From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 27927469849 for ; Tue, 4 Aug 2026 17:35:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785864953; cv=none; b=LFgydlUX6PiWnqRXu/6ZOiw++F20Qmp5egnSQjDJBPThmLhRljS2+btPTXt7GI6Dgd5a8++Dwr2HBM8Rb0sjFKuvigN9yHfgKb2ecRq4pXkJVkqh3T+o5ASQxuPsLL3+fYtjDRHW9sN9LVzyeH4TVXyul8K6GNTQDwNUwWhtzHg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785864953; c=relaxed/simple; bh=uMzwHd/79KnfXb1CvQ5QbhnBnqHsMVZMK60wQWtnkpY=; h=Date:To:From:Subject:Message-Id; b=HpFwMxuAYUL2od5NBPxxQ3Ko8hvTfp/vjNpgzPGLpe62sBf4vTU+sI6LIOm4OCDr7dK25N3JzsWpWXwqSaXPhtoNEFo19VLAl7xso8FBLAYINnDZO4Zwf2pU3JKIzpAaTPeZTAriCX73QX0XdEnLFTUASI6XYg29BoVTFgZoB14= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=cDzKqO36; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="cDzKqO36" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A719A1F000E9; Tue, 4 Aug 2026 17:35:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1785864951; bh=CvFV8JMq7oci5X7U1XjwP0Ov4hSKDJg7dhrZuumo0Rw=; h=Date:To:From:Subject; b=cDzKqO36xH3hxR+fI6sSpcFlc1G7/Jp8XTXqr/IjxqPdHONmqQJ33FvQ9fnMzoaOV rtgFORFpMiggydFirm8BXkgW8Lo5z1QrZl+3q4NfPotNhxcu9ovAgw73eSOPZ85CRL 5+a0wZZTv90eigI5N4xpEfd71QSI7EEQyJJEkhJg= Date: Tue, 04 Aug 2026 10:35:51 -0700 To: mm-commits@vger.kernel.org,vbabka@kernel.org,surenb@google.com,shuah@kernel.org,rppt@kernel.org,mhocko@suse.com,ljs@kernel.org,liam@infradead.org,david@kernel.org,warren.xiong@ugreen.com,akpm@linux-foundation.org From: Andrew Morton Subject: + selftests-mm-read-memory-information-without-popen.patch added to mm-new branch Message-Id: <20260804173551.A719A1F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: selftests/mm: read memory information without popen has been added to the -mm mm-new branch. Its filename is selftests-mm-read-memory-information-without-popen.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-mm-read-memory-information-without-popen.patch This patch will later appear in the mm-new branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Note, mm-new is a provisional staging ground for work-in-progress patches, and acceptance into mm-new is a notification for others take notice and to finish up reviews. Please do not hesitate to respond to review feedback and post updated versions to replace or incrementally fixup patches in mm-new. The mm-new branch of mm.git is not included in linux-next If a few days of testing in mm-new is successful, the patch will me moved into mm.git's mm-unstable branch, which is included in linux-next Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: Warren Xiong Subject: selftests/mm: read memory information without popen Date: Tue, 4 Aug 2026 20:16:58 +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/1785845818-3131-1-git-send-email-warren.xiong@ugreen.com Signed-off-by: Warren Xiong Acked-by: David Hildenbrand (Arm) Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Mike Rapoport Cc: Shuah Khan Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- tools/testing/selftests/mm/compaction_test.c | 40 +++++++++-------- 1 file changed, 22 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 @@ -29,30 +29,34 @@ 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]; + int found = 0; + 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) && found != 2) { + if (sscanf(buffer, "MemFree: %lu kB", memfree) == 1 || + sscanf(buffer, "Hugepagesize: %lu kB", hugepagesize) == 1) + found++; } - pclose(cmdfile); - *hugepagesize = atoll(buffer); + if (ferror(file)) + ksft_print_msg("Failed to read /proc/meminfo: %s\n", + strerror(errno)); + else if (found != 2) + ksft_print_msg("Failed to parse /proc/meminfo\n"); + else + ret = 0; - return 0; + fclose(file); + return ret; } int prereq(void) _ Patches currently in -mm which might be from warren.xiong@ugreen.com are selftests-mm-read-memory-information-without-popen.patch tools-mm-prevent-page_owner_sort-from-truncating-input.patch