On Fri, 2 Sep 2022 11:47:58 +0800 lijiazi <jqqlijiazi@xxxxxxxxx> wrote: > Yes, I'm thinking this may be a race issue too. > But I didn't find race point through code review. I think I may have found it. Can you test this patch? [ Disclaimer, I did not even try to compile it ] -- Steve diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index d59b6a328b7f..0f47e68fee9b 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -4580,6 +4580,10 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer) goto again; out: + /* If the commit is past the end of page, a writer is still updating it */ + if (reader && rb_page_size(reader) > BUF_PAGE_SIZE) + reader = NULL; + /* Update the read_stamp on the first event */ if (reader && reader->read == 0) cpu_buffer->read_stamp = reader->page->time_stamp;
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