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=-0.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 6142DC04AB3 for ; Mon, 27 May 2019 22:55:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1BAB62075C for ; Mon, 27 May 2019 22:55:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=anastas.io header.i=@anastas.io header.b="KYnxCoTK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726979AbfE0Wz3 (ORCPT ); Mon, 27 May 2019 18:55:29 -0400 Received: from alpha.anastas.io ([104.248.188.109]:50915 "EHLO alpha.anastas.io" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726931AbfE0Wz3 (ORCPT ); Mon, 27 May 2019 18:55:29 -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 A62387F8EF; Mon, 27 May 2019 17:55:27 -0500 (CDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=anastas.io; s=mail; t=1558997728; bh=Fkmg//rw0SZv0cbWNfledPODm9FWrb76L5Rv9PgTLBY=; h=From:To:Cc:Subject:Date:From; b=KYnxCoTKhTuTLyhPQ9l7D0X2LQ1u9/v9EF6WIjyAIkGsxZapfKdJfCpKuzldE9/tV 4R3gruWPlNmAWyW2HDhIwadCiXQ8ZuZWcEHfZ2O0Eu0FC5/1CMb72muXchdDkApBTn +dSD3EsJxF/uk8LU8FNzBOKp03olHpsMHRbNEBbRjWuhXAnxKa/XH1g88+woGtTm2K i2BEWoeceJ/18T8pi9UBuSzYOP52bNSlukwMM6N35d5PV5+5Xw4hnPAnfYT1t3TfSv BdPyDgZ3Qe/Wf3VRiIuZc8RHmxNUN78giREcHNxNCyogASoHwzMugE37WnzBnq7c+X mcEW2jKASskmA== 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: [RESEND PATCH 0/3] Allow custom PCI resource alignment on pseries Date: Mon, 27 May 2019 17:55:18 -0500 Message-Id: <20190527225521.5884-1-shawn@anastas.io> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org 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 +++++++-- 5 files changed, 46 insertions(+), 4 deletions(-) -- 2.20.1