6f56f0c4f1
Currently, for idle and frozen, action_store will hold 'reconfig_mutex' and call md_reap_sync_thread() to stop sync thread, however, this will cause deadlock (explained in the next patch). In order to fix the problem, following patch will release 'reconfig_mutex' and wait on 'resync_wait', like md_set_readonly() and do_md_stop() does. Consider that action_store() will set/clear 'MD_RECOVERY_FROZEN' unconditionally, which might cause unexpected problems, for example, frozen just set 'MD_RECOVERY_FROZEN' and is still in progress, while 'idle' clear 'MD_RECOVERY_FROZEN' and new sync thread is started, which might starve in progress frozen. A mutex is added to synchronize idle and frozen from action_store(). Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230529132037.2124527-4-yukuai1@huaweicloud.com
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.