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=-9.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH,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 5D3A6C072B1 for ; Thu, 30 May 2019 04:45:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3754F25B40 for ; Thu, 30 May 2019 04:45:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559191523; bh=kSDMB93qouo8XN377zhespyfUO9e7dXJqdZ0dU7pCV4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=aE5PXEe+yTC7KM9rlOeustUOkrt1HterOH2WVXbl/NbEApiv2kbGs5OTnSjzgxiVS 3qXjE75fjyo+8ir9ecFZMZr+u7p0cckr2c5h3mJudKWPuY3ais6tGsb/Sg47vKsXVE 5EU0lP2BQwsZikut3f30cpWdqO+rr0dobRVkiHL8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728179AbfE3EpV (ORCPT ); Thu, 30 May 2019 00:45:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:52678 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728717AbfE3DLw (ORCPT ); Wed, 29 May 2019 23:11:52 -0400 Received: from localhost (ip67-88-213-2.z213-88-67.customer.algx.net [67.88.213.2]) (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 107B124503; Thu, 30 May 2019 03:11:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559185912; bh=kSDMB93qouo8XN377zhespyfUO9e7dXJqdZ0dU7pCV4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=B747tFAMcIwJszqD6SM7cZR/qKAIS07in9JS3YaqV6MXDxfZJMvChZuCXaUeW71ar l6j4M/jgn6PfIf97F91uQzf5OnHdnyMYcDE46lAwdew8D0Q5mFGjrNAaNXz7px1i3K qdSnF178Nq+zi+Z1eTX5WTk/T2XJ236kPspVHfV4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Oded Gabbay , Sasha Levin Subject: [PATCH 5.1 284/405] habanalabs: prevent CPU soft lockup on Palladium Date: Wed, 29 May 2019 20:04:42 -0700 Message-Id: <20190530030555.249995994@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190530030540.291644921@linuxfoundation.org> References: <20190530030540.291644921@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [ Upstream commit e850b89f50d2c1439f58d547b888ee6e43312dea ] Unmapping ptes in the device MMU on Palladium can take a long time, which can cause a kernel BUG of CPU soft lockup. This patch minimize the chances for this bug by sleeping a little between unmapping ptes. Signed-off-by: Oded Gabbay Signed-off-by: Sasha Levin --- drivers/misc/habanalabs/memory.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/misc/habanalabs/memory.c b/drivers/misc/habanalabs/memory.c index ce1fda40a8b81..fadaf557603f5 100644 --- a/drivers/misc/habanalabs/memory.c +++ b/drivers/misc/habanalabs/memory.c @@ -1046,10 +1046,17 @@ static int unmap_device_va(struct hl_ctx *ctx, u64 vaddr) mutex_lock(&ctx->mmu_lock); - for (i = 0 ; i < phys_pg_pack->npages ; i++, next_vaddr += page_size) + for (i = 0 ; i < phys_pg_pack->npages ; i++, next_vaddr += page_size) { if (hl_mmu_unmap(ctx, next_vaddr, page_size)) dev_warn_ratelimited(hdev->dev, - "unmap failed for vaddr: 0x%llx\n", next_vaddr); + "unmap failed for vaddr: 0x%llx\n", next_vaddr); + + /* unmapping on Palladium can be really long, so avoid a CPU + * soft lockup bug by sleeping a little between unmapping pages + */ + if (hdev->pldm) + usleep_range(500, 1000); + } hdev->asic_funcs->mmu_invalidate_cache(hdev, true); -- 2.20.1