linux-kernel - Re: iommu/vt-d: Cure VF irqdomain hickup

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 16 Nov 2020 13:50:32 +0100
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Geert Uytterhoeven <geert@...ux-m68k.org>
Cc:     Jason Gunthorpe <jgg@...dia.com>,
        Ziyad Atiyyeh <ziyadat@...dia.com>,
        Itay Aveksis <itayav@...dia.com>,
        Moshe Shemesh <moshe@...dia.com>,
        LKML <linux-kernel@...r.kernel.org>,
        the arch/x86 maintainers <x86@...nel.org>,
        Joerg Roedel <joro@...tes.org>,
        Linux IOMMU <iommu@...ts.linux-foundation.org>,
        linux-pci <linux-pci@...r.kernel.org>,
        Bjorn Helgaas <bhelgaas@...gle.com>,
        Marc Zyngier <maz@...nel.org>,
        David Woodhouse <dwmw2@...radead.org>
Subject: Re: iommu/vt-d: Cure VF irqdomain hickup

Geert,

On Mon, Nov 16 2020 at 10:47, Geert Uytterhoeven wrote:
> On Thu, Nov 12, 2020 at 8:16 PM Thomas Gleixner <tglx@...utronix.de> wrote:
>> The recent changes to store the MSI irqdomain pointer in struct device
>> missed that Intel DMAR does not register virtual function devices.  Due to
>> that a VF device gets the plain PCI-MSI domain assigned and then issues
>> compat MSI messages which get caught by the interrupt remapping unit.
>>
>> Cure that by inheriting the irq domain from the physical function
>> device.
>>
>> That's a temporary workaround. The correct fix is to inherit the irq domain
>> from the bus, but that's a larger effort which needs quite some other
>> changes to the way how x86 manages PCI and MSI domains.
>>
>> Fixes: 85a8dfc57a0b ("iommm/vt-d: Store irq domain in struct device")
>> Reported-by: Jason Gunthorpe <jgg@...dia.com>
>> Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
>> ---
>>  drivers/iommu/intel/dmar.c |   19 ++++++++++++++++++-
>>  1 file changed, 18 insertions(+), 1 deletion(-)
>>
>> --- a/drivers/iommu/intel/dmar.c
>> +++ b/drivers/iommu/intel/dmar.c
>> @@ -333,6 +333,11 @@ static void  dmar_pci_bus_del_dev(struct
>>         dmar_iommu_notify_scope_dev(info);
>>  }
>>
>> +static inline void vf_inherit_msi_domain(struct pci_dev *pdev)
>> +{
>> +       dev_set_msi_domain(&pdev->dev, dev_get_msi_domain(&pdev->physfn->dev));
>
> If CONFIG_PCI_ATS is not set:
>
>     error: 'struct pci_dev' has no member named 'physfn'
>

thanks for pointing that out. Yet moar ifdeffery, oh well...

Thanks,

        tglx