Messages in this thread | ![/](/images/icornerl.gif) | | Date | Mon, 29 Jan 2024 09:07:13 -0800 | From | "H. Peter Anvin" <> | Subject | Re: [RFC] Randomness on confidential computing platforms |
| |
On January 29, 2024 8:41:49 AM PST, "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> wrote: >On Mon, Jan 29, 2024 at 08:30:11AM -0800, Dave Hansen wrote: >> On 1/26/24 05:42, Kirill A. Shutemov wrote: >> > 3. Panic after enough re-tries of RDRAND/RDSEED instructions fail. >> > Another DoS variant against the Guest. >> >> I think Sean was going down the same path, but I really dislike the idea >> of having TDX-specific (or CoCo-specific) policy here. >> >> How about we WARN_ON() RDRAND/RDSEED going bonkers? The paranoid folks >> can turn on panic_on_warn, if they haven't already. > >Sure, we can do it for kernel, but we have no control on what userspace >does. > >Sensible userspace on RDRAND/RDSEED failure should fallback to kernel >asking for random bytes, but who knows if it happens in practice >everywhere. > >Do we care? >
You can't fix what you can't touch.
| ![\](/images/icornerr.gif) |