Hi Everyone,
I was just checking if it was not missed in holidays and was received. :)
Thanks
Manish Mishra
On 21/12/22 12:14 am, manish.mishra wrote:
> Current logic assumes that channel connections on the destination side are
> always established in the same order as the source and the first one will
> always be the main channel followed by the multifid or post-copy
> preemption channel. This may not be always true, as even if a channel has a
> connection established on the source side it can be in the pending state on
> the destination side and a newer connection can be established first.
> Basically causing out of order mapping of channels on the destination side.
> Currently, all channels except post-copy preempt send a magic number, this
> patch uses that magic number to decide the type of channel. This logic is
> applicable only for precopy(multifd) live migration, as mentioned, the
> post-copy preempt channel does not send any magic number. Also, tls live
> migrations already does tls handshake before creating other channels, so
> this issue is not possible with tls, hence this logic is avoided for tls
> live migrations. This patch uses MSG_PEEK to check the magic number of
> channels so that current data/control stream management remains
> un-effected.
>
> v2:
> TLS does not support MSG_PEEK, so V1 was broken for tls live
> migrations. For tls live migration, while initializing main channel
> tls handshake is done before we can create other channels, so this
> issue is not possible for tls live migrations. In V2 added a check
> to avoid checking magic number for tls live migration and fallback
> to older method to decide mapping of channels on destination side.
>
> v3:
> 1. Split change in two patches, io patch for read_peek routines,
> migration patch for migration related changes.
> 2. Add flags to io_readv calls to get extra read flags like
> MSG_PEEK.
> 3. Some other minor fixes.
>
> v4:
> 1. Removed common *all_eof routines for read peek and added one
> specific to live migration.
> 2. Updated to use qemu_co_sleep_ns instead of qio_channel_yield.
> 3. Some other minor fixes.
>
> v5:
> 1. Handle busy-wait in migration_channel_read_peek due partial reads.
>
> v6:
> With earlier patch, multifd_load_setup was done only in
> migration_incoming_setup but if multifd channel is received before
> default channel, multifd channels will be uninitialized. Moved
> multifd_load_setup to migration_ioc_process_incoming.
>
>
> manish.mishra (2):
> io: Add support for MSG_PEEK for socket channel
> migration: check magic value for deciding the mapping of channels
>
> chardev/char-socket.c | 4 +--
> include/io/channel.h | 6 ++++
> io/channel-buffer.c | 1 +
> io/channel-command.c | 1 +
> io/channel-file.c | 1 +
> io/channel-null.c | 1 +
> io/channel-socket.c | 17 ++++++++-
> io/channel-tls.c | 1 +
> io/channel-websock.c | 1 +
> io/channel.c | 16 ++++++---
> migration/channel-block.c | 1 +
> migration/channel.c | 45 ++++++++++++++++++++++++
> migration/channel.h | 5 +++
> migration/migration.c | 54 ++++++++++++++++++++---------
> migration/multifd.c | 19 +++++-----
> migration/multifd.h | 2 +-
> migration/postcopy-ram.c | 5 +--
> migration/postcopy-ram.h | 2 +-
> scsi/qemu-pr-helper.c | 2 +-
> tests/qtest/tpm-emu.c | 2 +-
> tests/unit/test-io-channel-socket.c | 1 +
> util/vhost-user-server.c | 2 +-
> 22 files changed, 148 insertions(+), 41 deletions(-)
>