From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793841508; b=p2bJXTFokOgCfzDW6xyT3cbGtvjqFkzSnxNUdy5wLxOFUtdlJoW9ydVIkjVgAfXpJYgD 4ZspYA3fbjK9wmrUqaowWKufLB+7sGwOkfiI+vNFvXt2FRHK8sfWvNEYVOfj4KPMwG8jX vBtgSDZfl0IZv9e0qCI8cr9iaRrqJSUbsFzBG5p/FEnR0DZQV05RPEAoE1K+0zvGGa/NA 6IQ4g3i5F2RHE6gef9OMC3U1ZLRv6d8nUXbx1G2M2RAdrg49EyF4IZcKQgHyJqzrcPYHQ +5B0kNoq1Q1ldPPOyCCxDYNz1WvAjWAkEaowEjnyPInqkRqyT/cjyf0xEOZVYytGTEg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793841508; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: MIME-Version:Content-Transfer-Encoding; bh=mQmK1VyNyRInh3bcu1F6pkwNvgg2G6ZMbyKt5yTapqk=; b=tWUgVdAUtHLAudXp9TbJ5Ahz4quDDY8gs2rdtvnIX4zIhqKTl9Tnhg0bwvxqbGVolFAE qUx5Bblp4tq7nsixfZfRgxLNPxTg3GN9it0xSy11oBeD0Ku+m1IRLcEuVauUSmeGp/gt6 R0TB8UoYIU+nv4BHjhcofM7d79ta35XexywJKSnjcJwjkYlsYJ+kvNpqypFe8M7QZGzdj e+WffjsVwNIRTyzR0nyGGjvIJYbzCC77QHcoL+4UQI/Ep6vmmCGhyaYXIaxZQgVdX39OH 1QMBvmTESj50Zr8WFcUR/LD/hv3faEVup1fsBYLFJOv5m3y123t3zTy7jP9CZ5dU5wQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="UUUFD0/R"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B1DFF606D82B; Thu, 5 Nov 2026 01:18:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=UUUFD0/R Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1531E1F00A20; Thu, 5 Nov 2026 01:18:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793841507; bh=mQmK1VyNyRInh3bcu1F6pkwNvgg2G6ZMbyKt5yTapqk=; h=From:To:Cc:Subject:Date; b=UUUFD0/RgyXitm6KMRBEe87kCtHttmgDX46T/atU2r8acWM3dB/s5NllRUEMpNEiK MU6WSNC2Acb8ZjI7ca8uVCP7sKxODSHEukTJoVUU5H5HhkiNUEmceiK9xQf9i/lG3+ L3G4RTgZjbY2tRV3wXkdQdkjyzXMhJXESbPL3hTac1K7cWvu6hbHwuTUS0R2gygPLE 2wQ/PdHfOtCkuOgpm82s9gSuhZzkEqUkA62y3uHLmGIP9JfpEvCRUPcY8Lpghhv22/ htt2GoRebJ9LMjxCGPTc1Ti9LJRFq1ZMviUFBrLHIEEGUPpgH5CR81IGoNiOtRkNAY Hz9QsmJIYNVsg== From: Sasha Levin To: Tejun Heo Cc: Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , =?UTF-8?q?Michal=20Koutn=C3=BD?= , Shuah Khan , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] selftests: cgroup: fall back to an unlinked file without O_TMPFILE Date: Wed, 4 Nov 2026 20:18:24 -0500 Message-ID: <20261105011824.1143947-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit get_temp_fd() creates its page cache file with O_TMPFILE in the current directory. On filesystems without O_TMPFILE support, such as NFS, the open fails with EOPNOTSUPP, and with it every test that needs page cache: test_memcg_current_peak, test_memcg_min, test_memcg_low, test_memcg_high, test_memcg_max and test_memcg_reclaim. Boards that boot with an NFS root fail all six. Create a regular file with mkstemp() and unlink it in that case. Fixes: 84092dbcf901 ("selftests: cgroup: add memory controller self-tests") Signed-off-by: Sasha Levin --- Found with KernelCI's NVIDIA lab, whose boards boot from NFS. Tested on a 144-CPU Grace with KernelCI's arm64 build of 05441d697f7f9: run from an NFSv3 mount, all six tests fail without this patch. With it, they behave as they do from ext4 on that machine: the other four pass, while test_memcg_min fails and test_memcg_low sometimes fails there too. tools/testing/selftests/cgroup/test_memcontrol.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/cgroup/test_memcontrol.c b/tools/testing/selftests/cgroup/test_memcontrol.c index bb673012dcf08..7dc9c26628675 100644 --- a/tools/testing/selftests/cgroup/test_memcontrol.c +++ b/tools/testing/selftests/cgroup/test_memcontrol.c @@ -33,7 +33,17 @@ static int page_size; int get_temp_fd(void) { - return open(".", O_TMPFILE | O_RDWR | O_EXCL, 0600); + char name[] = "./cgroup_test_XXXXXX"; + int fd; + + fd = open(".", O_TMPFILE | O_RDWR | O_EXCL, 0600); + if (fd >= 0 || errno != EOPNOTSUPP) + return fd; + + fd = mkstemp(name); + if (fd >= 0) + unlink(name); + return fd; } int alloc_pagecache(int fd, size_t size) -- 2.53.0