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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A1D1CC433EF for ; Sun, 21 Nov 2021 11:02:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230237AbhKULFb (ORCPT ); Sun, 21 Nov 2021 06:05:31 -0500 Received: from mail.kernel.org ([198.145.29.99]:34352 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238036AbhKULFb (ORCPT ); Sun, 21 Nov 2021 06:05:31 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id A60C660E75; Sun, 21 Nov 2021 11:02:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637492546; bh=3WQ4Hy7C4N5e4Mvc456YSywZpMU1nWyWDKWdhSHcNnA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qnFzF2aA3uKsbVnIMdsR+RLFjNe1tXP0MbB5i1nVyhrrqjApWcsueb/B8SOzynnwY OEFmo/XVkpyCvv0aR8wZ4hzphjiT+uWsWQ8EsluTRaUuKaiOJBOomPN/3F1K74sjzx ymwiXeksCEmPM7dlaglJ9g4oai2za8L3UXKMGzqW01epFW/F3LFuJWpAOHdNASxI0l KmV1TpNCQY6tbn/QVYu4Cbfz27WIAlDPCHc2UW161w3w23MznuhnfKd6ADgVQiU17z SUZvMFRBD8WolDjiSSAjypWIJefIYIvDSaNXiGYvGEdwH/vbYrltN50AhVyPYqV4nC PflKb1MCumrmw== From: SeongJae Park To: stable@vger.kernel.org, gregkh@linuxfoundation.org Cc: akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, SeongJae Park , Linus Torvalds Subject: [PATCH for-5.15.x 1/2] mm/damon/dbgfs: use '__GFP_NOWARN' for user-specified size buffer allocation Date: Sun, 21 Nov 2021 11:02:10 +0000 Message-Id: <20211121110211.17032-2-sj@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20211121110211.17032-1-sj@kernel.org> References: <20211121110211.17032-1-sj@kernel.org> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org commit db7a347b26fe05d2e8c115bb24dfd908d0252bc3 upstream. Patch series "DAMON fixes". This patch (of 2): DAMON users can trigger below warning in '__alloc_pages()' by invoking write() to some DAMON debugfs files with arbitrarily high count argument, because DAMON debugfs interface allocates some buffers based on the user-specified 'count'. if (unlikely(order >= MAX_ORDER)) { WARN_ON_ONCE(!(gfp & __GFP_NOWARN)); return NULL; } Because the DAMON debugfs interface code checks failure of the 'kmalloc()', this commit simply suppresses the warnings by adding '__GFP_NOWARN' flag. Link: https://lkml.kernel.org/r/20211110145758.16558-1-sj@kernel.org Link: https://lkml.kernel.org/r/20211110145758.16558-2-sj@kernel.org Fixes: 4bc05954d007 ("mm/damon: implement a debugfs-based user space interface") Signed-off-by: SeongJae Park Cc: # 5.15.x Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/damon/dbgfs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index faee070977d8..2741ff79e8e8 100644 --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -32,7 +32,7 @@ static char *user_input_str(const char __user *buf, size_t count, loff_t *ppos) if (*ppos) return ERR_PTR(-EINVAL); - kbuf = kmalloc(count + 1, GFP_KERNEL); + kbuf = kmalloc(count + 1, GFP_KERNEL | __GFP_NOWARN); if (!kbuf) return ERR_PTR(-ENOMEM); @@ -247,7 +247,7 @@ static ssize_t dbgfs_kdamond_pid_read(struct file *file, char *kbuf; ssize_t len; - kbuf = kmalloc(count, GFP_KERNEL); + kbuf = kmalloc(count, GFP_KERNEL | __GFP_NOWARN); if (!kbuf) return -ENOMEM; -- 2.17.1