Re: [PATCH 0/4] [rs6000] ROP support

[Bill Schmidt <wschmidt@linux.ibm.com>]

Hi!  I'd like to ping this series.  It has slightly higher priority from 
my perspective, since I'd like this to be backported in time for GCC 11.2.

Thanks!
Bill

On 4/25/21 8:50 PM, Bill Schmidt via Gcc-patches wrote:
> Add POWER10 support for hashst[p] and hashchk[p] operations.  When
> the -mrop-protect option is selected, any function that loads the link
> register from memory before returning must have protection in the
> prologue and epilogue to ensure the link register save location has
> not been compromised.  If -mprivileged is also specified, the
> protection instructions generated require supervisor privilege.
>
> The patches are broken up into logical chunks:
>   - Option handling
>   - Instruction generation
>   - Predefined macro handling
>   - Test cases
>
> Bootstrapped and tested on a POWER10 system with no regressions.
> Tests on a kernel that enables user-space ROP mitigation were
> successful.  Is this series ok for trunk?  I would also like to later
> backport these patches to GCC for the 11.2 release.
>
> Thanks!
> Bill
>
> Bill Schmidt (4):
>    rs6000: Add -mrop-protect and -mprivileged flags
>    rs6000: Emit ROP-protect instructions in prologue and epilogue
>    rs6000: Conditionally define __ROP_PROTECT__
>    rs6000: Add ROP tests
>
>   gcc/config/rs6000/rs6000-c.c             |  3 +
>   gcc/config/rs6000/rs6000-internal.h      |  2 +
>   gcc/config/rs6000/rs6000-logue.c         | 86 +++++++++++++++++++++---
>   gcc/config/rs6000/rs6000.c               |  7 ++
>   gcc/config/rs6000/rs6000.md              | 39 +++++++++++
>   gcc/config/rs6000/rs6000.opt             |  6 ++
>   gcc/doc/invoke.texi                      | 19 +++++-
>   gcc/testsuite/gcc.target/powerpc/rop-1.c | 16 +++++
>   gcc/testsuite/gcc.target/powerpc/rop-2.c | 16 +++++
>   gcc/testsuite/gcc.target/powerpc/rop-3.c | 19 ++++++
>   gcc/testsuite/gcc.target/powerpc/rop-4.c | 14 ++++
>   gcc/testsuite/gcc.target/powerpc/rop-5.c | 17 +++++
>   12 files changed, 231 insertions(+), 13 deletions(-)
>   create mode 100644 gcc/testsuite/gcc.target/powerpc/rop-1.c
>   create mode 100644 gcc/testsuite/gcc.target/powerpc/rop-2.c
>   create mode 100644 gcc/testsuite/gcc.target/powerpc/rop-3.c
>   create mode 100644 gcc/testsuite/gcc.target/powerpc/rop-4.c
>   create mode 100644 gcc/testsuite/gcc.target/powerpc/rop-5.c
>