Re: [x86] 5ac0c41bf3: WARNING: CPU: 0 PID: 0 at arch/x86/mm/extable.c:50 ex_handler_rdmsr_unsafe

[Andy Lutomirski]

On Wed, Jun 15, 2016 at 11:07 AM, Borislav Petkov <bp@xxxxxxxxx> wrote:
> On Wed, Jun 15, 2016 at 10:55:34AM -0700, Andy Lutomirski wrote:
>> Isn't it this one?
>
> Yes, it is.
>
>> I'm not.  If %pF points at some silly helper, we still want the frames below it.
>
> Why silly helper? It points to the rIP where the *MSR instruction is.
> Can't get more precise than that.

A hypothetical helper.

void do_thing(unsigned long msr)
{
  rdmsr(...);
}

void actual_problem(void)
{
  do_thing(0xbaadc0de);
}

I want to see actual_problem in the log.

--Andy