makedumpfile: Issue with aarch64 support

[Pratyush Anand]

Hi Atsushi,

* I am adding aarch64 support in makedumpfile. Preliminary patch is here 
[1]. I am having some issue with the dumpdisk created by makedumpfile. 
See, if you get any clue with following inputs.

* I used cp option in kdump.conf to have a good elf vmcore in 
/var/crash/..../vmcore.

* If I run crash over this elf vmcore, then everything goes fine.

* Now I use makedumpfile [1] for dumpdisk creation

  and compression just goes fine.
  # makedumpfile -l --message-level 1 -d 31 /var/crash/..../vmcore vmcore
  Copying data                       : [100.0 %] |

  But, crash does not like the vmcore
  # crash /lib/modules/.../build/vmlinux vmcore -d 31

<readmem: fffffe01ffde2000, KVADDR, "memory section", 32, (FOE),
a2c4eb0>
<read_diskdump: addr: fffffe01ffde2000 paddr: 41fffe2000 cnt: 32>
read_diskdump: SEEK_ERROR: paddr/pfn: 41fffe2000/41fffe max_mapnr:
414000
crash: seek error: kernel virtual address: fffffe01ffde2000  type:
"memory section"

* I tried by removing -d option in makedumpfile , still same issue.

* A print for vaddr in vaddr_to_paddr_arm64 does not show address
fffffe01ffde2000 being asked for translation by makedumpfile core. 
Infact all the vaddr printed are in the range of directly mapped kernel 
VAs, so I did not consider to add support for other memory section like 
vmalloc, vmemmap etc at this point.

Thanks in advance for your help.

~Pratyush

[1] 
https://github.com/pratyushanand/makedumpfile/commit/073bc204c3422d6cee72eed89edb47281ead1a2e