d78ab79270
When the ring buffer is being resized, it can cause side effects to the running tracer. For instance, there's a race with irqsoff tracer that swaps individual per cpu buffers between the main buffer and the snapshot buffer. The resize operation modifies the main buffer and then the snapshot buffer. If a swap happens in between those two operations it will break the tracer. Simply stop the running tracer before resizing the buffers and enable it again when finished. Link: https://lkml.kernel.org/r/20231205220010.748996423@goodmis.org Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Fixes: 3928a8a2d9808 ("ftrace: make work with new ring buffer") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.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.