The for-loop might re-read the content of the memory the si_bits_global
points to on each iteration. Instead, just capture it for the sake of
consistency and use that instead.
Reviewed-by: Feng Tang <feng.tang@linux.alibaba.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
lib/sys_info.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/lib/sys_info.c b/lib/sys_info.c
index 496f9151c9b6..d542a024406a 100644
--- a/lib/sys_info.c
+++ b/lib/sys_info.c
@@ -58,11 +58,11 @@ int sysctl_sys_info_handler(const struct ctl_table *ro_table, int write,
char names[sizeof(sys_info_avail)];
struct ctl_table table;
unsigned long *si_bits_global;
+ unsigned long si_bits;
si_bits_global = ro_table->data;
if (write) {
- unsigned long si_bits;
int ret;
table = *ro_table;
@@ -81,9 +81,12 @@ int sysctl_sys_info_handler(const struct ctl_table *ro_table, int write,
char *delim = "";
int i, len = 0;
+ /* The access to the global value is not synchronized. */
+ si_bits = READ_ONCE(*si_bits_global);
+
names[0] = '\0';
for (i = 0; i < ARRAY_SIZE(si_names); i++) {
- if (*si_bits_global & si_names[i].bit) {
+ if (si_bits & si_names[i].bit) {
len += scnprintf(names + len, sizeof(names) - len,
"%s%s", delim, si_names[i].name);
delim = ",";
--
2.50.1