[to-be-updated] selftests-mm-read-memory-information-without-popen.patch removed from -mm tree
Andrew Morton <[email protected]> Tue, 04 Aug 2026 10:35:03 -0700
| Newsgroups | org.kernel.vger.mm-commits |
|---|---|
| Message-ID | <[email protected]> |
The quilt patch titled
Subject: selftests/mm: read memory information without popen
has been removed from the -mm tree. Its filename was
selftests-mm-read-memory-information-without-popen.patch
This patch was dropped because an updated version will be issued
------------------------------------------------------
From: Warren Xiong <[email protected]>
Subject: selftests/mm: read memory information without popen
Date: Mon, 3 Aug 2026 09:30:15 +0800
read_memory_info() invokes two shell pipelines to obtain MemFree and
Hugepagesize from /proc/meminfo. It does not check whether popen()
returns NULL before passing the result to fgets(), and it does not call
pclose() when fgets() fails.
Open /proc/meminfo directly and obtain both values in a single pass. This
removes the unchecked NULL path, closes the file on all paths, and avoids
dependencies on external commands.
The compaction test continues to pass after this change.
Link: https://lore.kernel.org/[email protected]
Signed-off-by: Warren Xiong <[email protected]>
Reviewed-by: Andrew Morton <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Liam R. Howlett <[email protected]>
Cc: Lorenzo Stoakes <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Suren Baghdasaryan <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---
tools/testing/selftests/mm/compaction_test.c | 47 ++++++++++-------
1 file changed, 29 insertions(+), 18 deletions(-)
--- a/tools/testing/selftests/mm/compaction_test.c~selftests-mm-read-memory-information-without-popen
+++ a/tools/testing/selftests/mm/compaction_test.c
@@ -7,6 +7,7 @@
* allocated.
*/
+#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/mman.h>
@@ -29,30 +30,40 @@ struct map_list {
int read_memory_info(unsigned long *memfree, unsigned long *hugepagesize)
{
- char buffer[256] = {0};
- char *cmd = "cat /proc/meminfo | grep -i memfree | grep -o '[0-9]*'";
- FILE *cmdfile = popen(cmd, "r");
-
- if (!(fgets(buffer, sizeof(buffer), cmdfile))) {
- ksft_print_msg("Failed to read meminfo: %s\n", strerror(errno));
+ char buffer[256];
+ bool memfree_found = false;
+ bool hugepagesize_found = false;
+ FILE *file;
+ int ret = -1;
+
+ file = fopen("/proc/meminfo", "r");
+ if (!file) {
+ ksft_print_msg("Failed to open /proc/meminfo: %s\n",
+ strerror(errno));
return -1;
}
- pclose(cmdfile);
-
- *memfree = atoll(buffer);
- cmd = "cat /proc/meminfo | grep -i hugepagesize | grep -o '[0-9]*'";
- cmdfile = popen(cmd, "r");
-
- if (!(fgets(buffer, sizeof(buffer), cmdfile))) {
- ksft_print_msg("Failed to read meminfo: %s\n", strerror(errno));
- return -1;
+ while (fgets(buffer, sizeof(buffer), file)) {
+ if (sscanf(buffer, "MemFree: %lu kB", memfree) == 1)
+ memfree_found = true;
+ else if (sscanf(buffer, "Hugepagesize: %lu kB",
+ hugepagesize) == 1)
+ hugepagesize_found = true;
+
+ if (memfree_found && hugepagesize_found) {
+ ret = 0;
+ break;
+ }
}
- pclose(cmdfile);
- *hugepagesize = atoll(buffer);
+ if (ferror(file))
+ ksft_print_msg("Failed to read /proc/meminfo: %s\n",
+ strerror(errno));
+ else if (ret)
+ ksft_print_msg("Failed to parse /proc/meminfo\n");
- return 0;
+ fclose(file);
+ return ret;
}
int prereq(void)
_
Patches currently in -mm which might be from [email protected] are
tools-mm-prevent-page_owner_sort-from-truncating-input.patch