--- ptdump-1.0.3/ptdump.c.orig

+++ ptdump-1.0.3/ptdump.c

@@ -502,6 +502,14 @@ cmd_ptdump(void)

 		return;

 	}

+	/* 

+	 * Set the gdb scope to ensure that the appropriate ring_buffer 

+	 * structure is selected. 

+	 */

+	if (kernel_symbol_exists("perf_mmap_to_page"))

+		gdb_set_crash_scope(symbol_value("perf_mmap_to_page"), 

+			"perf_mmap_to_page");

+

 	online_cpus = get_cpus_online();

 	list_len = sizeof(struct pt_info)*kt->cpus;

 	pt_info_list = malloc(list_len);