From: Zhang Rui <rui.zhang@intel.com>
Date: Wed, 4 Mar 2026 00:30:12 +0000 (+0800)
Subject: tools/power turbostat: Fix illegal memory access when SMT is present and disabled
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=57d2371d52be1d574b33382bfbf8052485b99d8b;p=thirdparty%2Fkernel%2Flinux.git

tools/power turbostat: Fix illegal memory access when SMT is present and disabled

When SMT is present and disabled, turbostat may under-size
the thread_data array.  This can corrupt results or
cause turbostat to exit with a segmentation fault.

[lenb: commit message]
Fixes: a2b4d0f8bf07 ("tools/power turbostat: Favor cpu# over core#")
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
---

diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index 1a2671c28209..ae827485950d 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -9702,13 +9702,12 @@ void allocate_counters(struct counters *counters)
 {
 	int i;
 	int num_cores = topo.cores_per_node * topo.nodes_per_pkg * topo.num_packages;
-	int num_threads = topo.threads_per_core * num_cores;
 
-	counters->threads = calloc(num_threads, sizeof(struct thread_data));
+	counters->threads = calloc(topo.max_cpu_num + 1, sizeof(struct thread_data));
 	if (counters->threads == NULL)
 		goto error;
 
-	for (i = 0; i < num_threads; i++)
+	for (i = 0; i < topo.max_cpu_num + 1; i++)
 		(counters->threads)[i].cpu_id = -1;
 
 	counters->cores = calloc(num_cores, sizeof(struct core_data));