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 8A088C98321 for ; Fri, 25 Sep 2026 12:38:57 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7CD446B0088; Fri, 25 Sep 2026 08:38:56 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 757606B008A; Fri, 25 Sep 2026 08:38:56 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 621D86B008C; Fri, 25 Sep 2026 08:38:56 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 3D8B26B0088 for ; Fri, 25 Sep 2026 08:38:56 -0400 (EDT) Received: from smtpin10.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay10.hostedemail.com (Postfix) with ESMTP id B4B7FC062A for ; Fri, 25 Sep 2026 12:38:55 +0000 (UTC) X-FDA: 85252239030.10.D95F0B8 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf24.hostedemail.com (Postfix) with ESMTP id D137A180008 for ; Fri, 25 Sep 2026 12:38:53 +0000 (UTC) Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=arm.com header.s=foss header.b="qD5/3Mtz"; spf=pass (imf24.hostedemail.com: domain of sarthak.sharma@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=sarthak.sharma@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=1790339934; 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=lh5V/ptxapRIR+WqaKkNIGTXXO3FUTlIWTIAMYKtU/A=; b=sEqT5gQ1SwhRhjt1lJ14GmYyU8LxBayOFTuFd+WFggI6Ahf3nLpYLS6K4LitVpZquD4MiZ zLmGA/2sMpREu0rjtJPlSg3nWzUqnaCqxEiVmzlEYStY5gHAzYMM1A65cKW2XR0NM6yASx Q+pWmLRlYus3aMOUQ4vtT2QHXmme6ds= ARC-Authentication-Results: i=1; imf24.hostedemail.com; dkim=pass header.d=arm.com header.s=foss header.b="qD5/3Mtz"; spf=pass (imf24.hostedemail.com: domain of sarthak.sharma@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=sarthak.sharma@arm.com; dmarc=pass (policy=none) header.from=arm.com ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1790339934; b=s7rzJAaxwux98QlpXzwBXrPNA9SU/tKvX88dJe4m6/m9JjIisPRxOCW5NcQPhxusP9fYCl oPnr5HmpuX5QZZr8Aj2MS1xgRGxjMSVut7yCf0nanVjOW81+TDAtmO7X7lqTIEaaqneYTD PmaxGuljWYp4+q8htNhiCP1SesfzYI8= 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 4D167169C; Fri, 25 Sep 2026 05:38:49 -0700 (PDT) Received: from [10.164.19.84] (a081061.arm.com [10.164.19.84]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3C6A63F86C; Fri, 25 Sep 2026 05:38:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1790339932; bh=3/sJDh2CYvX6ndhu9fW7GGXj1GgDR/glEJ6XbWJ6Eoc=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=qD5/3MtzVreV8Bh2VupUQ9nnBRZ5lh5KiqEmCUzeVaGdjdtAk42kWUtSv2TLHK3yx Gh8O6SM+8wgPCCeJEYjSksYixaZjd1X8spXfAjIn8kpc20AZ705kPC2zhifkAqAhx/ nXUt2bt5rOx/fCLPrpb1Y+xpq1Vieba3A9Z8bc0Y= Message-ID: Date: Fri, 25 Sep 2026 18:08:44 +0530 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v8 2/4] kselftest: mm: replace usage of /proc/self/smaps for __check_pmd_huge() To: Yeoreum Yun , 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 References: <20260924-fix_split-v8-0-cba7359d882a@arm.com> <20260924-fix_split-v8-2-cba7359d882a@arm.com> Content-Language: en-US From: Sarthak Sharma In-Reply-To: <20260924-fix_split-v8-2-cba7359d882a@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Stat-Signature: 5g7csy6raztzdtmj1r3ktdkjmca8zaky X-Rspamd-Queue-Id: D137A180008 X-Rspam-User: X-Rspamd-Server: rspam01 X-HE-Tag: 1790339933-863269 X-HE-Meta: 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 YzC8qE8d pWp4wCxgMfjGnvmavR5JFyBr1qZNwv6SvDk7CQ0zu8JDzP9kkrHx2TpchPHwB4KGwvOqRRBnzrct71I8QAoILJJuKmHmNu3Xrao4YSVz83RMAuZ6lFcToSmJQgIXK+0fBkqquh786pwYdJYSMNpVP/kv+j/uh+4OoZ8qhlgLj1nwOvA4WoOrv+fM2wbWJCY6haE5AFMK63BlJmWDJh56cmGKeKQ94WCGpTGVu18kt0zxHzCM1l5OlAUsaw8JobUq/x2vJm1m8NunGuejHpoaqdvtiRnL3CLHNPB+DcFAa7IgT2Nr1o1oWojcTNMC7lsp9aT4KzxP7zwhlxvDYpo0g1pSOvXmqahjzM4Lzd+8rnD0ywoylYLNDcjfdYiVdrD8X3x+hqzWi6hW9kfE= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 9/25/26 12:41 AM, Yeoreum Yun wrote: > Since glibc commit 321e1fc73f (“malloc: Enable 2MB THP by default on AArch64”), > glibc may call madvise(MADV_HUGEPAGE) for sufficiently large allocations > made by memalign(). > > The underlying VMA may start at a different address from the aligned > address returned by memalign(). Furthermore, a subsequent > madvise(MADV_HUGEPAGE) call does not split the VMA because the flag is > already set. > > This causes split_huge_page_test to fail because the check_pmd_huge() > helpers incorrectly require the address returned by memalign() to > match the VMA start address reported in /proc/self/smaps. > > Instead of relying on /proc/self/smaps, use /proc/self/pagemap and > /proc/kpageflags to detect huge-page mappings checking PAGE_IS_HUGE > and PAGE_IS_FILE accroding to type of huge page. s/accroding/according > > Since shmem pages are also file-backed, simply check whether the page > is file-backed. > > Fixes: 642bc52aed9 ("selftests: vm: bring common functions to a new file") Checkpatch gives a warning saying it requires atleast 12 characters of commit SHA. > Suggested-by: David Hildenbrand (Arm) > Signed-off-by: Yeoreum Yun > --- [...] > +static bool __check_pmd_huge(void *addr, size_t len, int nr_hpages, > + uint64_t hpage_size, enum check_huge_type type) > +{ > + int pagemap_fd; > + int nr_pmd_mappings = 0; > + uint64_t categories; > + char *start = addr; > + char *end = start + len; > + > + pagemap_fd = open(PAGEMAP_PATH, O_RDONLY); > + if (pagemap_fd < 0) > + ksft_exit_fail_msg("open pagemap fail\n"); Can we use ksft_exit_fail_perror("open pagemap") here? Will help in diagnosing failures as well. Apart from these nits, rest looks good. Reviewed-by: Sarthak Sharma