The unload_page callback expects the return value of load_page() as its
argument: ret = load_page(va); unload(ret). Fix the rollback code in
simple_ring_buffer_init_mm() where the descriptor's VA is used instead
of the loaded page address.
Link: https://patch.msgid.link/20260512141614.1759430-1-vdonnefort@google.com
Fixes: 635923081c ("tracing: load/unload page callbacks for simple_ring_buffer")
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
nr_subbufs in the ring buffer metadata is always initialized to zero
because it is assigned from cpu_buffer->nr_pages before the page
initialization loop has run. While nr_subbufs is not currently read
by the kernel, it should reflect the actual buffer geometry in the
meta page for correctness.
Move the assignment after the page loop so that cpu_buffer->nr_pages
holds the final count.
Link: https://patch.msgid.link/20260512135420.99194-1-devnexen@gmail.com
Fixes: 34e5b958bd ("tracing: Introduce simple_ring_buffer")
Reviewed-by: Vincent Donnefort <vdonnefort@google.com>
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: David Carlier <devnexen@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
