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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 98E0EC04ABB for ; Thu, 13 Sep 2018 13:02:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 26EB620881 for ; Thu, 13 Sep 2018 13:02:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 26EB620881 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727734AbeIMSLU (ORCPT ); Thu, 13 Sep 2018 14:11:20 -0400 Received: from foss.arm.com ([217.140.101.70]:47368 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727006AbeIMSLU (ORCPT ); Thu, 13 Sep 2018 14:11:20 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7947E7A9; Thu, 13 Sep 2018 06:01:57 -0700 (PDT) Received: from edgewater-inn.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 4A8763F575; Thu, 13 Sep 2018 06:01:57 -0700 (PDT) Received: by edgewater-inn.cambridge.arm.com (Postfix, from userid 1000) id 7F7C21AE3411; Thu, 13 Sep 2018 14:02:14 +0100 (BST) Date: Thu, 13 Sep 2018 14:02:14 +0100 From: Will Deacon To: Andrew Murray Cc: Arnd Bergmann , yuanzhichang@hisilicon.com, dann.frazier@canonical.com, gabriele.paoloni@huawei.com, bhelgaas@google.com, andy.shevchenko@gmail.com, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, suzuki.poulose@arm.com, jean-philippe.brucker@arm.com Subject: Re: [PATCH] asm-generic: io: Fix ioport_map() for !CONFIG_GENERIC_IOMAP && CONFIG_INDIRECT_PIO Message-ID: <20180913130214.GA13242@arm.com> References: <1536842907-51732-1-git-send-email-andrew.murray@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1536842907-51732-1-git-send-email-andrew.murray@arm.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 13, 2018 at 01:48:27PM +0100, Andrew Murray wrote: > The !CONFIG_GENERIC_IOMAP version of ioport_map uses MMIO_UPPER_LIMIT to > prevent users from making I/O accesses outside the expected I/O range - > however it erroneously treats MMIO_UPPER_LIMIT as a mask which is > contradictory to its other users. > > The introduction of CONFIG_INDIRECT_PIO, which subtracts an arbitrary > amount from IO_SPACE_LIMIT to form MMIO_UPPER_LIMIT, results in ioport_map > mangling the given port rather than capping it. > > We address this by aligning more closely with the CONFIG_GENERIC_IOMAP > implementation of ioport_map by using the comparison operator and > returning NULL where the port exceeds MMIO_UPPER_LIMIT. Though note that > we preserve the existing behavior of masking with IO_SPACE_LIMIT such that > we don't break existing buggy drivers that somehow rely on this masking. > > Fixes: 5745392e0c2b ("PCI: Apply the new generic I/O management on PCI IO hosts") > Reported-by: Will Deacon > Signed-off-by: Andrew Murray > --- > include/asm-generic/io.h | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h > index 66d1d45..d356f80 100644 > --- a/include/asm-generic/io.h > +++ b/include/asm-generic/io.h > @@ -1026,7 +1026,8 @@ static inline void __iomem *ioremap_wt(phys_addr_t offset, size_t size) > #define ioport_map ioport_map > static inline void __iomem *ioport_map(unsigned long port, unsigned int nr) > { > - return PCI_IOBASE + (port & MMIO_UPPER_LIMIT); > + port &= IO_SPACE_LIMIT; > + return (port > MMIO_UPPER_LIMIT) ? NULL : PCI_IOBASE + port; > } > #endif Thanks, that fixes legacy virtio PCI devices under kvmtool, so: Tested-by: Will Deacon Will