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,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 0CE25C33CAF for ; Thu, 16 Jan 2020 18:38:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CC43B2073A for ; Thu, 16 Jan 2020 18:38:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579199910; bh=6z52yvYtN4PgC4snKq0U9AwSafv+Pt5ZFMUFZUObv7s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=z6feClX2JoYSLaYmTqGxtphPF9ZzGzQNLovp3+sV1kBmBY32dE7mI1JRfnrDq3xA6 PjefGs3ZeLyWHe9h3jcdepo152QyKp4n9grKfgrokURi0CcE467s1Tz17SHM4OY/VX +l9PqNRceh68msUCq4+U7Ku/cW6Mod1lVrFWjs94= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390133AbgAPRM2 (ORCPT ); Thu, 16 Jan 2020 12:12:28 -0500 Received: from mail.kernel.org ([198.145.29.99]:55058 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389851AbgAPRMZ (ORCPT ); Thu, 16 Jan 2020 12:12:25 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (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 409CD24692; Thu, 16 Jan 2020 17:12:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579194744; bh=6z52yvYtN4PgC4snKq0U9AwSafv+Pt5ZFMUFZUObv7s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Cem/SlXrpFpYJFF73kgZVTOrYKJJK5X3I7ld2AO5EjkoEttP6IKR/wzgiLQe/dKTu /DnR3AhOIYHm+3eTjH/jr6B+trnnPxQhxquNkVgaNwJ455IUtZPsz5Ib1tww1T3Pxw PJe8XEauT1hdDslurrbXFqNDQF0VtE0yaDpKjvCc= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ard Biesheuvel , Sagi Grimberg , Sasha Levin , linux-nvme@lists.infradead.org Subject: [PATCH AUTOSEL 4.19 574/671] nvme: retain split access workaround for capability reads Date: Thu, 16 Jan 2020 12:03:32 -0500 Message-Id: <20200116170509.12787-311-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116170509.12787-1-sashal@kernel.org> References: <20200116170509.12787-1-sashal@kernel.org> MIME-Version: 1.0 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: 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 124f41157173..3c68a5b35ec1 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