From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:40404 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753042AbcBNW2i (ORCPT ); Sun, 14 Feb 2016 17:28:38 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tejun Heo , Andy Lutomirski , Sergei Shtylyov Subject: [PATCH 4.4 089/117] libata: disable forced PORTS_IMPL for >= AHCI 1.3 Date: Sun, 14 Feb 2016 14:22:06 -0800 Message-Id: <20160214222144.099422386@linuxfoundation.org> In-Reply-To: <20160214222141.393531627@linuxfoundation.org> References: <20160214222141.393531627@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tejun Heo commit 566d1827df2ef0cbe921d3d6946ac3007b1a6938 upstream. Some early controllers incorrectly reported zero ports in PORTS_IMPL register and the ahci driver fabricates PORTS_IMPL from the number of ports in those cases. This hasn't mattered but with the new nvme controllers there are cases where zero PORTS_IMPL is valid and should be honored. Disable the workaround for >= AHCI 1.3. Signed-off-by: Tejun Heo Reported-by: Andy Lutomirski Link: http://lkml.kernel.org/g/CALCETrU7yMvXEDhjAUShoHEhDwifJGapdw--BKxsP0jmjKGmRw@mail.gmail.com Cc: Sergei Shtylyov Signed-off-by: Greg Kroah-Hartman --- drivers/ata/libahci.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/ata/libahci.c +++ b/drivers/ata/libahci.c @@ -495,8 +495,8 @@ void ahci_save_initial_config(struct dev } } - /* fabricate port_map from cap.nr_ports */ - if (!port_map) { + /* fabricate port_map from cap.nr_ports for < AHCI 1.3 */ + if (!port_map && vers < 0x10300) { port_map = (1 << ahci_nr_ports(cap)) - 1; dev_warn(dev, "forcing PORTS_IMPL to 0x%x\n", port_map);