Re: [Xen-devel] [PATCH v4 0/9] libxc: support building large pv-domains

[Wei Liu <wei.liu2@xxxxxxxxxx>]

On Thu, Nov 12, 2015 at 06:09:54AM +0100, Juergen Gross wrote:
> On 05/11/15 15:36, Juergen Gross wrote:
> > The Xen hypervisor supports starting a dom0 with large memory (up to
> > the TB range) by not including the initrd and p2m list in the initial
> > kernel mapping. Especially the p2m list can grow larger than the
> > available virtual space in the initial mapping.
> > 
> > The started kernel is indicating the support of each feature via
> > elf notes.
> > 
> > This series enables the domain builder in libxc to do the same as the
> > hypervisor. This enables starting of huge pv-domUs via xl.
> > 
> > Unmapped initrd is supported for 64 and 32 bit domains, omitting the
> > p2m from initial kernel mapping is possible for 64 bit domains only.
> > 
> > Tested with:
> > - 32 bit domU (kernel not supporting unmapped initrd)
> > - 32 bit domU (kernel supporting unmapped initrd)
> > - 1 GB 64 bit domU (kernel supporting unmapped initrd, not p2m)
> > - 1 GB 64 bit domU (kernel supporting unmapped initrd and p2m)
> > - 900GB 64 bit domU (kernel supporting unmapped initrd and p2m)
> > - HVM domU
> > 
> > Changes in v4:
> > - updated patch 1 as suggested by Wei Liu (comment and variable name)
> > - modify comment in patch 6 as suggested by Wei Liu
> > - rework of patch 8 reducing line count by nearly 100
> > - added some additional plausibility checks to patch 8 as suggested by
> >   Wei Liu
> > - renamed round_pg() to round_pg_up() in patch 9 as suggested by Wei Liu
> > 
> > Changes in v3:
> > - Rebased the complete series to new staging (hvm builder patches by
> >   Roger Pau Monne)
> > - Removed old patch 1 as it broke stubdom build
> > - Introduced new Patch 1 to make allocation of guest memory more clear
> >   regarding virtual/physical memory allocation (requested by Ian Campbell)
> > - Change name of flag to indicate support of unmapped initrd in patch 2
> >   (requested by Ian Campbell)
> > - Introduce new patches 3, 4, 5 ("rename domain builder count_pgtables to
> >   alloc_pgtables", "introduce domain builder architecture specific data",
> >   "use domain builder architecture private data for x86 pv domains") to
> >   assist later page table work
> > - don't fiddle with initrd virtual address in patch 6 (was patch 3 in v2),
> >   add explicit initrd parameters for start_info in struct xc_dom_image
> >   instead (requested by Ian Campbell)
> > - Introduce new patch 8 ("rework of domain builder's page table handler")
> >   to be able to use common helpers for unmapped p2m list (requested by
> >   Ian Campbell)
> > - use now known segment size in pages for p2m list in patch 9 (was patch
> >   5 in v2) instead of fiddling with segment end address (requested by
> >   Ian Campbell)
> > - split alloc_p2m_list() in patch 9 (was patch 5 in v2) to 32/64 bit
> >   variants (requested by Ian Campbell)
> > 
> > Changes in v2:
> > - patch 2 has been removed as it has been applied already
> > - introduced new patch 2 as suggested by Ian Campbell: add a flag
> >   indicating support of an unmapped initrd to the parsed elf data of
> >   the elf_dom_parms structure
> > - updated patch description of patch 3 as requested by Ian Campbell
> > 
> > 
> > Juergen Gross (9):
> >   libxc: reorganize domain builder guest memory allocator
> >   xen: add generic flag to elf_dom_parms indicating support of unmapped
> >     initrd
> >   libxc: rename domain builder count_pgtables to alloc_pgtables
> >   libxc: introduce domain builder architecture specific data
> >   libxc: use domain builder architecture private data for x86 pv domains
> >   libxc: create unmapped initrd in domain builder if supported
> >   libxc: split p2m allocation in domain builder from other magic pages
> >   libxc: rework of domain builder's page table handler
> >   libxc: create p2m list outside of kernel mapping if supported
> > 
> >  stubdom/grub/kexec.c               |  12 +-
> >  tools/libxc/include/xc_dom.h       |  34 +--
> >  tools/libxc/xc_dom_arm.c           |   6 +-
> >  tools/libxc/xc_dom_core.c          | 180 ++++++++----
> >  tools/libxc/xc_dom_x86.c           | 563 
> > +++++++++++++++++++++----------------
> >  tools/libxc/xg_private.h           |  39 +--
> >  xen/arch/x86/domain_build.c        |   4 +-
> >  xen/common/libelf/libelf-dominfo.c |   3 +
> >  xen/include/xen/libelf.h           |   1 +
> >  9 files changed, 490 insertions(+), 352 deletions(-)
> 
> Could someone please comment on patches 1, 8 and 9?
> 

It's on my radar. I haven't got to this yet. I will review this series
at some point.

Wei.

> 
> Juergen
> 

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel