[PATCH v9 1/4] ring-buffer: Fix to update per-subbuf entries of persistent ring buffer

[Masami Hiramatsu (Google)]

From: Masami Hiramatsu (Google) <mhira...@kernel.org>

Since the validation loop in rb_meta_validate_events() updates
the same cpu_buffer->head_page->entries, the other subbuf entries
are not updated.
Fix to use head_page to update the entries field, since it is the
cursor in this loop.

Fixes: 5f3b6e839f3c ("ring-buffer: Validate boot range memory events")
Cc: sta...@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhira...@kernel.org>
---
 kernel/trace/ring_buffer.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index f16f053ef77d..353a5aa1b612 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -2053,7 +2053,7 @@ static void rb_meta_validate_events(struct 
ring_buffer_per_cpu *cpu_buffer)
 
                entries += ret;
                entry_bytes += local_read(&head_page->page->commit);
-               local_set(&cpu_buffer->head_page->entries, ret);
+               local_set(&head_page->entries, ret);
 
                if (head_page == cpu_buffer->commit_page)
                        break;