https://bugzilla.kernel.org/show_bug.cgi?id=203845 Sean Christopherson (sean.j.christopherson@xxxxxxxxx) changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |sean.j.christopherson@intel | |.com --- Comment #1 from Sean Christopherson (sean.j.christopherson@xxxxxxxxx) --- The EIP and code stream puts this at the following line in mmu_alloc_direct_roots(): vcpu->arch.mmu->pae_root[i] = root | PT_PRESENT_MASK; The code in question is only encountered on a 32-bit KVM with two-dimensional paging (TDP) is disabled, i.e. without AMD's Nested Page Tables, which fits your setup (i686-pae on Athlon). What I can't figure out is how pae_root would be NULL in this scenario. There is one flow that I think could theoretically result in a NULL pae_root, but it would require using nested virtualization, which doesn't seem to be the case here. I tried to test my theory but running a 32-bit KVM without TDP just hangs for me, i.e. it appears to be broken on Intel VMX at least as far back as v4.20. What was the last kernel that did work on your system? That might help narrow down when things went awry. In the meantime, I'll try to debug/bisect the issue I'm seeing as time allows. -- You are receiving this mail because: You are watching the assignee of the bug.
