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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 4EF7BC3A589 for ; Tue, 20 Aug 2019 13:42:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1A82222DA7 for ; Tue, 20 Aug 2019 13:42:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566308524; bh=pULf/NAYntD2MtpyYU9EQBMbQQn9+vSDDP6Lf4XG7O4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=LJRj0osDmQNw6Uo55OiSiTpKh5+RMCVX5VbhdPknq3gv9QijomjYjlBczBypH7cCm 3V5y04Jn69hZDTeibC0RWki+MYIE4kL95JCO7eJ3WhD3mEVpnHuwLEzovg7ZzOJVYb WvOQwtCHG4a0BamkHthIYdGgqmUevawSYGfvs8OI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730522AbfHTNmC (ORCPT ); Tue, 20 Aug 2019 09:42:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:37144 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730090AbfHTNl7 (ORCPT ); Tue, 20 Aug 2019 09:41:59 -0400 Received: from sasha-vm.mshome.net (unknown [12.236.144.82]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id AA53D22DA7; Tue, 20 Aug 2019 13:41:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566308518; bh=pULf/NAYntD2MtpyYU9EQBMbQQn9+vSDDP6Lf4XG7O4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nedVEDSNL7wNplWLctnBEY2jd7JaODrWrK6TxF24zkKNJZiGR+F7y+dKCoH1lDp/a wvTh6quGYc5todUCvuLBzSHTGBRGBbGKwI9vrf3K12Xc4N6gpSoARNBLgZ4lZcv+KY EagH8F/HTeRM00oT7u/ImTOz7LwOgQhUHFhHk3cY= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: =?UTF-8?q?Christian=20K=C3=B6nig?= , Andrey Grodzovsky , Monk.liu@amd.com, Alex Deucher , Sasha Levin , dri-devel@lists.freedesktop.org Subject: [PATCH AUTOSEL 5.2 40/44] drm/scheduler: use job count instead of peek Date: Tue, 20 Aug 2019 09:40:24 -0400 Message-Id: <20190820134028.10829-40-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190820134028.10829-1-sashal@kernel.org> References: <20190820134028.10829-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Christian König [ 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