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

Sami Tolvanen
2020-05-15T20:42:55Z

On Fri, May 15, 2020 at 10:28 AM Will Deacon <will@kernel.org> 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:
>
> 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@google.com>
> Cc: Kees Cook <keescook@chromium.org>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Mark Rutland <mark.rutland@am.com>
> Cc: Jann Horn <jannh@google.com>
> Cc: Ard Biesheuvel <ardb@kernel.org>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: <kernel-team@android.com>
>
> --->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