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=-20.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 46A0CC433ED for ; Sat, 17 Apr 2021 12:06:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 164AC610CD for ; Sat, 17 Apr 2021 12:06:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236219AbhDQMHR (ORCPT ); Sat, 17 Apr 2021 08:07:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235901AbhDQMHQ (ORCPT ); Sat, 17 Apr 2021 08:07:16 -0400 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BEFFDC061574; Sat, 17 Apr 2021 05:06:49 -0700 (PDT) Received: from zn.tnic (p200300ec2f1c4200f944f17f6d67a0aa.dip0.t-ipconnect.de [IPv6:2003:ec:2f1c:4200:f944:f17f:6d67:a0aa]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 933AA1EC0350; Sat, 17 Apr 2021 14:06:47 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1618661207; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=nE6tv9CArLBjdf6W3ZCG71idf2Qt9t0kDlmZ+4D8pSc=; b=H4/8MQ5yqeigh9WNAzQEC0yDybE2CkoSe1v4H8L9Q+J1bwWN98kcVZYQxpm5OtKomBAjdO XzZpA8q1ytefHhfDutAA+BDAS1W0FHfhOZE8hgFk9b25InZrDkVKWC3JXVcNk9E08yHEyO QFXvIZBlIRrel5LFFQbn57A7rc5suMo= Date: Sat, 17 Apr 2021 14:06:44 +0200 From: Borislav Petkov To: Jean-Philippe Brucker Cc: linux-tip-commits@vger.kernel.org, Jean-Philippe Brucker , x86@kernel.org, linux-kernel@vger.kernel.org, =?utf-8?B?SsO2cmcgUsO2ZGVs?= Subject: Re: [tip: x86/urgent] x86/dma: Tear down DMA ops on driver unbind Message-ID: <20210417120644.GA5235@zn.tnic> References: <20210414082633.877461-1-jean-philippe@linaro.org> <161847725788.29796.15623166781765421094.tip-bot2@tip-bot2> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <161847725788.29796.15623166781765421094.tip-bot2@tip-bot2> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 15, 2021 at 09:00:57AM -0000, tip-bot2 for Jean-Philippe Brucker wrote: > The following commit has been merged into the x86/urgent branch of tip: > > Commit-ID: 9f8614f5567eb4e38579422d38a1bdfeeb648ffc > Gitweb: https://git.kernel.org/tip/9f8614f5567eb4e38579422d38a1bdfeeb648ffc > Author: Jean-Philippe Brucker > AuthorDate: Wed, 14 Apr 2021 10:26:34 +02:00 > Committer: Borislav Petkov > CommitterDate: Thu, 15 Apr 2021 10:27:29 +02:00 > > x86/dma: Tear down DMA ops on driver unbind > > Since > > 08a27c1c3ecf ("iommu: Add support to change default domain of an iommu group") > > a user can switch a device between IOMMU and direct DMA through sysfs. > This doesn't work for AMD IOMMU at the moment because dev->dma_ops is > not cleared when switching from a DMA to an identity IOMMU domain. The > DMA layer thus attempts to use the dma-iommu ops on an identity domain, > causing an oops: > > # echo 0000:00:05.0 > /sys/sys/bus/pci/drivers/e1000e/unbind > # echo identity > /sys/bus/pci/devices/0000:00:05.0/iommu_group/type > # echo 0000:00:05.0 > /sys/sys/bus/pci/drivers/e1000e/bind > ... > BUG: kernel NULL pointer dereference, address: 0000000000000028 > ... > Call Trace: > iommu_dma_alloc > e1000e_setup_tx_resources > e1000e_open > > Implement arch_teardown_dma_ops() on x86 to clear the device's dma_ops > pointer during driver unbind. > > [ bp: Massage commit message. ] > > Fixes: 08a27c1c3ecf ("iommu: Add support to change default domain of an iommu group") > Signed-off-by: Jean-Philippe Brucker > Signed-off-by: Borislav Petkov > Link: https://lkml.kernel.org/r/20210414082633.877461-1-jean-philippe@linaro.org > --- > arch/x86/Kconfig | 1 + > arch/x86/kernel/pci-dma.c | 7 +++++++ > 2 files changed, 8 insertions(+) > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index 2792879..2c90f8d 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -85,6 +85,7 @@ config X86 > select ARCH_HAS_STRICT_MODULE_RWX > select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE > select ARCH_HAS_SYSCALL_WRAPPER > + select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_DMA > select ARCH_HAS_UBSAN_SANITIZE_ALL > select ARCH_HAS_DEBUG_WX > select ARCH_HAVE_NMI_SAFE_CMPXCHG > diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c > index de234e7..60a4ec2 100644 > --- a/arch/x86/kernel/pci-dma.c > +++ b/arch/x86/kernel/pci-dma.c > @@ -154,3 +154,10 @@ static void via_no_dac(struct pci_dev *dev) > DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_VENDOR_ID_VIA, PCI_ANY_ID, > PCI_CLASS_BRIDGE_PCI, 8, via_no_dac); > #endif > + > +#ifdef CONFIG_ARCH_HAS_TEARDOWN_DMA_OPS > +void arch_teardown_dma_ops(struct device *dev) > +{ > + set_dma_ops(dev, NULL); > +} > +#endif Nope, sorry, no joy. Zapping it from tip. With that patch, it fails booting on my test box with messages like (typing up from video I took): ... ata: softreset failed (1st FIS failed) ahci 0000:03:00:1: AMD-Vi: Event logged [IO_PAGE_FAULT domain=...] ahci 0000:03:00:1: AMD-Vi: Event logged [IO_PAGE_FAULT domain=...] <--- EOF -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette