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 127A8CD37B6 for ; Mon, 11 May 2026 03:11:39 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 396376B0088; Sun, 10 May 2026 23:11:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 346F26B008A; Sun, 10 May 2026 23:11:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 283116B008C; Sun, 10 May 2026 23:11:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 176946B0088 for ; Sun, 10 May 2026 23:11:39 -0400 (EDT) Received: from smtpin17.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay03.hostedemail.com (Postfix) with ESMTP id AC595A0553 for ; Mon, 11 May 2026 03:11:38 +0000 (UTC) X-FDA: 84753663876.17.BE1B611 Received: from out-173.mta1.migadu.com (out-173.mta1.migadu.com [95.215.58.173]) by imf18.hostedemail.com (Postfix) with ESMTP id C55F41C0007 for ; Mon, 11 May 2026 03:11:36 +0000 (UTC) Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=tw0aVY8a; spf=pass (imf18.hostedemail.com: domain of lance.yang@linux.dev designates 95.215.58.173 as permitted sender) smtp.mailfrom=lance.yang@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=1778469097; 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=cL0FELGoVYHYTfhfL2RHbUuOhJzysi3xHVnV5drpBKA=; b=3zqs4Y2y6UQs47jiCWbkFd/pr4iIJ+3rwl4S2i6OUl/3rqcAoZjzavN8GZlIQLQTBD5hPM 1EpGy32fXwW9KPj3on0cq3JlyQH3leLuOcUYC08gwQV9EDRMW8Q4dEEsDUugR+tTX1jmX4 v4Q6zU8hqemEkUX6SRZ7oAP5O2mKmek= ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=tw0aVY8a; spf=pass (imf18.hostedemail.com: domain of lance.yang@linux.dev designates 95.215.58.173 as permitted sender) smtp.mailfrom=lance.yang@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1778469097; a=rsa-sha256; cv=none; b=wYuKqKyYZNAqUK6C66PTXOSAONhIQMJbqvnVbTu7vM6GLHbGfDcpbWwuOMYQcR6n8XTvTP rpHMZqt2Mq3CljbASv+DBX+sMbZGKmCTmosI46QQm3sUhraUrr5tF27z5ZzEqK+nVBO3NZ fTR7GB834h2X7Dw15CP3On44ySzEEL0= Message-ID: <49787989-f05f-4e2c-bbad-bd8fa0e19dff@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1778469094; 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=cL0FELGoVYHYTfhfL2RHbUuOhJzysi3xHVnV5drpBKA=; b=tw0aVY8ay56GlUCDSCSYyOfeV/6Vr4TLp7y6hN9kIzYmg6dA3V/AjJnAKwjAXaHRciTwhp iiOup3nQKXgLjTE9CITs1ZorXI/i5bfzIuBJWNa3SSPT0VJfwJjcL4VULO1Nde1Ac1ykrP j6QidKjpP7t2u7k5sPCL+kYb8LLuhhE= Date: Mon, 11 May 2026 11:11:16 +0800 MIME-Version: 1.0 Subject: Re: [PATCH v3] mm/khugepaged: fix inconsistent MMF_VM_HUGEPAGE flag due to allocation failure order To: Ye Liu Cc: Ye Liu , Zi Yan , Baolin Wang , "Liam R. Howlett" , Nico Pache , Xin Hao , Lorenzo Stoakes , David Hildenbrand , Ryan Roberts , Dev Jain , Barry Song , Andrew Morton , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260511025408.54035-1-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: Lance Yang In-Reply-To: <20260511025408.54035-1-ye.liu@linux.dev> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-Rspam-User: X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: C55F41C0007 X-Stat-Signature: wchn7pq3guweonwhjipng3iu5ipmeiz6 X-HE-Tag: 1778469096-1033 X-HE-Meta: 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 bHSTmYi0 o/XdSWTEShkrOBWvqGEb5RU9SQ+JI3PKHUZqTj4RMVIcEgrgxu0/DJcsB+3aTKGWn11rGeFlQaYeInHa1K/NTQNCaCobKKvMl8e6tkUaE+jtiADq/NXJ4dbsnqFn7UKTw/790HozWzdKRkJv5elr8hJKYwxI+In0JL8WSCLK4CPoCrlb3Mc2rCBcdSg8gP7tKpZFcId+FeGhpLzc2WA5+3F+4jpOke7drDWeT/R5DbU/Mhd/HgCw6Xemv3LjWN+Bu/1MjqL96lDmhRfst0Yqjh9QuyAxy3qXgaO63pct9UsrwkIoOnz59Qv4TCkCmmci2CnDFkOOfD7eAOQdeflyHnEg6wg== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2026/5/11 10:54, Ye Liu wrote: > From: Ye Liu > > __khugepaged_enter() sets MMF_VM_HUGEPAGE before allocating the > corresponding mm_slot. If mm_slot_alloc() fails, the function > returns with the flag set but without inserting the mm into the > khugepaged tracking structures, leaving the mm in an inconsistent > state where future registration attempts are skipped. > > Fix this by reordering: allocate the mm_slot first, then check and > set the flag. If the flag is already set, free the allocated slot > and return. This ensures the flag is only set when the mm is > successfully registered in the khugepaged tracking structures. > > Fixes: 16618670276a ("mm: khugepaged: avoid pointless allocation for "struct mm_slot"") > Suggested-by: David Hildenbrand > Signed-off-by: Ye Liu > --- LGTM, thanks. Reviewed-by: Lance Yang