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,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 11118C2D0DB for ; Fri, 24 Jan 2020 11:33:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D7D5720704 for ; Fri, 24 Jan 2020 11:33:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579865590; bh=QxKbSpHZntZauEiARxlmuXAbUDqksp+NtwrnoUJp3qQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=JwIXFNORN6JSwUyDci4TeFxysb5h5TSDa2pslQqM1FB/IoSFsi7ysrLKgj6bf7iJS gfE1PJxcv76T4gYRhuUJsw2YxCmut9GIGQe/7Ak9CFnVruwSFG/wlaQjo9b+VsviYe BW3witGzx9cSQfgPqlXNTYZ52n9OeRzGy1SSp3+M= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404549AbgAXLdK (ORCPT ); Fri, 24 Jan 2020 06:33:10 -0500 Received: from mail.kernel.org ([198.145.29.99]:52416 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391908AbgAXLdF (ORCPT ); Fri, 24 Jan 2020 06:33:05 -0500 Received: from localhost (ip-213-127-102-57.ip.prioritytelecom.net [213.127.102.57]) (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 6EDEE20704; Fri, 24 Jan 2020 11:33:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579865585; bh=QxKbSpHZntZauEiARxlmuXAbUDqksp+NtwrnoUJp3qQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ilZWFYbNQdw7cfcpAbFStHlWFvqFuF2hn7eJEIzfy/3D2g6PPidKpGCxD7wQz6l4G vS3A/e8pgc8Rrf5qfGZZdwwOGX4bpLEdwieWgFBhPZTmycxYFkWHaottKVpySc/4Kw fhFJVPZOBHign6Ib3tjiMpvBCohxV1rb6Sp6eemA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ard Biesheuvel , Sagi Grimberg , Sasha Levin Subject: [PATCH 4.19 586/639] nvme: retain split access workaround for capability reads Date: Fri, 24 Jan 2020 10:32:36 +0100 Message-Id: <20200124093202.878097814@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200124093047.008739095@linuxfoundation.org> References: <20200124093047.008739095@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 From: Ard Biesheuvel [ Upstream commit 3a8ecc935efabdad106b5e06d07b150c394b4465 ] Commit 7fd8930f26be4 "nvme: add a common helper to read Identify Controller data" has re-introduced an issue that we have attempted to work around in the past, in commit a310acd7a7ea ("NVMe: use split lo_hi_{read,write}q"). The problem is that some PCIe NVMe controllers do not implement 64-bit outbound accesses correctly, which is why the commit above switched to using lo_hi_[read|write]q for all 64-bit BAR accesses occuring in the code. In the mean time, the NVMe subsystem has been refactored, and now calls into the PCIe support layer for NVMe via a .reg_read64() method, which fails to use lo_hi_readq(), and thus reintroduces the problem that the workaround above aimed to address. Given that, at the moment, .reg_read64() is only used to read the capability register [which is known to tolerate split reads], let's switch .reg_read64() to lo_hi_readq() as well. This fixes a boot issue on some ARM boxes with NVMe behind a Synopsys DesignWare PCIe host controller. Fixes: 7fd8930f26be4 ("nvme: add a common helper to read Identify Controller data") Signed-off-by: Ard Biesheuvel Signed-off-by: Sagi Grimberg Signed-off-by: Sasha Levin --- drivers/nvme/host/pci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 124f41157173e..3c68a5b35ec1b 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -2396,7 +2396,7 @@ static int nvme_pci_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val) static int nvme_pci_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val) { - *val = readq(to_nvme_dev(ctrl)->bar + off); + *val = lo_hi_readq(to_nvme_dev(ctrl)->bar + off); return 0; } -- 2.20.1