[PATCH v3 4/4] x86: Pass memory range via E820 for kdump

[Dave Young]

> [..]
> 
> I tested on a prototype system with 231 entries in the map with good results.
> Everything succeeds when using kexec to initiate a fast reboot. For crash, it
> works with and without --pass-memmap-cmdline when using noefi. I hit the
> following panic when initiating a crash leaving EFI enabled in the crash kernel:
> 
>  ? __unmap_pmd_range+0x77/0x190
>  unmap_pmd_range+0xcf/0x1c0
>  populate_pgd+0x16d/0x250
>  __cpa_process_fault+0x15/0xb0
>  __change_page_attr+0x15e/0x2a0
>  __change_page_attr_set_clr+0x59/0xc0
>  kernel_map_pages_in_pgd+0x7a/0xb0
>  __map_region+0x46/0x64
>  ? early_idt_handlers+0x117/0x120
>  efi_map_region_fixed+0xd/0xf
>  efi_enter_virtual_mode+0x4c/0x476
>  ? early_idt_handlers+0x117/0x120
>  ? early_idt_handlers+0x117/0x120
>  start_kernel+0x2e5/0x376
>  ? repair_env_string+0x5b/0x5b
>  ? memblock_reserve+0x49/0x4e
>  x86_64_start_reservations+0x2a/0x2c
>  x86_64_start_kernel+0x19f/0x1ae
> 
> However, I was able to reproduce this panic using an earlier version of
> kexec-tools, so I believe it is unrelated to this patch.

Can you test with matt's tree to see if it works?
If it still happens please post the full log.

Thanks
Dave