From patchwork Tue Dec 10 15:36:20 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 11282831 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 15971112B for ; Tue, 10 Dec 2019 15:36:43 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F15A72077B for ; Tue, 10 Dec 2019 15:36:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F15A72077B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=chris-wilson.co.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B70A46E124; Tue, 10 Dec 2019 15:36:41 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id CFE1C6E12C for ; Tue, 10 Dec 2019 15:36:39 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from haswell.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 19528874-1500050 for multiple; Tue, 10 Dec 2019 15:36:20 +0000 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Tue, 10 Dec 2019 15:36:20 +0000 Message-Id: <20191210153620.3929372-1-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.24.0 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH] drm/i915/gt: Check we are the Ironlake IPS provider before deregistering X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Check that we own the global pointer before deregistering. Reported-by: Venkata Sandeep Dhanalakota Signed-off-by: Chris Wilson Cc: Venkata Sandeep Dhanalakota Cc: Andi Shyti Reviewed-by: Venkata Sandeep Dhanalakota --- drivers/gpu/drm/i915/gt/intel_rps.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/gt/intel_rps.c b/drivers/gpu/drm/i915/gt/intel_rps.c index 08a38a3b90b0..fd01e4100fc1 100644 --- a/drivers/gpu/drm/i915/gt/intel_rps.c +++ b/drivers/gpu/drm/i915/gt/intel_rps.c @@ -1715,6 +1715,7 @@ void intel_rps_driver_register(struct intel_rps *rps) * set up, to avoid intel-ips sneaking in and reading bogus values. */ if (IS_GEN(gt->i915, 5)) { + GEM_BUG_ON(ips_mchdev); rcu_assign_pointer(ips_mchdev, gt->i915); ips_ping_for_i915_load(); } @@ -1722,7 +1723,8 @@ void intel_rps_driver_register(struct intel_rps *rps) void intel_rps_driver_unregister(struct intel_rps *rps) { - rcu_assign_pointer(ips_mchdev, NULL); + if (ips_mchdev == rps_to_i915(rps)) + rcu_assign_pointer(ips_mchdev, NULL); } static struct drm_i915_private *mchdev_get(void)