Re: [Crash-utility] question about phys_base

----- Original Message ----- >> >> OK, so then I don't understand what you mean by "may be the same"? >> >> You didn't answer my original question, but if I understand you correctly, >> it would be impossible for the qemu host to create a PT_LOAD segment that >> describes an x86_64 guest's __START_KERNEL_map region, because the host >> doesn't know that what kind of kernel the guest is running. > > Yes. Even if the guest is linux, it is still impossible to do it. Because > the guest maybe in the second kernel. > > qemu-dump walks all guest's page table and collect virtual address and > physical address mapping. If the page is not used by guest, the virtual is set > to 0. I create PT_LOAD according to such mapping. So if the guest is linux, > there may be a PT_LOAD segment that describes __START_KERNEL_map region. > But the information stored in PT_LOAD maybe for the second kernel. If crash > uses it, crash will see the second kernel, not the first kernel. Just to be clear -- what do you mean by the "second" kernel? Do you mean that a guest kernel crashed guest, and did a kdump operation, and that second kdump kernel failed somehow, and now you're trying to do a "virsh dump" on the kdump kernel?

Dave