From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 6866915746F for ; Thu, 4 Sep 2025 14:52:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756997565; cv=none; b=r1XflU5vsMboazGMyEXY6Q9AyrLnOgF6RECsu+TURo5QqoAE/QzSBWbSJb6QlVgz6Sfr0lBLCci1PfCeR9yabKOziznSAnzdYeEXYpp3fuDZT0axcDSxE6QvHbHkgjt/zZy/f06cjRBPywglwZP9JdQyBYtIjcMJ4HId+zHIZaw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756997565; c=relaxed/simple; bh=D561VjwYH9RA6r2Rugv4ZQ4heaNI4ENsoElZA2pFl7c=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=O0cp3Qnet7/cU0aE0bNLogfR5YPelR9XLcsm8bkUA1jOW74kbwXKz+PXhONaRO5pqyeDWRg4MqIX1pX1RXjnF2b8b/RGh6UG7rYj0WfkGMLReRgb5ZyccOm+fLPrXIEMDfsVLxwbyW0rSpTcP56PFZXruc++KfImdhwgZYDWsDc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=VP2sT/EA; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="VP2sT/EA" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1756997562; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=BazxnC+Wcptnkdd+tPophW9XIDvM64THaSvkRAFx9Mg=; b=VP2sT/EAUXPlLqopVQROh9M94Ion1zcudzMoJnrel8N+jIfL1KCXIxEfFDFMPx021vVhKV 11a/AjixhxvrzFLjTiaMWRw2bZz6sUwc0yuPsTF9sVn4wFR0erR7nIGlNe82Uzkd0o7Nd+ 2RXp0vxtKXVDNTEbED+VOsrdKfLXulY= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-486-1O0OaGzTPK-kKLpbyr87uA-1; Thu, 04 Sep 2025 10:52:39 -0400 X-MC-Unique: 1O0OaGzTPK-kKLpbyr87uA-1 X-Mimecast-MFC-AGG-ID: 1O0OaGzTPK-kKLpbyr87uA_1756997556 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 631281800291; Thu, 4 Sep 2025 14:52:36 +0000 (UTC) Received: from gmail.com (dell-per7425-02.rhts.eng.pek2.redhat.com [10.73.116.18]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id C81361955F24; Thu, 4 Sep 2025 14:52:29 +0000 (UTC) Date: Thu, 4 Sep 2025 22:52:25 +0800 From: Chunyu Hu To: David Hildenbrand Cc: akpm@linux-foundation.org, shuah@kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, mhocko@suse.com Subject: [RESEND] Re: [PATCH 1/2] selftests/mm: fix hugepages cleanup too early Message-ID: References: <20250827075209.2347015-1-chuhu@redhat.com> <20250827075209.2347015-2-chuhu@redhat.com> <87956f34-e6b0-4d03-b30e-56be4f6b84f1@redhat.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87956f34-e6b0-4d03-b30e-56be4f6b84f1@redhat.com> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 On Wed, Aug 27, 2025 at 01:41:34PM +0200, David Hildenbrand wrote: > On 27.08.25 09:52, Chunyu Hu wrote: > > The nr_hugepgs variable is used to keep the original nr_hugepages at the > > hugepage setup step at test beginning. After userfaultfd test, a cleaup is > > executed, both /sys/kernel/mm/hugepages/hugepages-*/nr_hugepages and > > /proc/sys//vm/nr_hugepages are reset to 'original' value before userfaultfd > > test starts. > > > > Issue here is the value used to restore /proc/sys/vm/nr_hugepages is > > nr_hugepgs which is the initial value before the vm_runtests.sh runs, not > > the value before userfaultfd test starts. 'va_high_addr_swith.sh' tests > > runs after that will possibly see no hugepages available for test, and got > > EINVAL when mmap(HUGETLB), making the result invalid. > > > > And before pkey tests, nr_hugepgs is changed to be used as a temp variable > > to save nr_hugepages before pkey test, and restore it after pkey tests > > finish. The original nr_hugepages value is not tracked anymore, so no way > > to restore it after all tests finish. > > > > Add a new variable nr_hugepgs_origin to save the original nr_hugepages, and > > and restore it to nr_hugepages after all tests finish. And change to use > > the nr_hugepgs variable to save the /proc/sys/vm/nr_hugeages after hugepage > > setup, it's also the value before userfaultfd test starts, and the correct > > value to be restored after userfaultfd finishes. The va_high_addr_switch.sh > > broken will be resolved. > > > > Signed-off-by: Chunyu Hu > > --- > > tools/testing/selftests/mm/run_vmtests.sh | 9 +++++++-- > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/tools/testing/selftests/mm/run_vmtests.sh b/tools/testing/selftests/mm/run_vmtests.sh > > index 471e539d82b8..f1a7ad3ec6a7 100755 > > --- a/tools/testing/selftests/mm/run_vmtests.sh > > +++ b/tools/testing/selftests/mm/run_vmtests.sh > > @@ -172,13 +172,13 @@ fi > > # set proper nr_hugepages > > if [ -n "$freepgs" ] && [ -n "$hpgsize_KB" ]; then > > - nr_hugepgs=$(cat /proc/sys/vm/nr_hugepages) > > + nr_hugepgs_origin=$(cat /proc/sys/vm/nr_hugepages) > > I'd call this "orig_nr_hugepgs". [RESEND to add back the unexpectedly dropped mail list, sorry for that] Hi David, Thank you for your review and valuable feedback. I will rename it with a v2 and resend the two patches. > > But it's a shame that the naming is then out of sync with nr_size_hugepgs? nr_size_hugepgs is for uffd-wp-mremap, the test need all sizes hugepages, it's used to save and restore the nr_hugepagees of all sizes of hugepages, it's a test case setup, not like nr_hugepgs which is a global/general setup. They are not the same kind, maybe they don't need to be aligned. > > > > needpgs=$((needmem_KB / hpgsize_KB)) > > tries=2 > > while [ "$tries" -gt 0 ] && [ "$freepgs" -lt "$needpgs" ]; do > > lackpgs=$((needpgs - freepgs)) > > echo 3 > /proc/sys/vm/drop_caches > > - if ! echo $((lackpgs + nr_hugepgs)) > /proc/sys/vm/nr_hugepages; then > > + if ! echo $((lackpgs + nr_hugepgs_origin)) > /proc/sys/vm/nr_hugepages; then > > echo "Please run this test as root" > > exit $ksft_skip > > fi > > @@ -189,6 +189,7 @@ if [ -n "$freepgs" ] && [ -n "$hpgsize_KB" ]; then > > done < /proc/meminfo > > tries=$((tries - 1)) > > done > > + nr_hugepgs=$(cat /proc/sys/vm/nr_hugepages) > > if [ "$freepgs" -lt "$needpgs" ]; then > > printf "Not enough huge pages available (%d < %d)\n" \ > > "$freepgs" "$needpgs" > > @@ -532,6 +533,10 @@ CATEGORY="page_frag" run_test ./test_page_frag.sh aligned > > CATEGORY="page_frag" run_test ./test_page_frag.sh nonaligned > > +if [ "${HAVE_HUGEPAGES}" = 1 ]; then > > + echo "$nr_hugepgs_origin" > /proc/sys/vm/nr_hugepages > > +fi > > FWIW, I think the tests should maybe be doing that (save+configure+restore) > themselves, like we do with THP settings through. > > thp_save_settings() > thp_write_settings() > > and friends. For this va_high_addr_switch test, looks like we can do the save_setting, write_setting and restore_setting in the va_high_addr_switch.sh. > > This is not really something run_vmtests.sh should bother with. > > A bigger rework, though ... Totally agree, with the c interface to do that is better. then the vm_runtest.sh would be clean. It's a bigger rework outside of this topic. > > -- > Cheers > > David / dhildenb >