From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39859) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cT7Nq-0002Ko-LF for qemu-devel@nongnu.org; Mon, 16 Jan 2017 08:31:39 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cT7Nm-0001Y3-Lw for qemu-devel@nongnu.org; Mon, 16 Jan 2017 08:31:38 -0500 Received: from mail-lf0-x244.google.com ([2a00:1450:4010:c07::244]:33425) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1cT7Nm-0001Xl-F7 for qemu-devel@nongnu.org; Mon, 16 Jan 2017 08:31:34 -0500 Received: by mail-lf0-x244.google.com with SMTP id x1so7310048lff.0 for ; Mon, 16 Jan 2017 05:31:34 -0800 (PST) Sender: Paolo Bonzini References: <20170113131731.1246-1-pbonzini@redhat.com> <20170113131731.1246-7-pbonzini@redhat.com> <20170116125208.GF14226@lemon.Home> From: Paolo Bonzini Message-ID: <67f59827-f7a7-2df1-3cb9-cc066603ba59@redhat.com> Date: Mon, 16 Jan 2017 14:31:08 +0100 MIME-Version: 1.0 In-Reply-To: <20170116125208.GF14226@lemon.Home> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 06/16] nbd: do not block on partial reply header reads List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Fam Zheng Cc: qemu-devel@nongnu.org, stefanha@redhat.com On 16/01/2017 13:52, Fam Zheng wrote: > + /* Kick the read_reply_co to get the next reply. */ > + aio_co_wake(s->read_reply_co); > > Can't s->read_reply_co be NULL? nbd_read_reply_entry unsets it. (Surprisingly > this file is rather unfamiliar to me, it's possible I'm missing something.) Yes, that can happen depending on how the coroutines are scheduled when the server goes down. Paolo