[PATCH 1/2] powerpc/64s/syscall: Use pt_regs.trap to distinguish syscall ABI difference between sc and scv syscalls

[Dmitry V. Levin]

On Thu, May 20, 2021 at 09:19:30PM +1000, Nicholas Piggin wrote:
> The sc and scv 0 system calls have different ABI conventions, and
> ptracers need to know which system call type is being used if it wants
> to look at the syscall registers.

typo: s/if it wants/if they want/

> Document that pt_regs.trap can be used for this, and fix one in-tree user
> to work with scv 0 syscalls.
> 
> Fixes: 7fa95f9adaee ("powerpc/64s: system call support for scv/rfscv instructions")
> Reported-by: "Dmitry V. Levin" <ldv at altlinux.org>
> Suggested-by: "Dmitry V. Levin" <ldv at altlinux.org>
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>

Also consider adding
Cc: stable at vger.kernel.org # 5.9+

Besides that, looks good, thanks!


-- 
ldv