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 BD6E8F327CD for ; Tue, 21 Apr 2026 09:26:04 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 10D0C6B0088; Tue, 21 Apr 2026 05:26:04 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 094866B0089; Tue, 21 Apr 2026 05:26:04 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EC5296B008A; Tue, 21 Apr 2026 05:26:03 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id D8A2B6B0088 for ; Tue, 21 Apr 2026 05:26:03 -0400 (EDT) Received: from smtpin30.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 1689D13C220 for ; Tue, 21 Apr 2026 09:26:03 +0000 (UTC) X-FDA: 84682031406.30.A62A7D9 Received: from out-187.mta1.migadu.com (out-187.mta1.migadu.com [95.215.58.187]) by imf05.hostedemail.com (Postfix) with ESMTP id 0EA9B10000A for ; Tue, 21 Apr 2026 09:26:00 +0000 (UTC) Authentication-Results: imf05.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=SD3D3SKU; spf=pass (imf05.hostedemail.com: domain of ye.liu@linux.dev designates 95.215.58.187 as permitted sender) smtp.mailfrom=ye.liu@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1776763561; 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=NzaoaMrVPuNqytuMUronCSujODBOvvcOBPL0ZtXO8I8=; b=VfUigwTMlBfsT0Qw8+FjCqI1GWtUPQo+ku2zFdzhAvhzZGTsprbtgHNv7GJRRNXeQyZtsv tb9BRZH95ObtthlotUaHOC9LaP9owGZH+iNYugnYynPvZyAv2ezf9esdxjwFMbhP7OXgLQ MdFPBwRFhF5JegvFEOb8yAlA8ZbX8do= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1776763561; a=rsa-sha256; cv=none; b=OIwHnQRwWnxff8PjApUJSbJjq+n7/ofuPSmE2ey1DHhqvC19L6XyRsSBn8zeV2FAhmOeqH rnVpxeIF70Z8Htln1ao5UJ/DDzG+6Bmt4mGQBW/1NGZgDDQWFd4dptMPCKYTtVPrs35Lo4 xbqAtsSAuJJqrGFBKScbvHorEct/eq4= ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=SD3D3SKU; spf=pass (imf05.hostedemail.com: domain of ye.liu@linux.dev designates 95.215.58.187 as permitted sender) smtp.mailfrom=ye.liu@linux.dev; dmarc=pass (policy=none) header.from=linux.dev Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1776763558; 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: in-reply-to:in-reply-to:references:references; bh=NzaoaMrVPuNqytuMUronCSujODBOvvcOBPL0ZtXO8I8=; b=SD3D3SKUPgIj+qrhNP8UR11PcWh6kw6SdyuhxhuNn0ebQLCWAqlwY98c9XHwiFysnJ8hWq 45aWzk4gKq8Ql94lOUphOrMTtyvXqtK2qVDockgcF0MR/1VbwRPFuk6BFp4vpbW6rtbCme YA/THdxoYQ0wBEvAdX2zDNi8oZWR6cA= Date: Tue, 21 Apr 2026 17:25:38 +0800 MIME-Version: 1.0 Subject: Re: [PATCH] mm: handle potential NULL return from anon_vma_name_reuse() To: Lorenzo Stoakes , David Hildenbrand Cc: Andrew Morton , "Liam R. Howlett" , Ye Liu , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Kairui Song , Qi Zheng , Shakeel Butt , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Jann Horn , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260421085056.26033-1-ye.liu@linux.dev> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Ye Liu In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Stat-Signature: k571trx5sx915wibtauic1cqbript6pb X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 0EA9B10000A X-Rspam-User: X-HE-Tag: 1776763560-719801 X-HE-Meta: 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 xmQ4RDBP 1uz+rSMERwUch2VP1R6VdCJkznu8whDRrjKXwEMcQXT3NIpDvz6f8hKZig48e4dL1ZG4hEL705XjJUoMBfKo4/aV0jFcgxwW5LoxlFbaVLYVxj6DN8LJXH3cOe5Ch0LNaDEhEzXkYr2Clp5VAmockJNzA4m3XBROU4Ps/Z6EhnPiqEZleDZeUfzahsCzy/LBQSlKocopo3gso7p39XMKwClSxEkcY4ZrTalyRf7wACYXDoxF/SblCi+C5Oa6v2YMBmA4fDI5edGuFD3zfzN3DXyfsGw== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: 在 2026/4/21 17:08, Lorenzo Stoakes 写道: > NAK, expected allocation failures (even if practically impossible) should not > cause arbitrary kernel warnings. Thank you both for the thorough review and explanation. You are absolutely right. I mistakenly assumed that leaving vma->anon_name as NULL could lead to a NULL pointer dereference in some path, but as you pointed out, the code is designed to treat NULL as "no name", which is perfectly valid. I also acknowledge that adding a WARN_ON_ONCE in an allocation failure path is incorrect and harmful under memory pressure. Please disregard this patch. I've learned a valuable lesson about error handling in cosmetic features. Thank you again for the guidance. -- Thanks, Ye Liu