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=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 C6036C2D0DB for ; Tue, 28 Jan 2020 14:35:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9D7AA207FD for ; Tue, 28 Jan 2020 14:35:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580222104; bh=CBaszSDNlm5NoSx/zARR8prZi4DXJ4Y5llwvvqesr1I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=i8jIwyJwzMq/yRlQ+HLwfi4obatP5Fa62z17ZK17jDert73/iRLczOWZotQtPs2/c vChGe/wU3W2YzkgGP4UVdGjAm85tOl85VJ3QSCGHWe02HgV6coKd/EvnE3EFtPvzkE Ren0+oZxQCrquZhmralTkx038rw7WT3q1JZxj2UU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731078AbgA1OXZ (ORCPT ); Tue, 28 Jan 2020 09:23:25 -0500 Received: from mail.kernel.org ([198.145.29.99]:49374 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731005AbgA1OXS (ORCPT ); Tue, 28 Jan 2020 09:23:18 -0500 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 D690521739; Tue, 28 Jan 2020 14:23:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580221398; bh=CBaszSDNlm5NoSx/zARR8prZi4DXJ4Y5llwvvqesr1I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Cp8JPPY/oQGF4HleYDubjK5g8RTJSxDg6NLrCiEF4LS12vDZ8r0i8gQVik74Ix2/k /++iN5wrLYZMheD9cmCaniE/RD85K+cMeApGf9f0IPwTDQW7U1WJ1qvzAz8R60XmOq uPyZ8ZRwOcd+GQPu6OVuj04tvJqxcVWKiul5VkFc= 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 4.9 208/271] nvme: retain split access workaround for capability reads Date: Tue, 28 Jan 2020 15:05:57 +0100 Message-Id: <20200128135908.029090090@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200128135852.449088278@linuxfoundation.org> References: <20200128135852.449088278@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 1ac4cec5f4f7c..e2bce9385eda6 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1863,7 +1863,7 @@ 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