Re: [PATCH v2 23/31] arm64: Debugging support

From: Arnd Bergmann
Date: Mon Aug 20 2012 - 16:11:05 EST


On Monday 20 August 2012, Will Deacon wrote:
> On Mon, Aug 20, 2012 at 10:07:54AM +0100, Will Deacon wrote:
> > On Fri, Aug 17, 2012 at 08:06:07AM +0100, Arnd Bergmann wrote:
> > > Sorry for the dumb question, but why do you even need PTRACE_GET_THREAD_AREA
> > > for 64 bit tasks? I thought the thread pointer is a GPR, or is this just
> > > for compat tasks?
> >
> > The TLS is stored in a co-processor register which is read-only for
> > userspace.
>
> I should elaborate: the register is RW for AArch64 tasks, RO for aarch32
> tasks (although that doesn't affect the need for the ptrace request).

So can't you just /add/ that register to the GPR regset?

Arnd
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