Changes

Merge tag 'trace-ringbuffer-v6.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull ring-buffer fixes from Steven Rostedt:

 - Fix ref counter of buffers assigned at boot up

   A tracing instance can be created from the kernel command line. If it
   maps to memory, it is considered permanent and should not be deleted,
   or bad things can happen. If it is not mapped to memory, then the
   user is fine to delete it via rmdir from the instances directory. But
   the ref counts assumed 0 was free to remove and greater than zero was
   not. But this was not the case. When an instance is created, it
   should have the reference of 1, and if it should not be removed, it
   must be greater than 1. The boot up code set normal instances with a
   ref count of 0, which could get removed if something accessed it and
   then released it. And memory mapped instances had a ref count of 1
   which meant it could be deleted, and bad things happen. Keep normal
   instances ref count as 1, and set memory mapped instances ref count
   to 2.

 - Protect sub buffer size (order) updates from other modifications

   When a ring buffer is changing the size of its sub-buffers, no other
   operations should be performed on the ring buffer. That includes
   reading it. But the locking only grabbed the buffer->mutex that keeps
   some operations from touching the ring buffer. It also must hold the
   cpu_buffer->reader_lock as well when updates happen as other paths
   use that to do some operations on the ring buffer.

* tag 'trace-ringbuffer-v6.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Fix reader locking when changing the sub buffer order
  ring-buffer: Fix refcount setting of boot mapped buffers