On 26/05/2025 6:59 pm, Manuel Bouyer wrote: > Hello, > since I updated to Xen 4.18.5 (from 4.18.4), NetBSD's dbregs-related tests > are failing. Only for PV; PVH and HVM guests are fine. They are > failing for both 32bits and 64bits guests. > > I tracked it down to dr6 being 0xffff0ff0 after the trace trap, when at > last one of the lower bits should be 1 (I think it's bit 0, from the code). > > I looked at the commit log between 4.18.4 and 4.18.5 but didn't see > anything obvious. > > Any idea ? >
Have you got a link to the test in question? We've had a couple of bugfixes in this area, although debug handling isn't helped by the fact that both the SDM and APM are factually incorrect on how to write a #DB handler (and the vendors are moving at a glacial pace to correct them). ~Andrew
