From: Vincent Donnefort Date: Wed, 29 Jul 2026 13:36:09 +0000 (+0100) Subject: ring-buffer: Fix reader page read offset for remote buffers X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=78cd56c2a9d2e8da763cea3b06b636266ca66911;p=thirdparty%2Flinux.git ring-buffer: Fix reader page read offset for remote buffers A page swapped in by __rb_get_reader_page_from_remote() retains its stale read offset, causing subsequent reads to skip events or read past valid data. Fix it. Link: https://patch.msgid.link/20260729133609.4022734-1-vdonnefort@google.com Fixes: fbd1743ecba1 ("ring-buffer: Add non-consuming read for ring-buffer remotes") Signed-off-by: Vincent Donnefort Reviewed-by: Keir Fraser Tested-by: Keir Fraser Signed-off-by: Steven Rostedt --- diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 804ccae694d2..78d3875a47a5 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -5783,6 +5783,7 @@ __rb_get_reader_page_from_remote(struct ring_buffer_per_cpu *cpu_buffer) cpu_buffer->head_page = new_head; cpu_buffer->reader_page = new_reader; + cpu_buffer->reader_page->read = 0; cpu_buffer->pages = &new_head->list; cpu_buffer->read_stamp = new_reader->page->time_stamp; cpu_buffer->lost_events = cpu_buffer->meta_page->reader.lost_events;