On Wed, Sep 13, 2023 at 06:03:15PM -0700, Stephen Brennan wrote:
> This can be used from QMP command line as "-R" to mirror the
> corresponding flag for makedumpfile. This enables the kdump_reassembled
> flag introduced in the previous patch.
>
> Signed-off-by: Stephen Brennan <stephen.s.bren...@oracle.com>
> ---
> dump/dump-hmp-cmds.c | 8 +++++++-
> dump/dump.c | 12 +++++++++++-
> hmp-commands.hx | 7 +++++--
> qapi/dump.json | 14 +++++++++++++-
> 4 files changed, 36 insertions(+), 5 deletions(-)
> diff --git a/qapi/dump.json b/qapi/dump.json
> index 4ae1f722a9..9cc7c3ea93 100644
> --- a/qapi/dump.json
> +++ b/qapi/dump.json
> @@ -69,6 +69,18 @@
> # to dump all guest's memory, please specify the start @begin and
> # @length
> #
> +# @reassembled: if false (the default), the kdump output formats will use the
> +# "makedumpfile flattened" variant of the format, which is less broadly
> +# compatible with analysis tools. The flattened dump can be reassembled
> +# after the fact using the command "makedumpfile -R". If true, Qemu
> +# attempts to generate the standard kdump format. This requires a
> +# seekable file as output -- if the output file is not seekable, then
> +# the flattened format is still generated. The standard format is more
> +# broadly compatible with debugging tools, but generating it requires a
> +# seekable output file descriptor, and could use more system memory due
> +# to page cache utilization. This should be left unspecified for
> non-kdump
> +# output formats.
> +#
> # @format: if specified, the format of guest memory dump. But non-elf
> # format is conflict with paging and filter, ie. @paging, @begin
> # and @length is not allowed to be specified with non-elf @format
> @@ -89,7 +101,7 @@
> { 'command': 'dump-guest-memory',
> 'data': { 'paging': 'bool', 'protocol': 'str', '*detach': 'bool',
> '*begin': 'int', '*length': 'int',
> - '*format': 'DumpGuestMemoryFormat'} }
> + '*reassembled': 'bool', '*format': 'DumpGuestMemoryFormat'} }
The 'reassembled' flag is changing the meaning of 3 out of the 5
'format' enum values. IMHO, we should just be adding new formats
instead of changing the meaning of existing formats. It is a shame
we have the current 'kdump' naming prefix, but we're stuck with
that for backwards compat, we need a new prefix. I'd suggest
'kdump-raw'. eg
#
# @DumpGuestMemoryFormat:
#
# An enumeration of guest-memory-dump's format.
#
# @elf: elf format
#
# @kdump-zlib: makedumpfile flattened, kdump-compressed format with
zlib-compressed
#
# @kdump-lzo: makedumpfile flattened, kdump-compressed format with
lzo-compressed
#
# @kdump-snappy: makedumpfile flattened, kdump-compressed format with
snappy-compressed
#
# @kdump-raw-zlib: raw assembled kdump-compressed format with zlib-compressed
(since 8.2)
#
# @kdump-raw-lzo: raw assembled kdump-compressed format with lzo-compressed
(since 8.2)
#
# @kdump-raw-snappy: raw assembled kdump-compressed format with
snappy-compressed (since 8.2)
#
# @win-dmp: Windows full crashdump format, can be used instead of ELF
# converting (since 2.13)
#
# Since: 2.0
##
{ 'enum': 'DumpGuestMemoryFormat',
'data': [ 'elf',
'kdump-zlib', 'kdump-lzo', 'kdump-snappy',
'kdump-raw-zlib', 'kdump-raw-lzo', 'kdump-raw-snappy',
'win-dmp' ] }
With regards,
Daniel
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