linux-kernel - Re: [PATCH v2 2/2] PCI: dwc: add support for 64-bit MSI target address

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]

Message-ID: <20220810213023.GB557589-robh@kernel.org>
Date:   Wed, 10 Aug 2022 15:30:23 -0600
From:   Rob Herring <robh@...nel.org>
To:     Will McVicker <willmcvicker@...gle.com>
Cc:     Jingoo Han <jingoohan1@...il.com>,
        Gustavo Pimentel <gustavo.pimentel@...opsys.com>,
        Lorenzo Pieralisi <lpieralisi@...nel.org>,
        Krzysztof Wilczyński <kw@...ux.com>,
        Bjorn Helgaas <bhelgaas@...gle.com>, kernel-team@...roid.com,
        Vidya Sagar <vidyas@...dia.com>,
        kernel test robot <lkp@...el.com>,
        "Isaac J . Manjarres" <isaacmanjarres@...gle.com>,
        linux-pci@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 2/2] PCI: dwc: add support for 64-bit MSI target
 address

On Wed, Aug 10, 2022 at 06:35:35PM +0000, Will McVicker wrote:
> Since not all devices require a 32-bit MSI address, add support to the
> PCIe host driver to allow setting the DMA mask to 64-bits. This allows
> kernels to disable ZONE_DMA32 and bounce buffering (swiotlb) without
> risking not being able to get a 32-bit address during DMA allocation.
> Basically, in the slim chance that there are no 32-bit allocations
> available, the current PCIe host driver will fail to allocate the
> msi_msg page due to a DMA address overflow (seen in [1]). With this
> patch, the PCIe driver can advertise 64-bit support via it's MSI
> capabilities to hint to the PCIe host driver to set the DMA mask to
> 64-bits.
> 
> [1] https://lore.kernel.org/all/Yo0soniFborDl7+C@google.com/
> 
> Reported-by: kernel test robot <lkp@...el.com>
> Signed-off-by: Will McVicker <willmcvicker@...gle.com>
> ---
>  drivers/pci/controller/dwc/pcie-designware-host.c | 14 ++++++++++++--
>  drivers/pci/controller/dwc/pcie-designware.c      |  9 +++++++++
>  drivers/pci/controller/dwc/pcie-designware.h      |  1 +
>  3 files changed, 22 insertions(+), 2 deletions(-)

Reviewed-by: Rob Herring <robh@...nel.org>