From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932721AbdJKAqa (ORCPT ); Tue, 10 Oct 2017 20:46:30 -0400 Received: from omzsmtpe03.verizonbusiness.com ([199.249.25.208]:63241 "EHLO omzsmtpe03.verizonbusiness.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932540AbdJKAq1 (ORCPT ); Tue, 10 Oct 2017 20:46:27 -0400 From: "Levin, Alexander (Sasha Levin)" X-Host: surveyor.tdc.vzwcorp.com To: "gregkh@linuxfoundation.org" CC: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Subject: [GIT PULL for-4.4 02/25] watchdog: kempld: fix gcc-4.3 build Thread-Topic: [GIT PULL for-4.4 02/25] watchdog: kempld: fix gcc-4.3 build Thread-Index: AQHTQipCdcMVp+1EF0WpDC5cNXnTwQ== Date: Wed, 11 Oct 2017 00:45:39 +0000 Message-ID: <20171011004533.8044-3-alexander.levin@verizon.com> References: <20171011004533.8044-1-alexander.levin@verizon.com> In-Reply-To: <20171011004533.8044-1-alexander.levin@verizon.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.144.60.250] Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by nfs id v9B0kaPW026529 From: Arnd Bergmann [ Upstream commit 3736d4eb6af37492aeded7fec0072dedd959c842 ] gcc-4.3 can't decide whether the constant value in kempld_prescaler[PRESCALER_21] is built-time constant or not, and gets confused by the logic in do_div(): drivers/watchdog/kempld_wdt.o: In function `kempld_wdt_set_stage_timeout': kempld_wdt.c:(.text.kempld_wdt_set_stage_timeout+0x130): undefined reference to `__aeabi_uldivmod' This adds a call to ACCESS_ONCE() to force it to not consider it to be constant, and leaves the more efficient normal case in place for modern compilers, using an #ifdef to annotate why we do this hack. Signed-off-by: Arnd Bergmann Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/watchdog/kempld_wdt.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/watchdog/kempld_wdt.c b/drivers/watchdog/kempld_wdt.c index 5bf931ce1353..978098f71761 100644 --- a/drivers/watchdog/kempld_wdt.c +++ b/drivers/watchdog/kempld_wdt.c @@ -140,12 +140,19 @@ static int kempld_wdt_set_stage_timeout(struct kempld_wdt_data *wdt_data, unsigned int timeout) { struct kempld_device_data *pld = wdt_data->pld; - u32 prescaler = kempld_prescaler[PRESCALER_21]; + u32 prescaler; u64 stage_timeout64; u32 stage_timeout; u32 remainder; u8 stage_cfg; +#if GCC_VERSION < 40400 + /* work around a bug compiling do_div() */ + prescaler = READ_ONCE(kempld_prescaler[PRESCALER_21]); +#else + prescaler = kempld_prescaler[PRESCALER_21]; +#endif + if (!stage) return -EINVAL; -- 2.11.0