Re: [Qemu-devel] [RFC][PATCT 0/14 v4] dump memory when host pci device is used by guest

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2012-01-10 08:44, Wen Congyang wrote:
> Hi, Jan Kiszka
> Do you have any time to review this patchset?

Will try to find some.

BTW, the title of this cover letter is a bit misleading. This series is
about introducing a new, dedicated memory dump mechanism.

Jan

> 
> Thanks
> Wen Congyang
> 
> At 01/04/2012 01:44 PM, Wen Congyang Wrote:
>> Hi, all
>>
>> 'virsh dump' can not work when host pci device is used by guest. We have
>> discussed this issue here:
>> http://lists.nongnu.org/archive/html/qemu-devel/2011-10/msg00736.html
>>
>> We have determined to introduce a new command dump to dump memory. The core
>> file's format can be elf.
>>
>> Note:
>> 1. The guest should be x86 or x86_64. The other arch is not supported.
>> 2. If you use old gdb, gdb may crash. I use gdb-7.3.1, and it does not crash.
>> 3. 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.
>> 4. If the guest OS is 32 bit and the memory size is larger than 4G, the vmcore
>>    is elf64 format. You should use the gdb which is built with --enable-64-bit-bfd.
>>
>> Change from v3 to v4:
>> 1. support it to run asynchronously
>> 2. add API to cancel dumping and query dumping progress
>> 3. add API to control dumping speed
>> 4. auto cancel dumping when the user resumes vm, and the status is failed.
>>
>> Change from v2 to v3:
>> 1. address Jan Kiszka's comment
>>
>> Changes from v1 to v2:
>> 1. fix virt addr in the vmcore.
>>
>> Wen Congyang (14):
>>   Add API to create memory mapping list
>>   Add API to check whether a physical address is I/O address
>>   target-i386: implement cpu_get_memory_mapping()
>>   Add API to get memory mapping
>>   target-i386: Add API to write elf notes to core file
>>   target-i386: Add API to add extra memory mapping
>>   target-i386: add API to get dump info
>>   introduce a new monitor command 'dump' to dump guest's memory
>>   run dump at the background
>>   support detached dump
>>   support to cancel the current dumping
>>   support to set dumping speed
>>   support to query dumping status
>>   auto cancel dumping after vm state is changed to run
>>
>>  Makefile.target         |   11 +-
>>  cpu-all.h               |   18 +
>>  cpu-common.h            |    2 +
>>  dump.c                  |  796 +++++++++++++++++++++++++++++++++++++++++++++++
>>  dump.h                  |   14 +
>>  exec.c                  |   20 ++
>>  hmp-commands.hx         |   47 +++
>>  hmp.c                   |   24 ++
>>  hmp.h                   |    3 +
>>  memory_mapping.c        |  185 +++++++++++
>>  memory_mapping.h        |   39 +++
>>  monitor.c               |   10 +
>>  qapi-schema.json        |   54 ++++
>>  qmp-commands.hx         |  117 +++++++
>>  target-i386/arch-dump.c |  574 ++++++++++++++++++++++++++++++++++
>>  15 files changed, 1909 insertions(+), 5 deletions(-)
>>  create mode 100644 dump.c
>>  create mode 100644 dump.h
>>  create mode 100644 memory_mapping.c
>>  create mode 100644 memory_mapping.h
>>  create mode 100644 target-i386/arch-dump.c
>>
>>
> 

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