From patchwork Sun Mar 30 12:02:04 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ignacio Encinas X-Patchwork-Id: 14032899 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 F41C2C28B20 for ; Sun, 30 Mar 2025 12:03:15 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5D807280002; Sun, 30 Mar 2025 08:03:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 55CD1280001; Sun, 30 Mar 2025 08:03:14 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3FDD5280002; Sun, 30 Mar 2025 08:03:14 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 1B22B280001 for ; Sun, 30 Mar 2025 08:03:14 -0400 (EDT) Received: from smtpin05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 5AD791210A6 for ; Sun, 30 Mar 2025 12:03:14 +0000 (UTC) X-FDA: 83278081908.05.AF09231 Received: from out-174.mta1.migadu.com (out-174.mta1.migadu.com [95.215.58.174]) by imf04.hostedemail.com (Postfix) with ESMTP id 69E0140012 for ; Sun, 30 Mar 2025 12:03:12 +0000 (UTC) Authentication-Results: imf04.hostedemail.com; dkim=pass header.d=iencinas.com header.s=key1 header.b=Z8X9AgPC; spf=pass (imf04.hostedemail.com: domain of ignacio@iencinas.com designates 95.215.58.174 as permitted sender) smtp.mailfrom=ignacio@iencinas.com; dmarc=pass (policy=quarantine) header.from=iencinas.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1743336192; 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: references:dkim-signature; bh=qfO5eTwwoRJBvkdNLyv0KkdLxqFech3hJfLffpWq3Pg=; b=kZuhHMpBKGZluaywNnSv18mqty/7Qf+E8bKbFq9TAQYu1rM6Pn++ICiBTU+EC5Y/VLd4fQ GgMFGu942GNuGQNLAHlC+u9vtsx0fCbGv6qD5izi3CkOolawV4xh14fSP6AX6V8wlgWoEk YuiTUDgMF27VyucyUtY0Me8AccwhKp0= ARC-Authentication-Results: i=1; imf04.hostedemail.com; dkim=pass header.d=iencinas.com header.s=key1 header.b=Z8X9AgPC; spf=pass (imf04.hostedemail.com: domain of ignacio@iencinas.com designates 95.215.58.174 as permitted sender) smtp.mailfrom=ignacio@iencinas.com; dmarc=pass (policy=quarantine) header.from=iencinas.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1743336192; a=rsa-sha256; cv=none; b=YDZSR1mQYtG6t7GqAsgaPpyAVUnRObzNqL0guSOH+V0Y+o8j9vtZtW5cLnw3mX2VSDiN8j 3NkFiySDilAWnyO8YMl+rCEAJiqJsFPs2OQXpXTNGbkpri9kjhp6G1v05BqruKgFuzvSl2 j8+Q5qF1u+ZFadiqzFAsBGXMS5L34BM= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=iencinas.com; s=key1; t=1743336190; 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: content-transfer-encoding:content-transfer-encoding; bh=qfO5eTwwoRJBvkdNLyv0KkdLxqFech3hJfLffpWq3Pg=; b=Z8X9AgPCpTmz0oBNpqf8g0xuIrbfyZub85WLrv8ktCGH+Fl7pSQaJ9Dhqs9XIofMfGiXjS kV2HmIgrai8zk4ehTSx4EOm5StNEGCTh6nVPrSoeT04/WtYK3YG3KKfiFAyR8XuhTpuaBQ PBW3ivDPNPGAKMCUpG7fLkZsQ6TXTDJK/JrO3x3A/Iepx35wsm1qUZ8a0j+8v4QXq/MGNq 42xcsXMxosX1EAgvmWS4SIwewCjDvW5NbyKyHigda2gW3wvrvCJcyf0jwHVHN32RUAbxbd P1rV3XIqWoPTnp8jphB0LOO4Rs8INX2ATZ7mZvBZOZ0FdSwTHtYYDVPAeiVYyw== From: Ignacio Encinas Date: Sun, 30 Mar 2025 14:02:04 +0200 Subject: [PATCH] mm: mark mm_struct.hiwater_rss as data racy MIME-Version: 1.0 Message-Id: <20250330-mm-maxrss-data-race-v1-1-2fe0ba6b8482@iencinas.com> X-B4-Tracking: v=1; b=H4sIALsy6WcC/x3MTQqEMAxA4atI1gZa/xCvIi7SNs5kUZVERBDvP mWW3+K9B4xV2GCqHlC+xGTfCnxdQfzS9mGUVAyNa3rX+h5zxky3mmGik1ApMg6RxyG4xMF3UMp DeZX7f52X9/0B/SnasmUAAAA= X-Change-ID: 20250315-mm-maxrss-data-race-6ce86b0deb14 To: Andrew Morton Cc: linux-mm@kvack.org, Lorenzo Stoakes , "Liam R. Howlett" , linux-kernel-mentees@lists.linux.dev, skhan@linuxfoundation.org, linux-kernel@vger.kernel.org, syzbot+419c4b42acc36c420ad3@syzkaller.appspotmail.com, Ignacio Encinas X-Migadu-Flow: FLOW_OUT X-Rspamd-Queue-Id: 69E0140012 X-Rspamd-Server: rspam05 X-Rspam-User: X-Stat-Signature: s8gfbu9ncmkh3xujpbj8rde9r47hk4p6 X-HE-Tag: 1743336192-254187 X-HE-Meta: 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 sA3PK7ix 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000289, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: mm_struct.hiwater_rss can be accessed concurrently without proper synchronization as reported by KCSAN. Given that this just provides accounting information and that the extra accuracy isn't worth the potential slowdown, let's annotate is __data_racy to make KCSAN happy. Reported-by: syzbot+419c4b42acc36c420ad3@syzkaller.appspotmail.com Suggested-by: Lorenzo Stoakes Signed-off-by: Ignacio Encinas --- Similar issues have been solved in the past [1]. An actual analysis of the data race can be found in [2] and [3]. Lorenzo, I added the Suggested-by as your proposal seems roughly equivalent to what I propose. [1] https://lore.kernel.org/all/20210913105550.1569419-1-liupeng256@huawei.com/T/#u [2] https://lore.kernel.org/all/900c5035-865d-40b7-8d55-0cbbbc059294@lucifer.local/ [3] https://lore.kernel.org/linux-mm/iwtvhos74gwrk5v5szlosnkusxqp6ubqy6ytkclkucbjwdw4zr@bwxyrwcnybbz/ --- include/linux/mm_types.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- base-commit: 3571e8b091f4270d869dda7a6cc43616c6ad6897 change-id: 20250315-mm-maxrss-data-race-6ce86b0deb14 Best regards, diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 0234f14f2aa6bea42a8a62ccb915c94f556cd3cc..84c86951a978aad07ab4ecefbfff77e7418d8402 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -19,6 +19,7 @@ #include #include #include +#include #include @@ -939,7 +940,7 @@ struct mm_struct { #endif - unsigned long hiwater_rss; /* High-watermark of RSS usage */ + unsigned long __data_racy hiwater_rss; /* High-watermark of RSS usage */ unsigned long hiwater_vm; /* High-water virtual memory usage */ unsigned long total_vm; /* Total pages mapped */