Re: WARNING: CPU: 1 PID: 83 at arch/x86/kernel/cpu/sgx/main.c:446 ksgxd+0x1b7/0x1d0

[Jarkko Sakkinen <jarkko@kernel.org>]

On Wed, Aug 24, 2022 at 12:33:07AM +0200, Paul Menzel wrote:
> Dear Dave,
> 
> 
> Thank you for your reply.
> 
> Am 23.08.22 um 18:32 schrieb Dave Hansen:
> > On 8/23/22 06:48, Paul Menzel wrote:
> > > > > I'm suspecting either a BIOS problem.  Reinette (cc'd) also thought this
> > > > > might be a case of the SGX initialization getting a bit too far along
> > > > > when it should have been disabled.
> > > > > 
> > > > > We had some bugs where we didn't stop fast enough after spitting out the
> > > > > "SGX Launch Control is locked..." errors.
> > > 
> > > Let’s hope it’s something known to you.
> > 
> > Thanks for the extra debug info.  Unfortunately, nothing is really
> > sticking out as an obvious problem.
> > 
> > The EREMOVE return codes would be interesting to know, as well as an
> > idea what the physical addresses are that fail and the _counts_ of how
> > many pages get sanitized versus fail.
> 
> Is there a knob to print out this information? Or way to get this
> information using ftrace? I’d like to avoid rebuilding the Linux kernel.

Since __sgx_sanitize_pages() is a local symbol, it's not possible
to attach kprobe into it, so we actually do require a code change
to see inside.

BR, Jarkko