On 10.07.2025 19:08, Steven Rostedt wrote:
On Thu, 10 Jul 2025 17:41:36 +0200
Jens Remus [off-list ref] wrote:
quoted
cfa + frame->ra_off could be aligned by chance. So could
cfa + frame->fp_off be as well of course.
On s390 the CFA must be aligned (as the SP must be aligned) and the
FP and RA offsets from CFA must be aligned, as pointer / 64-bit integers
(such as 64-bit register values) must be aligned as well.
So the CFA (and/or offset), FP offset, and RA offset could be validated
individually. Not sure if that would be over engineering though.
I wonder if we should just validate that cfa is aligned? Would that work?
I would think that ra_off and fp_off should be aligned as well and if
cfa is aligned then it would still be aligned when adding those offsets.
Makes sense, if the base assumption is that the SFrame information is
valid and the primary intend is to check that the used CFA base register
(i.e. SP or FP) was aligned.
Regards,
Jens
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Jens Remus
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