linux-kernel - Re: [PATCH][RFC] PCI: rcar: Add bus notifier so we can limit the DMA range

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-next>] [day] [month] [year] [list]

Message-ID: <20180604223048.GC30381@bhelgaas-glaptop.roam.corp.google.com>
Date:   Mon, 4 Jun 2018 17:30:48 -0500
From:   Bjorn Helgaas <helgaas@...nel.org>
To:     Marek Vasut <marek.vasut@...il.com>
Cc:     Arnd Bergmann <arnd@...db.de>,
        linux-pci <linux-pci@...r.kernel.org>,
        Phil Edworthy <phil.edworthy@...esas.com>,
        Marek Vasut <marek.vasut+renesas@...il.com>,
        Geert Uytterhoeven <geert+renesas@...der.be>,
        Simon Horman <horms+renesas@...ge.net.au>,
        Wolfram Sang <wsa@...-dreams.de>,
        Linux-Renesas <linux-renesas-soc@...r.kernel.org>,
        Nikita Yushchenko <nikita.yoush@...entembedded.com>,
        Catalin Marinas <catalin.marinas@....com>,
        Will Deacon <will.deacon@....com>,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH][RFC] PCI: rcar: Add bus notifier so we can limit the DMA
 range

[+cc ARM64 folks, linux-kernel]

The original patch under discussion is:
https://lkml.kernel.org/r/20180521220514.30256-1-marek.vasut+renesas@gmail.com

On Tue, May 22, 2018 at 11:52:21AM +0200, Marek Vasut wrote:
> On 05/22/2018 10:10 AM, Arnd Bergmann wrote:
> > On Tue, May 22, 2018 at 12:05 AM, Marek Vasut <marek.vasut@...il.com> wrote:
> >> From: Phil Edworthy <phil.edworthy@...esas.com>
> >>
> >> The PCIe DMA controller on RCar Gen2 and earlier is on 32bit bus,
> >> so limit the DMA range to 32bit.
> >>
> >> Signed-off-by: Phil Edworthy <phil.edworthy@...esas.com>
> >> Signed-off-by: Marek Vasut <marek.vasut+renesas@...il.com>
> >> Cc: Arnd Bergmann <arnd@...db.de>
> >> Cc: Geert Uytterhoeven <geert+renesas@...der.be>
> >> Cc: Phil Edworthy <phil.edworthy@...esas.com>
> >> Cc: Simon Horman <horms+renesas@...ge.net.au>
> >> Cc: Wolfram Sang <wsa@...-dreams.de>
> >> Cc: linux-renesas-soc@...r.kernel.org
> >> To: linux-pci@...r.kernel.org
> >> ---
> >> NOTE: I'm aware of https://patchwork.kernel.org/patch/9495895/ , but the
> >>       discussion seems to have gone way off, so I'm sending this as a
> >>       RFC. Any feedback on how to do this limiting properly would be nice.
> > 
> > Doing it in the driver is clearly not appropriate, we must do this in
> > common code. If I remember correctly, it's specifically ARM64 that is
> > broken here, it incorrectly allows setting a DMA mask to 64 bit
> > when that is not available.
> 
> Yep, that's correct. ARM64 with devices mapping tremendous amounts of
> memory. So did anything change since that discussion references in the NOTE?
> 
> -- 
> Best regards,
> Marek Vasut