From patchwork Tue May 28 01:54:09 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shawn Anastasio X-Patchwork-Id: 10963629 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A81CD14C0 for ; Tue, 28 May 2019 01:54:19 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 968AC285E0 for ; Tue, 28 May 2019 01:54:19 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 87C2A285F7; Tue, 28 May 2019 01:54:19 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 77C86285E0 for ; Tue, 28 May 2019 01:54:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727566AbfE1ByR (ORCPT ); Mon, 27 May 2019 21:54:17 -0400 Received: from alpha.anastas.io ([104.248.188.109]:59707 "EHLO alpha.anastas.io" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727589AbfE1ByR (ORCPT ); Mon, 27 May 2019 21:54:17 -0400 Received: from authenticated-user (alpha.anastas.io [104.248.188.109]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alpha.anastas.io (Postfix) with ESMTPSA id 3463D7F8BF; Mon, 27 May 2019 20:54:16 -0500 (CDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=anastas.io; s=mail; t=1559008457; bh=tpEsBHAskNTnW0j20OuJzsmsrKEuGoeRDaQ9ZdKXp/w=; h=From:To:Cc:Subject:Date:From; b=fq9dYa7k3w1qHhjjNrXEPO8ZdlXOywirbS07vJHK1h62LmGCzS6ixZdpGfH3eNp1E ggYjWoJKhajFsLBGLNc35lFBGVyulfwQEXNmNddElEY+ZBzae+eAlJZ4atku5H2smB QvhZ5EGwQ21IyGssQGMcviHcJ/SGc0vl4Z7ynhEhAhB1pyH0vSC9+UoJF3Z4X/kwOu hIjKwZFDPUj++VAgfpjhXvRqknfAfuefv5eV1bD74WaeqGRgikxvyWkR+nMCRJeY6c jMP8KSFpYNUVcTvG66I4xPgRQOuQ1sXeYjgwbt8eKBM6PAOF6ZP5P9bxHn8xsEUmMd imioSVa6mUW9g== From: Shawn Anastasio To: linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Cc: bhelgaas@google.com, benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, sbobroff@linux.ibm.com, xyjxie@linux.vnet.ibm.com, rppt@linux.ibm.com, linux-kernel@vger.kernel.org Subject: [PATCH v2 0/3] Allow custom PCI resource alignment on pseries Date: Mon, 27 May 2019 20:54:09 -0500 Message-Id: <20190528015412.30521-1-shawn@anastas.io> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Changes from v1 to v2: - Fix function declaration warnings caught by sparse Hello all, This patch set implements support for user-specified PCI resource alignment on the pseries platform for hotplugged PCI devices. Currently on pseries, PCI resource alignments specified with the pci=resource_alignment commandline argument are ignored, since the firmware is in charge of managing the PCI resources. In the case of hotplugged devices, though, the kernel is in charge of configuring the resources and should obey alignment requirements. The current behavior of ignoring the alignment for hotplugged devices results in sub-page BARs landing between page boundaries and becoming un-mappable from userspace via the VFIO framework. This issue was observed on a pseries KVM guest with hotplugged ivshmem devices. With these changes, users can specify an appropriate pci=resource_alignment argument on boot for devices they wish to use with VFIO. In the future, this could be extended to provide page-aligned resources by default for hotplugged devices, similar to what is done on powernv by commit 382746376993 ("powerpc/powernv: Override pcibios_default_alignment() to force PCI devices to be page aligned"). Feedback is appreciated. Thanks, Shawn Shawn Anastasio (3): PCI: Introduce pcibios_ignore_alignment_request powerpc/64: Enable pcibios_after_init hook on ppc64 powerpc/pseries: Allow user-specified PCI resource alignment after init arch/powerpc/include/asm/machdep.h | 6 ++++-- arch/powerpc/kernel/pci-common.c | 9 +++++++++ arch/powerpc/kernel/pci_64.c | 4 ++++ arch/powerpc/platforms/pseries/setup.c | 22 ++++++++++++++++++++++ drivers/pci/pci.c | 9 +++++++-- include/linux/pci.h | 1 + 6 files changed, 47 insertions(+), 4 deletions(-)