Re: [PATCH RFC 0/7] powerpc: Beef up single-stepping/instruction emulation infrastructure

[Michael Ellerman]

Michael Neuling  writes:

> Paulus, 
>
>> This patch series extends the code in arch/powerpc/lib/sstep.c so that
>> it handles almost all load and store instructions -- all except the
>> atomic memory operations (lwat, stwat, etc.).  It also makes sure that
>> we use the largest possible aligned accesses to access memory and that
>> we don't access the CPU FP/VMX/VSX registers when they don't contain
>> user data.
>
> Do you have any test cases we can put in selftests for this?

We have lots of plans for them, but no code yet.

cheers

Re: [PATCH RFC 0/7] powerpc: Beef up single-stepping/instruction emulation infrastructure

[Michael Neuling]

Paulus, 

> This patch series extends the code in arch/powerpc/lib/sstep.c so that
> it handles almost all load and store instructions -- all except the
> atomic memory operations (lwat, stwat, etc.).  It also makes sure that
> we use the largest possible aligned accesses to access memory and that
> we don't access the CPU FP/VMX/VSX registers when they don't contain
> user data.

Do you have any test cases we can put in selftests for this?

> With this, it should be possible to replace the body of the alignment
> interrupt handler with a call to emulate_step() or something quite
> similar.

Exercise for the reader? :-)

Mikey

[PATCH RFC 0/7] powerpc: Beef up single-stepping/instruction emulation infrastructure

[Paul Mackerras]

This patch series extends the code in arch/powerpc/lib/sstep.c so that
it handles almost all load and store instructions -- all except the
atomic memory operations (lwat, stwat, etc.).  It also makes sure that
we use the largest possible aligned accesses to access memory and that
we don't access the CPU FP/VMX/VSX registers when they don't contain
user data.

With this, it should be possible to replace the body of the alignment
interrupt handler with a call to emulate_step() or something quite
similar.

Paul.

 arch/powerpc/include/asm/sstep.h |   73 +-
 arch/powerpc/lib/Makefile|2 +-
 arch/powerpc/lib/ldstfp.S|  305 ++-
 arch/powerpc/lib/quad.S  |   62 ++
 arch/powerpc/lib/sstep.c | 1773 +-
 5 files changed, 1564 insertions(+), 651 deletions(-)