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=-20.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 54ABFC4332F for ; Fri, 24 Sep 2021 13:00:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 37E0F6124C for ; Fri, 24 Sep 2021 13:00:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344472AbhIXNB4 (ORCPT ); Fri, 24 Sep 2021 09:01:56 -0400 Received: from mail.kernel.org ([198.145.29.99]:56170 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344515AbhIXM7v (ORCPT ); Fri, 24 Sep 2021 08:59:51 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 44B6A6136A; Fri, 24 Sep 2021 12:53:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1632488015; bh=Y0ifqwM0ik/0txa17mlwIy+/Fc1YXrdfnwMXOUfSEUc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IrRSOT5xZLgRkMvxLMWErqyjDG3kXT3LzmoVxxIkhHvzj5GPgL34Mi9fnXQMR0bSw 0vZnvnBY1mJc+yoNqWFzAO/8y8wgcRwFu4EJsSu2YMOBupEnavlJqUQ2b5Av9eOFNE ccgt0PvQFVre2jS+kluukK0t/rECSrSs/YQFBMds= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, xinhui pan , =?UTF-8?q?Christian=20K=C3=B6nig?= , Dave Airlie , Sasha Levin Subject: [PATCH 5.14 051/100] drm/ttm: Fix a deadlock if the target BO is not idle during swap Date: Fri, 24 Sep 2021 14:44:00 +0200 Message-Id: <20210924124343.150751601@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210924124341.214446495@linuxfoundation.org> References: <20210924124341.214446495@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: xinhui pan [ Upstream commit 70982eef4d7eebb47a3b1ef25ec1bc742f3a21cf ] The ret value might be -EBUSY, caller will think lru lock is still locked but actually NOT. So return -ENOSPC instead. Otherwise we hit list corruption. ttm_bo_cleanup_refs might fail too if BO is not idle. If we return 0, caller(ttm_tt_populate -> ttm_global_swapout ->ttm_device_swapout) will be stuck as we actually did not free any BO memory. This usually happens when the fence is not signaled for a long time. Signed-off-by: xinhui pan Reviewed-by: Christian König Fixes: ebd59851c796 ("drm/ttm: move swapout logic around v3") Link: https://patchwork.freedesktop.org/patch/msgid/20210907040832.1107747-1-xinhui.pan@amd.com Signed-off-by: Christian König Signed-off-by: Dave Airlie Signed-off-by: Sasha Levin --- drivers/gpu/drm/ttm/ttm_bo.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index 32202385073a..b47a5053eb85 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -1157,9 +1157,9 @@ int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx, } if (bo->deleted) { - ttm_bo_cleanup_refs(bo, false, false, locked); + ret = ttm_bo_cleanup_refs(bo, false, false, locked); ttm_bo_put(bo); - return 0; + return ret == -EBUSY ? -ENOSPC : ret; } ttm_bo_del_from_lru(bo); @@ -1213,7 +1213,7 @@ out: if (locked) dma_resv_unlock(bo->base.resv); ttm_bo_put(bo); - return ret; + return ret == -EBUSY ? -ENOSPC : ret; } void ttm_bo_tt_destroy(struct ttm_buffer_object *bo) -- 2.33.0