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 E3D60C433F5 for ; Mon, 11 Apr 2022 13:42:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346638AbiDKNpC (ORCPT ); Mon, 11 Apr 2022 09:45:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48692 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230488AbiDKNo6 (ORCPT ); Mon, 11 Apr 2022 09:44:58 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id E8F9F121 for ; Mon, 11 Apr 2022 06:42:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1649684563; 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: in-reply-to:in-reply-to:references:references; bh=SeAW1i7bP5vwPIJRU4t8M7oOEg6okFb42IgET/Pn4rE=; b=hO6FCDJjZl8ZJ/bjj9J0c6ROlrD9YudLtBNMNTyIDmbZRS1KO7EaeyJhPCY5qLvH+PQY4S 8EwvuBEWmyDEsvYPsd1GsXHfjWJRcIg2BsixezbnhCFRd4uuxXlu+BQKxGD84Ze/yy2wKo WYoz+gsfXofZ17ctJFMlgwWgH5tjqAs= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-576-1qS3aKYwOQyo5eXJq_KINw-1; Mon, 11 Apr 2022 09:42:38 -0400 X-MC-Unique: 1qS3aKYwOQyo5eXJq_KINw-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 16249811E78; Mon, 11 Apr 2022 13:42:37 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.37.45]) by smtp.corp.redhat.com (Postfix) with ESMTP id C3071492D42; Mon, 11 Apr 2022 13:42:34 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <542f749c-b0f1-1de6-cb41-26e296afb2df@linux.alibaba.com> References: <542f749c-b0f1-1de6-cb41-26e296afb2df@linux.alibaba.com> <20220406075612.60298-5-jefflexu@linux.alibaba.com> <20220406075612.60298-1-jefflexu@linux.alibaba.com> <1091405.1649680508@warthog.procyon.org.uk> To: JeffleXu Cc: dhowells@redhat.com, linux-cachefs@redhat.com, xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org, torvalds@linux-foundation.org, gregkh@linuxfoundation.org, willy@infradead.org, linux-fsdevel@vger.kernel.org, joseph.qi@linux.alibaba.com, bo.liu@linux.alibaba.com, tao.peng@linux.alibaba.com, gerry@linux.alibaba.com, eguan@linux.alibaba.com, linux-kernel@vger.kernel.org, luodaowen.backend@bytedance.com, tianzichen@kuaishou.com, fannaihao@baidu.com Subject: Re: [PATCH v8 04/20] cachefiles: notify user daemon when withdrawing cookie MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <1094492.1649684554.1@warthog.procyon.org.uk> Date: Mon, 11 Apr 2022 14:42:34 +0100 Message-ID: <1094493.1649684554@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org JeffleXu wrote: > > > >> + if (fd == 0) > >> + return -ENOENT; > > > > 0 is a valid fd. > > Yeah, but IMHO fd 0 is always for stdin? I think the allocated anon_fd > won't install at fd 0. Please correct me if I'm wrong. If someone has closed 0, then you'll get 0 next, I'm pretty sure. Try it and see. > In fact I wanna use "fd == 0" as the initial state as struct > cachefiles_object is allocated with kmem_cache_zalloc(). I would suggest presetting it to something like -2 to avoid confusion. David