From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3EB18CA5FD2 for ; Thu, 1 Oct 2026 21:18:16 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E704B6B008C; Thu, 1 Oct 2026 17:18:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id DF97D6B0092; Thu, 1 Oct 2026 17:18:14 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CE80F6B0093; Thu, 1 Oct 2026 17:18:14 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 907606B008C for ; Thu, 1 Oct 2026 17:18:14 -0400 (EDT) Received: from smtpin27.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 0CD031C302C for ; Thu, 1 Oct 2026 21:18:14 +0000 (UTC) X-FDA: 85275320508.27.CC37189 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf03.hostedemail.com (Postfix) with ESMTP id CF3222000F for ; Thu, 1 Oct 2026 21:18:11 +0000 (UTC) Authentication-Results: imf03.hostedemail.com; dkim=pass header.d=arm.com header.s=foss header.b=KuEUnD1L; spf=pass (imf03.hostedemail.com: domain of yeoreum.yun@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=yeoreum.yun@arm.com; dmarc=pass (policy=none) header.from=arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1790889492; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=L4au1uvSYz6hPzXJBCWZKPqrcb7mlvjmhpIZyOfli+U=; b=dmsYbE0x4Tp+7yW2zURlrIBN0l1G+vGoDBRjO3QM5qN/1jrg1BzuM02cq1bQebuRfOBbNd 5Yyjrdg2YZRy5w79Q0cMUUbIUrC2DL2NoJZmDK8pJdR6DqBTr1OFPb/fhYC5+VH0HFRorb olRf2JYVptOdxCf5H3vtyFUfBiFv6W4= ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1790889492; b=N0LHZagVa2GrE/EOFnpDXX22PFS/OxnZczPb3XTqs8vRsWTfskNPY0UAAqyFken48gbzPk X3kqFgwUJmTpOHo3lToCYxHjCNC2Yk7TkxvsReNqScnNlExNFHzxwmvbIZbWTZ531jLbSM hCQQDxIVDAL8XG5wFPrN8/N6LrDs/U8= ARC-Authentication-Results: i=1; imf03.hostedemail.com; dkim=pass header.d=arm.com header.s=foss header.b=KuEUnD1L; spf=pass (imf03.hostedemail.com: domain of yeoreum.yun@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=yeoreum.yun@arm.com; dmarc=pass (policy=none) header.from=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 797821476; Thu, 1 Oct 2026 14:18:06 -0700 (PDT) Received: from e129823.arm.com (e129823.arm.com [10.2.213.3]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E38223F86F; Thu, 1 Oct 2026 14:18:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1790889489; bh=QTDzI9TFR5poyDcHbXwN5yB0vq+wEkyrdEszsBvl/zE=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=KuEUnD1LIbrX/jzzm1mZU/5F3Ih+d9xB1/92+Mz5bXrOPOgmJGXD68Xo+HU4T+sjf uUJU6JOq70hPW4Su+HLIYp5N+9TfL8d/JnhxGV8zCiyqzp4bxpqN5IGQS4LtYIuAmn 7L/Vp08sWJtgtf1TkHBorBCIGw/zajASP6GMTtmY= From: Yeoreum Yun Date: Thu, 01 Oct 2026 22:17:51 +0100 Subject: [PATCH v9 1/4] kselftest: mm: prevent random failure of huge page split for khugepaged MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20261001-fix_split-v9-1-0f4ba8bbdbdf@arm.com> References: <20261001-fix_split-v9-0-0f4ba8bbdbdf@arm.com> In-Reply-To: <20261001-fix_split-v9-0-0f4ba8bbdbdf@arm.com> To: Andrew Morton , David Hildenbrand , Lorenzo Stoakes , Zi Yan , Baolin Wang , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Shuah Khan , Kevin Brodsky Cc: linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Sarthak Sharma , Yeoreum Yun X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2774; i=yeoreum.yun@arm.com; h=from:subject:message-id; bh=QTDzI9TFR5poyDcHbXwN5yB0vq+wEkyrdEszsBvl/zE=; b=owEB7QES/pANAwAKAW3Vw9FaxTEzAcsmYgBqvs4JqSJ1v+3SCIVc/Qop0U3V/fHOG0In9DYc6 qk+W9AnCi2JAbMEAAEKAB0WIQQtg+CS3QUzuFh1pJ1t1cPRWsUxMwUCar7OCQAKCRBt1cPRWsUx M3GrDADMQ9d4L9YVcXONl31+8k2UAQroC+yDBfRk+kHoqTncqw/AFZd7JktlL4pZNsOiLhl9MB2 hjUqOHiPzndcOKMiKCugRHmoiZ21xvIi6JpbXGzNWuOV4KTKl5Zgti4LXttMFTpdKDYMK5FUhZe fNyFE5cpSyny5d8rKJk/C2KbwvnYGZvijDOzpHkidAbG75XD8fKx+TQPyA79E3on2eAYmbPw7cE QR9lMSNFU7tuau5RgRmRi6N256cX1Fm8S5D4gIvcD8tikyGWY76r0/EEstl12wedqXytcHQpCBD ThZt2haAqv9Gt0IiEfCNJgHrzDtxfjrjw3KCHs2aQF93T9M3Lq3QKdvq1+1GJ5nKrzuTf8hof7l VFd3Fop4Eef5hmAd5aa6Af9XUJpvc2p1aVH8aP3ZjdvefZsyUjt4GUeXLSPo74mCTn92X2cemAX a6NWDcoLLOaJS8FPkHShJtN0GUSFQKiKAY+gwmyp2QuuGBVDTh/Urk7XRGZY9jZUo+eRE= X-Developer-Key: i=yeoreum.yun@arm.com; a=openpgp; fpr=2D83E092DD0533B85875A49D6DD5C3D15AC53133 X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: CF3222000F X-Stat-Signature: d1n89jfo3jm9yh67xcatqomioiy9jtz1 X-Rspam-User: X-HE-Tag: 1790889491-231482 X-HE-Meta: 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 6VEbzpTP KAzG9SDEQy4H+0AYJg1fS8HQFsQe/kfxkJW2oMZb0q36li3C6DY0swrLKZrCZs8k11TvebFdetlpWGWEKFAWEUdMpZw77vAlPHi/5CiyNeDHDYgW3nW92sHMw/dUI/NpkZbF0aLTAsMA4GGgC46R+3ynWuG92P7UVMVX/Qw6IMZckxCyD3VGkam/CwgC9HUtVzmpjmOQfq+ZL/bwfkfbHhOCmrY2EmugXmobxwCYf7sW/GgGqwRqQZ7LF1jSiOIWDhMcqIxpMybm0bzL2jJery0dDeG2erIv/PMjmJx+SViS/hsM= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: There're some random failure for split_huge_page_test when khugepaged collapses pages into pmd again which had split by the test. Prevent the khugepaged's collapses for split page by setting the mapped pmd-huge-page with MADV_NOHUGEPAGE before split. Suggested-by: Kevin Brodsky Suggested-by: Lorenzo Stoakes (ARM) Reviewed-by: Lorenzo Stoakes (ARM) Reviewed-by: Zi Yan Reviewed-by: Sarthak Sharma Acked-by: David Hildenbrand (Arm) Signed-off-by: Yeoreum Yun --- tools/testing/selftests/mm/split_huge_page_test.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/tools/testing/selftests/mm/split_huge_page_test.c b/tools/testing/selftests/mm/split_huge_page_test.c index c5d96a4b1db3..36a6719ff09a 100644 --- a/tools/testing/selftests/mm/split_huge_page_test.c +++ b/tools/testing/selftests/mm/split_huge_page_test.c @@ -108,6 +108,15 @@ static char *allocate_zero_filled_hugepage(size_t len) return result; } +static void disable_khugepaged(void *addr, size_t len) +{ + /* Disables khugepaged from collapsing pages in range into THPs */ + if (!madvise(addr, len, MADV_NOHUGEPAGE)) + return; + + ksft_exit_fail_perror("MADV_NOHUGEPAGE failed"); +} + static void verify_rss_anon_split_huge_page_all_zeroes(char *one_page, int nr_hpages, size_t len) { unsigned long rss_anon_before, rss_anon_after; @@ -120,6 +129,8 @@ static void verify_rss_anon_split_huge_page_all_zeroes(char *one_page, int nr_hp if (!rss_anon_before) ksft_exit_fail_msg("No RssAnon is allocated before split\n"); + disable_khugepaged(one_page, len); + /* split all THPs */ write_debugfs(PID_FMT, getpid(), (uint64_t)one_page, (uint64_t)one_page + len, 0); @@ -167,6 +178,8 @@ static void split_pmd_thp_to_order(int order) if (!check_huge_anon(one_page, 4 * pmd_pagesize, 4, pmd_pagesize)) ksft_exit_fail_msg("No THP is allocated\n"); + disable_khugepaged(one_page, len); + /* split all THPs */ write_debugfs(PID_FMT, getpid(), (uint64_t)one_page, (uint64_t)one_page + len, order); @@ -215,6 +228,8 @@ static void split_pte_mapped_thp(void) goto out; } + disable_khugepaged(thp_area, thp_area_size); + /* * To challenge spitting code, we will mremap a single page of each * THP (page[i] of thp[i]) in the thp_area into page_area. This will @@ -482,6 +497,7 @@ static int create_pagecache_thp_and_fd(const char *testfile, size_t fd_size, ksft_test_result_skip("Pagecache folio split skipped\n"); return -2; } + disable_khugepaged(*addr, fd_size); return 0; err_out_close: close(*fd); -- 2.43.0