In commit c091a0bc we removed
the use of the HASH_ macros for inserting into
buf_pool.page_hash, or accessing buf_page_t::hash.

However, the binary buddy allocator for block->page.zip.data would
still use the HASH_ macros. HASH_INSERT and not HASH_DELETE would reset
the next-block pointer to the null pointer. Our replacement of
HASH_DELETE() will reset the next-block pointer, and the replacement of
HASH_INSERT() assumes that the pointer is the null pointer.

buf_LRU_block_free_non_file_page(): Assert that the next-block pointer
is the null pointer.

buf_buddy_block_free(): Reset the pointer before invoking
buf_LRU_block_free_non_file_page(). Without this, the added
assertion would fail in the test encryption.innochecksum.

old ftp.pcre.org is apparently down,
www.pcre.org says to use github as the primary download location

This is follow-up to commit 1193a793.
We will set innodb_use_native_aio=OFF by default also in mariadb-backup
when running on a potentially affected kernel.

* Fix error handling NULL-pointer reference
* Add mtr-suppression on galera_ssl_upgrade

* Fix error handling NULL-pointer reference
* Add mtr-suppression on galera_ssl_upgrade

* Fix error handling NULL-pointer reference
* Add mtr-suppression on galera_ssl_upgrade

Use better error message when KILL fails even in case TOI
fails.

* Fix error handling NULL-pointer reference
* Add mtr-suppression on galera_ssl_upgrade

fix test failures on rpm-centos73-ppc64

followup for 401ff699

it's https://gcc.gnu.org/bugzilla/show_bug.cgi?id=7302
fixed in 2011
affects fmtlib: https://github.com/fmtlib/fmt/issues/1936

Mutex order violation when wsrep bf thread kills a conflicting trx,
the stack is

          wsrep_thd_LOCK()
          wsrep_kill_victim()
          lock_rec_other_has_conflicting()
          lock_clust_rec_read_check_and_lock()
          row_search_mvcc()
          ha_innobase::index_read()
          ha_innobase::rnd_pos()
          handler::ha_rnd_pos()
          handler::rnd_pos_by_record()
          handler::ha_rnd_pos_by_record()
          Rows_log_event::find_row()
          Update_rows_log_event::do_exec_row()
          Rows_log_event::do_apply_event()
          Log_event::apply_event()
          wsrep_apply_events()

and mutexes are taken in the order

          lock_sys->mutex -> victim_trx->mutex -> victim_thread->LOCK_thd_data

When a normal KILL statement is executed, the stack is

          innobase_kill_query()
          kill_handlerton()
          plugin_foreach_with_mask()
          ha_kill_query()
          THD::awake()
          kill_one_thread()

        and mutexes are

          victim_thread->LOCK_thd_data -> lock_sys->mutex -> victim_trx->mutex

This patch is the plan D variant for fixing potetial mutex locking
order exercised by BF aborting and KILL command execution.

In this approach, KILL command is replicated as TOI operation.
This guarantees total isolation for the KILL command execution
in the first node: there is no concurrent replication applying
and no concurrent DDL executing. Therefore there is no risk of
BF aborting to happen in parallel with KILL command execution
either. Potential mutex deadlocks between the different mutex
access paths with KILL command execution and BF aborting cannot
therefore happen.

TOI replication is used, in this approach,  purely as means
to provide isolated KILL command execution in the first node.
KILL command should not (and must not) be applied in secondary
nodes. In this patch, we make this sure by skipping KILL
execution in secondary nodes, in applying phase, where we
bail out if applier thread is trying to execute KILL command.
This is effective, but skipping the applying of KILL command
could happen much earlier as well.

This also fixed unprotected calls to wsrep_thd_abort
that will use wsrep_abort_transaction. This is fixed
by holding THD::LOCK_thd_data while we abort transaction.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>

Revert "MDEV-23328 Server hang due to Galera lock conflict resolution"

This reverts commit eac8341d.

add a test case

MDEV-26742 Assertion `field->type_handler() == this' failed in FixedBinTypeBundle<NATIVE_LEN, MAX_CHAR_LEN>::Type_handler_fbt::stored_field_cmp_to_item

The bug was fixed in 10.5 using INET6 specific tests.

This bugs adds only UUID specific tests (no code changes).

UUID values

  llllllll-mmmm-Vhhh-vsss-nnnnnnnnnnnn

are now stored as

  nnnnnnnnnnnn-vsss-Vhhh-mmmm-llllllll

inside the record:

- the groups (segments separated by dash) are reordered right-to-left.
- the bytes inside the groups are not reordered (stored as before,
  in big-endian format).

This provides a better sorting order: the earlier UUID was generated,
the higher it appears in the ORDER BY output.

Also, this change enables a good key prefix compression,
because the constant part is now in the beginning, while
the non-constant part (the timestamp) is in the end.