On 03/03/2025 6:53 pm, Andrew Cooper wrote: > Xen currently presents APIC_ESR to guests as a simple read/write register.
This turns out not to be true. I'm trying to finish off the XSA-462 XTF PoC, and my detection for this case wasn't working. It turns out that there was no write path for APIC_ESR ever wired up (i.e. I got my analysis wrong about how vlapic_reg_write() behaved with no APIC_ESR case). Errors could only ever accumulate, and could never be cleared. The behaviour following this patch is correct, but the commit message describing the prior behaviour is not. ~Andrew
