Merge remote-tracking branch 'remotes/dgilbert-gitlab/tags/pull-migration-20210705a' into staging

Migration and virtiofs pull 2021-07-01 v2

Dropped Peter Xu's migration-test fix to reenable
most of the migration tests when uffd isn't available;
we're seeing at least one seg in github CI (on qemu-system-i386)
and Peter Maydell is reporting a hang on Openbsd.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

# gpg: Signature made Mon 05 Jul 2021 11:01:35 BST
# gpg:                using RSA key 45F5C71B4A0CB7FB977A9FA90516331EBC5BFDE7
# gpg: Good signature from "Dr. David Alan Gilbert (RH2) <dgilbert@redhat.com>" [full]
# Primary key fingerprint: 45F5 C71B 4A0C B7FB 977A  9FA9 0516 331E BC5B FDE7

* remotes/dgilbert-gitlab/tags/pull-migration-20210705a:
  migration/rdma: Use error_report to suppress errno message
  tests/migration: fix "downtime_limit" type when "migrate-set-parameters"
  tests/migration: parse the thread-id key of CpuInfoFast
  virtiofsd: Add an option to enable/disable posix acls
  virtiofsd: Switch creds, drop FSETID for system.posix_acl_access xattr
  virtiofsd: Add capability to change/restore umask
  virtiofsd: Add umask to seccom allow list
  virtiofsd: Add support for extended setxattr
  virtiofsd: Fix xattr operations overwriting errno
  virtiofsd: Fix fuse setxattr() API change issue
  virtiofsd: Don't allow file creation with FUSE_OPEN
  docs: describe the security considerations with virtiofsd xattr mapping
  virtiofsd: use GDateTime for formatting timestamp for debug messages
  migration: failover: continue to wait card unplug on error
  migration: move wait-unplug loop to its own function
  migration: Allow reset of postcopy_recover_triggered when failed
  migration: Move yank outside qemu_start_incoming_migration()
  migration: fix the memory overwriting risk in add_to_iovec
  tests: migration-test: Add dirty ring test

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>