From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752220AbeFERDF (ORCPT ); Tue, 5 Jun 2018 13:03:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:59912 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751902AbeFERDC (ORCPT ); Tue, 5 Jun 2018 13:03:02 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Arnd Bergmann , "David S. Miller" , Guenter Roeck Subject: [PATCH 4.4 13/37] irda: fix overly long udelay() Date: Tue, 5 Jun 2018 19:01:18 +0200 Message-Id: <20180605170109.686137201@linuxfoundation.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180605170108.884872354@linuxfoundation.org> References: <20180605170108.884872354@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Arnd Bergmann commit c9bd28233b6d0d82ac3ba0215723be0a8262c39c upstream. irda_get_mtt() returns a hardcoded '10000' in some cases, and with gcc-7, we get a build error because this triggers a compile-time check in udelay(): drivers/net/irda/w83977af_ir.o: In function `w83977af_hard_xmit': w83977af_ir.c:(.text.w83977af_hard_xmit+0x14c): undefined reference to `__bad_udelay' Older compilers did not run into this because they either did not completely inline the irda_get_mtt() or did not consider the 10000 value a constant expression. The code has been wrong since the start of git history. Signed-off-by: Arnd Bergmann Signed-off-by: David S. Miller Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman --- drivers/net/irda/w83977af_ir.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/net/irda/w83977af_ir.c +++ b/drivers/net/irda/w83977af_ir.c @@ -518,7 +518,9 @@ static netdev_tx_t w83977af_hard_xmit(st mtt = irda_get_mtt(skb); pr_debug("%s(%ld), mtt=%d\n", __func__ , jiffies, mtt); - if (mtt) + if (mtt > 1000) + mdelay(mtt/1000); + else if (mtt) udelay(mtt); /* Enable DMA interrupt */