On 26/05/2016 11:55, Dmitry Poletaev wrote: > kvm_mmu_page_fault goes to nonpaging_page_fault, which don't find page in > cache and calls nonpaging_map. nonpaging_map exits after critical section > before out_unlock label. For me reaction is normal and looks the same on both > platforms, but I think problem may be here deeper. > After #PF handling kvm enters to guest again and here difference begins. Real > machine have new #PF far away from this address, but qemu falls to kvm again > with #PF on 0xfe05b. > This situation repeats infinitely. Qemu vmcs fields after exit to kvm don't > have important differencies (on my view) with Intel vmcs. > Some more info I received after logging qemu's address translation. > Qemu rises first #PF on first entry to guest (pml4e = 0x3d9fe001 pdpe > = 0x0). On second entry to guest, after kvm handling, it rise #PF again > (pml4e = 0x3d9fe021 pdpe = 0x3d9fa027 pde = 0x0). Next entries to guest > is the same (PF and pml4e = 0x3d9fe021 pdpe = 0x3d9fa027 pde = 0x0).
I think the PDE and PTE should have become non-zero, but I'm not sure. You can use the kvm_flightrecorder script (scripts/kvm/kvm_flightrecorder in the QEMU git tree) to find where the differences start exactly. You can also compare QEMU and Bochs. BTW, have you tried running the VMX testcases from kvm-unit-tests.git? Thanks, Paolo > May be someone know, why it is happens and how I can fix my vmx realization, > or where I should look.
