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 X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A199DC54FCB for ; Thu, 23 Apr 2020 23:13:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 88C9520780 for ; Thu, 23 Apr 2020 23:13:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729387AbgDWXNG (ORCPT ); Thu, 23 Apr 2020 19:13:06 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:50064 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728501AbgDWXGv (ORCPT ); Thu, 23 Apr 2020 19:06:51 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1jRkvY-0004mo-QQ; Fri, 24 Apr 2020 00:06:40 +0100 Received: from ben by deadeye with local (Exim 4.93) (envelope-from ) id 1jRkvU-00E6vG-KR; Fri, 24 Apr 2020 00:06:36 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Jiri Kosina" , "Fabian Henneke" Date: Fri, 24 Apr 2020 00:06:36 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 169/245] hidraw: Return EPOLLOUT from hidraw_poll In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.83-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Fabian Henneke commit 378b80370aa1fe50f9c48a3ac8af3e416e73b89f upstream. Always return EPOLLOUT from hidraw_poll when a device is connected. This is safe since writes are always possible (but will always block). hidraw does not support non-blocking writes and instead always calls blocking backend functions on write requests. Hence, so far, a call to poll never returned EPOLLOUT, which confuses tools like socat. Signed-off-by: Fabian Henneke In-reply-to: Signed-off-by: Jiri Kosina [bwh: Backported to 3.16: s/EPOLL/POLL/] Signed-off-by: Ben Hutchings --- drivers/hid/hidraw.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/hid/hidraw.c +++ b/drivers/hid/hidraw.c @@ -265,7 +265,7 @@ static unsigned int hidraw_poll(struct f poll_wait(file, &list->hidraw->wait, wait); if (list->head != list->tail) - return POLLIN | POLLRDNORM; + return POLLIN | POLLRDNORM | POLLOUT; if (!list->hidraw->exist) return POLLERR | POLLHUP; return 0;