From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 16063C3A5A8 for ; Wed, 4 Sep 2019 18:10:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E14D62087E for ; Wed, 4 Sep 2019 18:10:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567620639; bh=9d3XUrSeTaSLmwocDQ5m6ib+sKI74fEJgL3mfYS6ZAQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=RGmgMmdyiM0C3GB0Sb0k2bnyJSG0BS4VPWj1GliF9PsWMKIR5rx/OyrGKCT1ry1iQ YMZ5D+0km6Y3UQLtCR/owKM/Z9dPVLTpraoeiONOlqCQKX+PR1HNm/YYgVmDQ+Ak3n skL8JiqnDaTqw6jVOtivF0Ox+tbzEp0s81iN3fN0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390135AbfIDSKj (ORCPT ); Wed, 4 Sep 2019 14:10:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:54302 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390085AbfIDSKg (ORCPT ); Wed, 4 Sep 2019 14:10:36 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 88E9022CEA; Wed, 4 Sep 2019 18:10:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567620636; bh=9d3XUrSeTaSLmwocDQ5m6ib+sKI74fEJgL3mfYS6ZAQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fWAIV5m6UaUNZHtas6eX6UHxweV4ld8t9wEhGgp//oKJ/KNL5bcjW6PhuNQOhyOEc E73aeqAT5uA2uIdlfQKw7IbDjudwOq+M86jVenM1LGYW/ASjCDmqO5xAxduxulCjRY V69l8qt5/qDZTXTbHM+OqmKjVTyM/iJ0AM9k6/PE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Christian=20K=C3=B6nig?= , Andrey Grodzovsky , Monk.liu@amd.com, Alex Deucher , Sasha Levin Subject: [PATCH 5.2 038/143] drm/scheduler: use job count instead of peek Date: Wed, 4 Sep 2019 19:53:01 +0200 Message-Id: <20190904175315.541114767@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190904175314.206239922@linuxfoundation.org> References: <20190904175314.206239922@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit e1b4ce25dbc93ab0cb8ed0f236a3b9ff7b03802c ] The spsc_queue_peek function is accessing queue->head which belongs to the consumer thread and shouldn't be accessed by the producer This is fixing a rare race condition when destroying entities. Signed-off-by: Christian König Acked-by: Andrey Grodzovsky Reviewed-by: Monk.liu@amd.com Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- drivers/gpu/drm/scheduler/sched_entity.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c index 35ddbec1375ae..671c90f34ede6 100644 --- a/drivers/gpu/drm/scheduler/sched_entity.c +++ b/drivers/gpu/drm/scheduler/sched_entity.c @@ -95,7 +95,7 @@ static bool drm_sched_entity_is_idle(struct drm_sched_entity *entity) rmb(); /* for list_empty to work without lock */ if (list_empty(&entity->list) || - spsc_queue_peek(&entity->job_queue) == NULL) + spsc_queue_count(&entity->job_queue) == 0) return true; return false; @@ -281,7 +281,7 @@ void drm_sched_entity_fini(struct drm_sched_entity *entity) /* Consumption of existing IBs wasn't completed. Forcefully * remove them here. */ - if (spsc_queue_peek(&entity->job_queue)) { + if (spsc_queue_count(&entity->job_queue)) { if (sched) { /* Park the kernel for a moment to make sure it isn't processing * our enity. -- 2.20.1