[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