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]) by smtp.lore.kernel.org (Postfix) with ESMTP id 00C93C04FFE for ; Mon, 20 May 2024 05:28:20 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id CE2E96B0082; Mon, 20 May 2024 01:28:19 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C92576B0083; Mon, 20 May 2024 01:28:19 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B81216B0085; Mon, 20 May 2024 01:28:19 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 9BAAA6B0082 for ; Mon, 20 May 2024 01:28:19 -0400 (EDT) Received: from smtpin12.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id D5877C0B52 for ; Mon, 20 May 2024 05:28:18 +0000 (UTC) X-FDA: 82137643476.12.4B1849B Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf09.hostedemail.com (Postfix) with ESMTP id C3C24140006 for ; Mon, 20 May 2024 05:28:16 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=none; spf=pass (imf09.hostedemail.com: domain of dev.jain@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=dev.jain@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=1716182897; 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; bh=6gM/vwsTnExUAhnt7VJkvcI5yziT0rLqYSZpv5r7v4I=; b=OWweBoSFNqqmW1uasPdeYjwyP/gI8u41Icwdrjf/pzkUdu2n9RWjihc1khBt4NAr3x2oCi tb0YybcXsmn9wWXeJR4P6ajQ+sy/XccXGIGAKGYgFsWU3i/3dcrk5WT8c6PNKzCqpL86yt VmpEcJVBCYOvF+QcP/k9lQhV3WEs0n8= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1716182897; a=rsa-sha256; cv=none; b=o35AfSY2w2+u4CkEGRqd8OkqB78ndm3ymAGMGNn3KYqn/5s2OkW9TqwjN9kLUcL8IIeLxa cJoAawAykQEaPwJLQXx3v4bevI5aFU7JlozG3kOWFpXI7tnHmnxajxqXdAG3VJMuBeD+Ph T73u46og7PNgCQRuQVq/1K2JQ2ys49k= ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=none; spf=pass (imf09.hostedemail.com: domain of dev.jain@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=dev.jain@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 AEF64FEC; Sun, 19 May 2024 22:28:39 -0700 (PDT) Received: from [10.162.40.20] (e116581.arm.com [10.162.40.20]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id DBE7B3F641; Sun, 19 May 2024 22:28:12 -0700 (PDT) Message-ID: <93c1392e-47c3-41e2-b6cf-c41166bdab78@arm.com> Date: Mon, 20 May 2024 10:58:05 +0530 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/2] selftests/mm: compaction_test: Fix incorrect write of zero to nr_hugepages To: Andrew Morton Cc: shuah@kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Anshuman.Khandual@arm.com, sjayaram@akamai.com, stable@vger.kernel.org References: <20240515093633.54814-1-dev.jain@arm.com> <20240515093633.54814-2-dev.jain@arm.com> <20240519170024.c2e62a7b69b00bb30e86a157@linux-foundation.org> Content-Language: en-US From: Dev Jain In-Reply-To: <20240519170024.c2e62a7b69b00bb30e86a157@linux-foundation.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Stat-Signature: 3xtfzifuupaidk3r8ngcuc8gfg7pobc3 X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: C3C24140006 X-HE-Tag: 1716182896-45898 X-HE-Meta: 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 Vj0r7iE6 gODouj9PVtTE1sQzkRJR318LP3jqBQmxYJGZxvHQyAJ1DM8NSvOcaZosdMCYE+PsF5/ttruNorHzkVwyXms79q4Ghe+3I+JiMr9iOFW6DZBz09E65NPr9WrPp9HtU0B5AsMjifPpf/cmM3v45hYVupxumBdy4BmIltgraIq+QQFWWN3K2Siwn3N0kDgxH1IXFCEdqLlYoNXENyhgtm+r5tiUoAsKZvJMJnjpruCptnLkxiR6tsrvzubf1kA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000579, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 5/20/24 05:30, Andrew Morton wrote: > On Wed, 15 May 2024 15:06:32 +0530 Dev Jain wrote: > >> nr_hugepages is not set to zero because the file offset has not been reset >> after read(). Fix that using lseek(). >> > Please fully describe the runtime effects of this bug. This is not a "bug", but a discrepancy; the following comment by the author says "Start with the initial condition of 0 huge pages", I am just ensuring that that is actually done. Although, I am not sure about the utility of doing this in the first place, since we are anyways trying to increase hugepages after that. In the second patch, I have moved away this entire logic of setting nr_hugepages to zero, to the place before we start filling up memory; if you feel that this patch is unnecessary, we may squash it.