Re: [PATCH v11 6/9] x86/cet: Add PTRACE interface for CET

From: Andy Lutomirski
Date: Thu Sep 03 2020 - 12:15:44 EST


On Thu, Sep 3, 2020 at 9:12 AM Dave Hansen <dave.hansen@xxxxxxxxx> wrote:
>
> On 9/3/20 9:09 AM, Yu, Yu-cheng wrote:
> > If the debugger is going to write an MSR, only in the third case would
> > this make a slight sense. For example, if the system has CET enabled,
> > but the task does not have CET enabled, and GDB is writing to a CET MSR.
> > But still, this is strange to me.
>
> If this is strange, then why do we even _implement_ writes?

Well, if gdb wants to force a tracee to return early from a function,
wouldn't it want the ability to modify SSP?

--Andy