From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753901AbbALSGt (ORCPT ); Mon, 12 Jan 2015 13:06:49 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:57776 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752453AbbALSGq (ORCPT ); Mon, 12 Jan 2015 13:06:46 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Chris Wilson , Paulo Zanoni , Imre Deak , Daniel Vetter , Luis Henriques Subject: [PATCH 3.16.y-ckt 074/216] drm/i915: Only warn the first time we attempt to mmio whilst suspended Date: Mon, 12 Jan 2015 18:03:11 +0000 Message-Id: <1421085933-32536-75-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1421085933-32536-1-git-send-email-luis.henriques@canonical.com> References: <1421085933-32536-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt4 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Chris Wilson commit 2b387059817fd100cddc5a97118d63e3f3fade74 upstream. In all likelihood we will do a few hundred errnoneous register operations if we do a single invalid register access whilst the device is suspended. As each instance causes a WARN, this floods the system logs and can make the system unresponsive. The warning was first introduced in commit b2ec142cb0101f298f8e091c7d75b1ec5b809b65 Author: Paulo Zanoni Date: Fri Feb 21 13:52:25 2014 -0300 drm/i915: call assert_device_not_suspended at gen6_force_wake_work and despite the claims the WARN is still encountered in the wild today. Signed-off-by: Chris Wilson Cc: Paulo Zanoni Cc: Imre Deak Signed-off-by: Daniel Vetter Signed-off-by: Luis Henriques --- drivers/gpu/drm/i915/intel_uncore.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c index 4f6fef7ac069..28ac6156ec1d 100644 --- a/drivers/gpu/drm/i915/intel_uncore.c +++ b/drivers/gpu/drm/i915/intel_uncore.c @@ -43,8 +43,8 @@ static void assert_device_not_suspended(struct drm_i915_private *dev_priv) { - WARN(HAS_RUNTIME_PM(dev_priv->dev) && dev_priv->pm.suspended, - "Device suspended\n"); + WARN_ONCE(HAS_RUNTIME_PM(dev_priv->dev) && dev_priv->pm.suspended, + "Device suspended\n"); } static void __gen6_gt_wait_for_thread_c0(struct drm_i915_private *dev_priv) -- 2.1.4