93e71edfd9
The reference needs to keep the instance memory around, but also the instance lock must remain valid. Users will take the lock, check registration status and release the lock. mutex_destroy() etc. belong in the same place as the freeing of the memory. Unfortunately lockdep_unregister_key() sleeps so we need to switch the an rcu_work. Note that the problem is a bit hard to repro, because devlink_pernet_pre_exit() iterates over registered instances. AFAIU the instances must get devlink_free()d concurrently with the namespace getting deleted for the problem to occur. Reported-by: syzbot+d94d214ea473e218fc89@syzkaller.appspotmail.com Reported-by: syzbot+9f0dd863b87113935acf@syzkaller.appspotmail.com Fixes: 9053637e0da7 ("devlink: remove the registration guarantee of references") Reviewed-by: Jiri Pirko <jiri@nvidia.com> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Link: https://lore.kernel.org/r/20230111042908.988199-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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.