[CRIU] [PATCH 2/6] parasite-syscall: generalize the CPU register retrieval and set routines

[Cyrill Gorcunov]

On Tue, Oct 08, 2013 at 11:45:34AM +0400, Alexander Kartashov wrote:
> This patch introduces the routines ptrace_get_gpregs() and ptrace_set_gpregs()
> that wrap the ptrace interface to get and set CPU registers respectively.
> The motivation is to make architecture-independent CRIU code be compatible
> with architectures that don't support the PTRACE_GETREGS and PTRACE_SETREGS
> ptrace calls. Such an architecture provides a generalized notinon of
> a register set that is accessible by PTRACE_GETREGSET and PTRACE_SETREGSET
> ptrace calls.
> 
> Architecture specific implementation is chosen by the macro ARCH_NEED_PTRACE_REGSET
> that is defined for an architecture that support register sets and
> doesn't support the legacy interface.
> 
> Note that ARM supports both interfaces, x86 supports the legacy version
> only and AArch64 doesn't support it that makes it impossible to use
> a single implementation everywhere.

What you mean by "legacy version only" on x86?