From ade2105e748f85eb026d26701091213855aea633 Mon Sep 17 00:00:00 2001 From: Elijah Wright Date: Wed, 20 Aug 2025 22:39:07 -0700 Subject: [PATCH] tracing: Move buffer in trace_seq to end of struct TRACE_SEQ_BUFFER_SIZE is dependent on the architecture for its size. on 64-bit systems, it is 8148 bytes. forced 8-byte alignment in size_t and seq_buf means that trace_seq is 8200 bytes on 64-bit systems. moving the buffer to the end of the struct fixes the issue. there shouldn't be any side effects, i.e. pointer arithmetic on trace_seq Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Link: https://lore.kernel.org/20250821053917.23301-1-git@elijahs.space Signed-off-by: Elijah Wright Signed-off-by: Steven Rostedt (Google) --- include/linux/trace_seq.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/trace_seq.h b/include/linux/trace_seq.h index a93ed5ac3226..557780fe1c77 100644 --- a/include/linux/trace_seq.h +++ b/include/linux/trace_seq.h @@ -21,10 +21,10 @@ (sizeof(struct seq_buf) + sizeof(size_t) + sizeof(int))) struct trace_seq { - char buffer[TRACE_SEQ_BUFFER_SIZE]; struct seq_buf seq; size_t readpos; int full; + char buffer[TRACE_SEQ_BUFFER_SIZE]; }; static inline void -- 2.47.3