Re: [Qemu-devel] [PATCH 0/9 v2] Make monitor command 'dump-guest-memory' dump in kdump-compressed format

[qiaonuohan]

Sorry, the cc list is wrong, I will resend the mails.
> -----Original Message-----
> From: address@hidden [mailto:address@hidden
> Sent: Wednesday, May 08, 2013 9:54 AM
> To: address@hidden
> Cc:
> address@hidden@address@hidden@jp.fujitsu.c
> address@hidden; Qiao Nuohan
> Subject: [PATCH 0/9 v2] Make monitor command 'dump-guest-memory' dump in
> kdump-compressed format
> 
> From: Qiao Nuohan <address@hidden>
> 
> Hi, all
> 
> The last version is here:
> http://lists.gnu.org/archive/html/qemu-devel/2013-05/msg00803.html
> 
> Command 'dump-guest-memory' was introduced to dump guest's memory. But the
> vmcore's format is only elf32 or elf64. The message is here:
> http://lists.gnu.org/archive/html/qemu-devel/2012-04/msg03379.html
> 
> For migration, 'dump-guest-memory' is supposed to support compression feature.
> Because of the regression, the missing of compression feature, we post these
> patches to make 'dump-guest-memory' be able to dump guest's in kdump-
> compressed
> format. Then vmcore can be much smaller, and easily be delivered.
> 
> The kdump-compressed format is *linux specific* *linux standard* crash dump
> format used in kdump framework. The kdump-compressed format is readable only
> with the crash utility, and it can be smaller than the ELF format because of
> the compression support.
> 
> Note, similar to 'dump-guest-memory':
> 1. The guest should be x86 or x86_64. The other arch is not supported now.
> 2. If the OS is in the second kernel, gdb may not work well, and crash can
>    work by specifying '--machdep phys_addr=xxx' in the command line. The
>    reason is that the second kernel will update the page table, and we can
>    not get the page table for the first kernel.
> 3. The cpu's state is stored in QEMU note.
> 4. The vmcore are able to be compressed with zlib, lzo or snappy. zlib is
>    available by default, and option '--enable-lzo' or '--enable-snappy'
>    should be used with configure to make lzo or snappy available.
> 
> Changelog:
> Changes from v1 to v2:
> 1. Address Eric & Daniel's comment: fix manner of  string copy.
> 2. Address Eric's comment: replace reinventing new constants by using the
>    ready-made ones accoring.
> 3. Address Andreas's comment: remove useless include.
> 
> Qiao Nuohan (9):
>   Add API to manipulate dump_bitmap
>   Add API to manipulate cache_data
>   Move includes and struct definition to dump.h
>   Add API to create header of vmcore
>   Add API to create data of dump bitmap
>   Add API to create page
>   Add API to free buf used by creating header, bitmap and page
>   Add API to write header, bitmap and page into vmcore
>   Make monitor command 'dump-guest-memory' dump in kdump-compressed
>     format
> 
>  Makefile.target       |    2 +-
>  cache_data.c          |  121 +++++++
>  configure             |   50 +++
>  dump.c                |  877 ++++++++++++++++++++++++++++++++++++++++++++++--
> -
>  dump_bitmap.c         |  171 ++++++++++
>  hmp-commands.hx       |   12 +-
>  hmp.c                 |   23 ++-
>  include/cache_data.h  |   56 ++++
>  include/dump_bitmap.h |   60 ++++
>  include/sysemu/dump.h |  176 ++++++++++
>  qapi-schema.json      |   23 ++-
>  qmp-commands.hx       |    6 +-
>  12 files changed, 1527 insertions(+), 50 deletions(-)
>  create mode 100644 cache_data.c
>  create mode 100644 dump_bitmap.c
>  create mode 100644 include/cache_data.h
>  create mode 100644 include/dump_bitmap.h
>