Re: [PATCH 0/6] Clean up Shadow Call Stack patches for 5.8

[Sami Tolvanen]

On Fri, May 15, 2020 at 10:28 AM Will Deacon <will@xxxxxxxxxx> wrote:
>
> Hi all,
>
> Here's a series of cleanups I hacked together on top of a modified v13
> of the Shadow Call Stack patches from Sami:
>
>   20200515172355.GD23334@willie-the-truck">https://lore.kernel.org/r/20200515172355.GD23334@willie-the-truck
>
> The main changes are:
>
>   * Move code out of arch/arm64 and into the core implementation
>   * Store the full SCS stack pointer instead of the offset
>   * Code simplification and general style things
>
> I'd like to queue this on top early next week so that it can spend some
> quality time in linux-next.
>
> Cheers,
>
> Will
>
> Cc: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
> Cc: Kees Cook <keescook@xxxxxxxxxxxx>
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Mark Rutland <mark.rutland@xxxxxx>
> Cc: Jann Horn <jannh@xxxxxxxxxx>
> Cc: Ard Biesheuvel <ardb@xxxxxxxxxx>
> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> Cc: <kernel-team@xxxxxxxxxxx>
>
> --->8
>
> Will Deacon (6):
>   arm64: scs: Store absolute SCS stack pointer value in thread_info
>   scs: Move accounting into alloc/free functions
>   arm64: scs: Use 'scs_sp' register alias for x18
>   scs: Move scs_overflow_check() out of architecture code
>   scs: Remove references to asm/scs.h from core code
>   scs: Move DEFINE_SCS macro into core code
>
>  arch/Kconfig                         |  4 +--
>  arch/arm64/include/asm/scs.h         | 29 ++++------------
>  arch/arm64/include/asm/thread_info.h |  4 +--
>  arch/arm64/kernel/asm-offsets.c      |  2 +-
>  arch/arm64/kernel/entry.S            | 10 +++---
>  arch/arm64/kernel/head.S             |  2 +-
>  arch/arm64/kernel/process.c          |  2 --
>  arch/arm64/kernel/scs.c              |  6 +---
>  include/linux/scs.h                  | 16 +++++----
>  kernel/sched/core.c                  |  3 ++
>  kernel/scs.c                         | 52 +++++++++++++---------------
>  11 files changed, 55 insertions(+), 75 deletions(-)
>
> --
> 2.26.2.761.g0e0b3e54be-goog

Thanks, Will. I tested these on my SCS tree and didn't run into any
issues. Looks good to me.

Sami