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 CB95E453A24 for ; Tue, 4 Aug 2026 23:55:14 +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=1785887716; cv=none; b=QXSMRUutobPmo1GFFxp5fd3iN50NJ2C5oiHLzEy91DEedlqanj6H/pVtNohhuDLAv8DcCVrEyFXiVnym4YiTrXqYQrNUDId5uM/B1SFedDKPMJWeXsMdX9w5awA1UovimfACmFYBvHLSicpq5y1cH4efOJvYy/7jMBrKibnyY2Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785887716; c=relaxed/simple; bh=0Kf3IJ5NmAE6Lohcu9G6RkOi6WaGfoLZRlqJjFq+J7E=; h=Date:To:From:Subject:Message-Id; b=Ldx3Ni4LiJ+VerTQBNBeGakfj/jDQB2b5kkEzmGKj4Q7kibj6qAdjAVpGiOXxk1nxSGP1kAJlYDKcMHyFk/Uz0m5c2Xvp/ZhHNCzbTdNFjsUsmXk8xi2Pmvo4hXxal9Q6FiiGCWPMw9jt112r9uFQWDiV52SOiKpv7I/5+2NstM= 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=jZAFa3Le; 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="jZAFa3Le" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 886BB1F00A3A; Tue, 4 Aug 2026 23:55:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1785887714; bh=8RDMjESjmWecmuo4j5ywAdnzprXTf5sjQJe4vsGnOyU=; h=Date:To:From:Subject; b=jZAFa3LeA8MBM9SUIn7kJaPiGKr7Q0iD/GQ54DIzYMQOPXnfHBc9DOcb3m1jjsIRX fDk4YbYWpcwK5zsZDQWaAVy6b5I5oqOsdXvoI2wC5RCv0Z6dU6SgcJaleimKEpvpPc ZZ2gDt08AQM3TrAwbOa9RduTWxbT4Otog81M9fmE= Date: Tue, 04 Aug 2026 16:55:14 -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-unstable branch Message-Id: <20260804235514.886BB1F00A3A@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-unstable 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-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 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) Acked-by: Mike Rapoport (Microsoft) Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko 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