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[147.75.80.249]) by mx.google.com with ESMTPS id e5-20020a170906314500b00a46f99d910esi4620593eje.634.2024.03.27.07.10.09 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 27 Mar 2024 07:10:09 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel+bounces-121285-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) client-ip=147.75.80.249; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=casper.20170209 header.b=cJsQBQlG; arc=pass (i=1 dkim=pass dkdomain=infradead.org); spf=pass (google.com: domain of linux-kernel+bounces-121285-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) smtp.mailfrom="linux-kernel+bounces-121285-linux.lists.archive=gmail.com@vger.kernel.org" Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by am.mirrors.kernel.org (Postfix) with ESMTPS id 055251F2C4A9 for ; Wed, 27 Mar 2024 14:09:51 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id A2D9F12F38D; Wed, 27 Mar 2024 12:32:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="cJsQBQlG" Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2A0C412EBC8 for ; Wed, 27 Mar 2024 12:32:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711542771; cv=none; b=TvOUuuwod81dD+xQtA/ObADKj/VCzYXIxXpY9JByrI/AUXb8bQj6zfJuSR1Ax/9Ds38vOX1Oi2wAU6oEruRWDz4yeULN+m/84ecI9v9KwjS8i7aRrR0ZFOBfyDG2USQsfO+MvYf7353cPrN9jR1r6nXc+gpfvUZxjFOqijau5lg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711542771; c=relaxed/simple; bh=a4o0A6ggKfF3YJK9T/cm1DSZSsKsJAOhYfrZh8H57PE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=F9qhGj5uQc/7g1qWp/2ZEb69/xK50fkwJ6Bwph1YvY7TVHD0xBGGKfCwLqeLbhEWF77Th1fvav9UVWAjahmVHRUBkztPJyXPYCTc0E6lehAX78jmUdna209fLZjuuQuuYpS7zlggbTTgsjq0aWpjcfL9DefQOB1BU7cFfX9xy3c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=cJsQBQlG; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=l6GZOMZ+j81OaJ382d3JAd6zvAL+ZqNG19CFuQDVLPk=; b=cJsQBQlGZHSZtJpD0rZeloENVv 4Hten8gDfDu3gEft+8N6tNJ5XuKV3Ex997I4AurtmJAKCZVUCm3oQa6QfB72EeJF1x5jme03dsQIW Df3Y0lBQLaHO2NC//OVnBby6yqo9jRXd00mNR62yqV8898L/1HvQpDXqMaPInBwmrz6XmoMM5OxmZ ac9wwPYAjc2bSJ14DmRRdk6ACRqUUsiM6G8VgUHbW3j80YWP72v8Vo9L/1lc4H+W3gJpjJNfKfmKj e4+dKXmLPCykxbfZE0f2Uy6nVrbGDz3c992MNYsnE/apqBjGf2aLBoisVAiwGvKraufV3fTI27ODb xptM7/hA==; Received: from willy by casper.infradead.org with local (Exim 4.97.1 #2 (Red Hat Linux)) id 1rpSSV-00000003qbf-1PIW; Wed, 27 Mar 2024 12:32:47 +0000 Date: Wed, 27 Mar 2024 12:32:47 +0000 From: Matthew Wilcox To: "zhaoyang.huang" Cc: Andrew Morton , Christoph Hellwig , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Zhaoyang Huang , steve.kang@unisoc.com Subject: Re: [PATCH] mm: fix unproperly folio_put by changing API in read_pages Message-ID: References: <20240327055406.1339636-1-zhaoyang.huang@unisoc.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240327055406.1339636-1-zhaoyang.huang@unisoc.com> On Wed, Mar 27, 2024 at 01:54:06PM +0800, zhaoyang.huang wrote: > From: Zhaoyang Huang > > According to the comments of readahead_page[3], the refcnt which > represents page cache dropped in [1] makes sense for two reasons, '1. > The folio is going to do IO and is locked until IO done;2. The refcnt > will be added back when found again from the page cache and then serve > for PTE or vfs' while it doesn't make sense in [2] as the refcnt of > page cache will be dropped in filemap_remove_folio. NAK, per previous email.