----- Original Message ----- > On 11/09/16 at 11:58am, Wen Congyang wrote: > > On 11/09/2016 11:17 AM, Dave Young wrote: > > > Drop qiaonuohan, seems the mail address is wrong.. > > > > > > On 11/09/16 at 11:01am, Dave Young wrote: > > >> Hi, > > >> > > >> Latest linux kernel enabled kaslr to randomiz phys/virt memory > > >> addresses, we had some effort to support kexec/kdump so that crash > > >> utility can still works in case crashed kernel has kaslr enabled. > > >> > > >> But according to Dave Anderson virsh dump does not work, quoted messages > > >> from Dave below: > > >> > > >> """ > > >> with virsh dump, there's no way of even knowing that KASLR > > >> has randomized the kernel __START_KERNEL_map region, because there is no > > >> virtual address information -- e.g., like "SYMBOL(_stext)" in the kdump > > >> vmcoreinfo data to compare against the vmlinux file symbol value. > > >> Unless virsh dump can export some basic virtual memory data, which > > >> they say it can't, I don't see how KASLR can ever be supported. > > >> """ > > >> > > >> I assume virsh dump is using qemu guest memory dump facility so it > > >> should be first addressed in qemu. Thus post this query to qemu devel > > >> list. If this is not correct please let me know. > > > > IIRC, 'virsh dump --memory-only' uses dump-guest-memory, and 'virsh dump' > > uses migration to dump. > > Do they need different fixes? Dave, I guess you mean --memory-only, but > could you clarify and confirm it?
As I understand it, the "--memory-only" option uses a new "dump-guest-memory" QEMU monitor command that creates an ELF kdump vmcore clone. Dave > > > > > I think I should study kaslr first... > > Thanks for taking care of it. > > > > > Thanks > > Wen Congyang > > > > >> > > >> Could you qemu dump people make it work? Or we can not support virt dump > > >> as long as KASLR being enabled. Latest Fedora kernel has enabled it in > > >> x86_64. > > >> > > >> Thanks > > >> Dave > > > > > > > > > > > > > > > >
