From patchwork Mon Feb 1 08:56:23 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 12058503 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 31D38C433E0 for ; Mon, 1 Feb 2021 08:58:20 +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 C39F864E33 for ; Mon, 1 Feb 2021 08:58:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C39F864E33 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 928C56E52F; Mon, 1 Feb 2021 08:57:45 +0000 (UTC) Received: from fireflyinternet.com (unknown [77.68.26.236]) by gabe.freedesktop.org (Postfix) with ESMTPS id 685A16E4F8 for ; Mon, 1 Feb 2021 08:57:36 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from build.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 23757718-1500050 for multiple; Mon, 01 Feb 2021 08:57:16 +0000 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Mon, 1 Feb 2021 08:56:23 +0000 Message-Id: <20210201085715.27435-5-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210201085715.27435-1-chris@chris-wilson.co.uk> References: <20210201085715.27435-1-chris@chris-wilson.co.uk> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 05/57] drm/i915: Take rcu_read_lock for querying fence's driver/timeline names 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: , Cc: Chris Wilson Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" The name very often may be freed independently of the fence, with the only protection being RCU. To be safe as we read the names, hold RCU. Signed-off-by: Chris Wilson Reviewed-by: Mika Kuoppala --- drivers/gpu/drm/i915/i915_sw_fence.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_sw_fence.c b/drivers/gpu/drm/i915/i915_sw_fence.c index 2744558f3050..dfabf291e5cd 100644 --- a/drivers/gpu/drm/i915/i915_sw_fence.c +++ b/drivers/gpu/drm/i915/i915_sw_fence.c @@ -430,11 +430,13 @@ static void timer_i915_sw_fence_wake(struct timer_list *t) if (!fence) return; + rcu_read_lock(); pr_notice("Asynchronous wait on fence %s:%s:%llx timed out (hint:%ps)\n", cb->dma->ops->get_driver_name(cb->dma), cb->dma->ops->get_timeline_name(cb->dma), cb->dma->seqno, i915_sw_fence_debug_hint(fence)); + rcu_read_unlock(); i915_sw_fence_set_error_once(fence, -ETIMEDOUT); i915_sw_fence_complete(fence);