASAN_VMALLOC.
> 
>   - More testing, including on real hardware. This revealed that
>     discontiguous memory is a bit of a headache, at the moment we
>     must disable memory not contiguous from 0.
>     
>   - Update to deal with kasan bitops instrumentation that landed
>     between RFC and now.

This is rather independant and also applies to PPC32. Could it be a 
separate series that Michael could apply earlier ?

Christophe

> 
>   - Documentation!
> 
>   - Various cleanups and tweaks.
> 
> I am getting occasional problems on boot of real hardware where it
> seems vmalloc space mappings don't get installed in time. (We get a
> BUG that memory is not accessible, but by the time we hit xmon the
> memory then is accessible!) It happens once every few boots. I haven't
> yet been able to figure out what is happening and why. I'm going to
> look in to it, but I think the patches are in good enough shape to
> review while I work on it.
> 
> Regards,
> Daniel
> 
> Daniel Axtens (4):
>    kasan: allow arches to provide their own early shadow setup
>    kasan: support instrumented bitops with generic non-atomic bitops
>    powerpc: support KASAN instrumentation of bitops
>    powerpc: Book3S 64-bit "heavyweight" KASAN support
> 
>   Documentation/dev-tools/kasan.rst            |   7 +-
>   Documentation/powerpc/kasan.txt              | 111 ++++++++++++++
>   arch/powerpc/Kconfig                         |   4 +
>   arch/powerpc/Kconfig.debug                   |  21 +++
>   arch/powerpc/Makefile                        |   7 +
>   arch/powerpc/include/asm/bitops.h            |  25 ++--
>   arch/powerpc/include/asm/book3s/64/radix.h   |   5 +
>   arch/powerpc/include/asm/kasan.h             |  35 ++++-
>   arch/powerpc/kernel/process.c                |   8 ++
>   arch/powerpc/kernel/prom.c                   |  57 +++++++-
>   arch/powerpc/mm/kasan/Makefile               |   1 +
>   arch/powerpc/mm/kasan/kasan_init_book3s_64.c |  76 ++++++++++
>   include/asm-generic/bitops-instrumented.h    | 144 ++++++++++---------
>   include/linux/kasan.h                        |   2 +
>   lib/Kconfig.kasan                            |   3 +
>   mm/kasan/init.c                              |  10 ++
>   16 files changed, 431 insertions(+), 85 deletions(-)
>   create mode 100644 Documentation/powerpc/kasan.txt
>   create mode 100644 arch/powerpc/mm/kasan/kasan_init_book3s_64.c
>