[RFC PATCH v2 0/2] ARM: VFP: Save / restore VFP state on the signal handler path

[Imre Deak]

This fixes a VFP corruption problem in a process's main thread, when
both the main thread and a signal handler triggered for the process
uses floating point ops.

Changes since v1:
- save / restore VFP exception registers as well, to support user
  space exception handling/VFP emulation.
- extend the existing ptrace VFP struct with the exception regs,
  so that the VFP frame is equivalent for the ptrace and signal
  handler case.

--Imre