Re: [Qemu-devel] [PATCH v3 0/5] Add ignore-external migration capability

[Юрий Котов]

Hi,

I've sent a mail about this problem:
[RFC PATCH] QEMU may write to system_memory before guest starts

Regards,
Yury

06.03.2019, 13:47, "Yury Kotov" <address@hidden>:
> 05.03.2019, 21:06, "Dr. David Alan Gilbert" <address@hidden>:
>>  * Dr. David Alan Gilbert (address@hidden) wrote:
>>>   * Yury Kotov (address@hidden) wrote:
>>>   > Hi,
>>>   >
>>>   > The series adds a migration capability, which allows to skip shared RAM 
>>> blocks
>>>   > during the migration. It's useful for fast local migration. E.g. to 
>>> update QEMU
>>>   > for the running guests.
>>>
>>>   Queued
>>
>>  Hi Yury,
>>    The test is failing badly on aarch64 tcg for me (i.e. aarch64 tcg on
>>  x86); I'm going to keep it merged but keep the test disabled for now.
>>  Can you have a look to see if you can see what's going wrong?
>>
>>  Dave
>
> Hi,
>
> Yes, of course. I'll look at this.
>
> Regards,
> Yury
>
>>>   >
>>>   > Usage example:
>>>   > 1. Start source VM:
>>>   > qemu-system-x86 \
>>>   > -m 4G \
>>>   > -object 
>>> memory-backend-file,id=mem0,size=4G,share=on,mem-path=/dev/shm/mem0 \
>>>   > -numa node,memdev=mem0 \
>>>   > -qmp unix:/tmp/qemu-qmp-1.sock,server,nowait \
>>>   >
>>>   > 2. Start target VM:
>>>   > qemu-system-x86 \
>>>   > -m 4G \
>>>   > -object 
>>> memory-backend-file,id=mem0,size=4G,share=on,mem-path=/dev/shm/mem0 \
>>>   > -numa node,memdev=mem0 \
>>>   > -qmp unix:/tmp/qemu-qmp-2.sock,server,nowait \
>>>   > -incoming defer
>>>   >
>>>   > 3. Enable ignore-shared capability on both VMs:
>>>   > { "execute": "migrate-set-capabilities" , "arguments":
>>>   > { "capabilities": [ { "capability": "x-ignore-shared", "state": true } 
>>> ] } }
>>>   >
>>>   > 4. Start migration.
>>>   >
>>>   > Another use case I keep in mind is to migrate to file. Usage is very 
>>> similar.
>>>   >
>>>   > V2 to V3:
>>>   > * Split "migration: Introduce ignore-shared capability"
>>>   > * Serialize the capabilities as strings rather than as indexes
>>>   > * Don't allow to enable postcopy and ignore-shared together
>>>   > * Skip the test for OSs which don't have /dev/shm
>>>   > * Add a check whether shared RAM has been really skipped
>>>   >
>>>   > V1 to V2:
>>>   > * Keep migration stream compatibility
>>>   > * Reuse the existing code to ignore unwanted RAMBlocks
>>>   > * Add capability validation feature
>>>   > * ignore-external -> ignore-shared
>>>   >
>>>   > Regards,
>>>   > Yury
>>>   >
>>>   > Yury Kotov (5):
>>>   > exec: Change RAMBlockIterFunc definition
>>>   > migration: Introduce ignore-shared capability
>>>   > migration: Add an ability to ignore shared RAM blocks
>>>   > tests/migration-test: Add a test for ignore-shared capability
>>>   > migration: Add capabilities validation
>>>   >
>>>   > exec.c | 38 +++++------
>>>   > include/exec/cpu-common.h | 7 +-
>>>   > migration/migration.c | 14 ++++
>>>   > migration/migration.h | 5 +-
>>>   > migration/postcopy-ram.c | 48 +++++++------
>>>   > migration/ram.c | 110 ++++++++++++++++++++++--------
>>>   > migration/rdma.c | 9 ++-
>>>   > migration/savevm.c | 137 ++++++++++++++++++++++++++++++++++++++
>>>   > qapi/migration.json | 5 +-
>>>   > stubs/ram-block.c | 15 +++++
>>>   > tests/migration-test.c | 131 +++++++++++++++++++++++++++++-------
>>>   > util/vfio-helpers.c | 6 +-
>>>   > 12 files changed, 420 insertions(+), 105 deletions(-)
>>>   >
>>>   > --
>>>   > 2.20.1
>>>   >
>>>   >
>>>   --
>>>   Dr. David Alan Gilbert / address@hidden / Manchester, UK
>>  --
>>  Dr. David Alan Gilbert / address@hidden / Manchester, UK