Re: [Patch V5 00/16] xen: support pv-domains larger than 512GB

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Fri, Jul 10, 2015 at 02:47:45PM +0200, Juergen Gross wrote:
> Support 64 bit pv-domains with more than 512GB of memory.
> 
> Following test have been done:
> - 64 bit dom0 on 8GB machine
> - 64 bit dom0 on 1TB machine (resolving p2m/E820-map conflict)
> - 32 bit dom0 on 8GB machine
> - 64 bit dom0 on 8GB machine with faked kernel/E820-map conflict
> - 64 bit dom0 on 8GB machine with faked pgtable/E820-map conflict
> - 64 bit dom0 on 8GB machine with faked initrd/E820-map conflict
> - 64 bit dom0 on 8GB machine with faked p2m/E820-map conflict
> - 64 bit domU (sizes up to 900GB)
> - 32 bit domU

Woot!

Thank you for doing that. I noticed that you used the 'normal'
sizes, but nothing as odd as '3145M' or such to try to break
things. Not sure if it is worht it - as the test suite that
Boris runs does run with some odd sizes to catch this.

I only had one comment about the #13 patch, otherwise I think
we are OK with this patchset?

> 
> Changes in V5:
> - support architectures with undefined KERNEL_PAGE_RO in patch 12
> - correct memblock_reserve() area of kernel page tables on 32 bit
> - add some more comments in patch 1
> - some modifications in patch 13 (memblock_reserve for shared_info removed,
>   for xenstore only necessary if not dom0)
> 
> Changes in V4:
> - new patch 13 (add explicit memblock_reserve() calls for special pages)
> 
> Changes in V3:
> - rename xen_chk_e820_reserved() to xen_is_e820_reserved() as requested by
>   David Vrabel
> - add __initdata tag to global variables in patch 10
> - move initrd conflict checking after reserving p2m memory (patch 11)
> 
> Changes in V2:
> - some clarifications and better explanations in commit messages 
> - add header changes of include/xen/interface/xen.h (patch 01)
> - add wmb() when incrementing p2m_generation (patch 02)
> - add new patch 03 (don't build mfn tree if tools don't need it)
> - add new patch 06 (split counting of extra memory pages from remapping)
> - add new patch 07 (check memory area against e820 map)
> - replace early_iounmap() with early_memunmap() (patch 07->patch 08)
> - rework patch 09 (check for kernel memory conflicting with memory layout)
> - rework patch 10 (check pre-allocated page tables for conflict with memory map)
> - combine old patches 08 and 11 into patch 11
> - add new patch 12 (provide early_memremap_ro to establish read-only mapping)
> - rework old patch 12 (if p2m list located in to be remapped region delay
>   remapping) to copy p2m list in case of a conflict (now patch 13)
> - correct Kconfig dependency (patch 13->14)
> - don't limit dom0 to 512GB (patch 13->14)
> - modify parameter parsing to work in very early boot (patch 13->14)
> - add new patch 15 to do some cleanup
> - remove old patch 05 (simplify xen_set_identity_and_remap() by using global
>   variables)
> - remove old patch 08 (detect pre-allocated memory interfering with e820 map)
> 
> 
> Juergen Gross (16):
>   xen: sync with xen headers
>   xen: save linear p2m list address in shared info structure
>   xen: don't build mfn tree if tools don't need it
>   xen: eliminate scalability issues from initial mapping setup
>   xen: move static e820 map to global scope
>   xen: split counting of extra memory pages from remapping
>   xen: check memory area against e820 map
>   xen: find unused contiguous memory area
>   xen: check for kernel memory conflicting with memory layout
>   xen: check pre-allocated page tables for conflict with memory map
>   xen: check for initrd conflicting with e820 map
>   mm: provide early_memremap_ro to establish read-only mapping
>   xen: add explicit memblock_reserve() calls for special pages
>   xen: move p2m list if conflicting with e820 map
>   xen: allow more than 512 GB of RAM for 64 bit pv-domains
>   xen: remove no longer needed p2m.h
> 
>  Documentation/kernel-parameters.txt  |   7 +
>  arch/x86/include/asm/xen/interface.h |  96 +++++++-
>  arch/x86/include/asm/xen/page.h      |   8 +-
>  arch/x86/xen/Kconfig                 |  20 +-
>  arch/x86/xen/enlighten.c             |   4 +-
>  arch/x86/xen/mmu.c                   | 397 ++++++++++++++++++++++++++++++---
>  arch/x86/xen/p2m.c                   |  43 +++-
>  arch/x86/xen/p2m.h                   |  15 --
>  arch/x86/xen/setup.c                 | 414 ++++++++++++++++++++++++++---------
>  arch/x86/xen/xen-head.S              |   2 +
>  arch/x86/xen/xen-ops.h               |   7 +
>  include/asm-generic/early_ioremap.h  |   2 +
>  include/asm-generic/fixmap.h         |   3 +
>  include/xen/interface/xen.h          |  35 +--
>  mm/early_ioremap.c                   |  12 +
>  15 files changed, 867 insertions(+), 198 deletions(-)
>  delete mode 100644 arch/x86/xen/p2m.h
> 
> -- 
> 2.1.4
>