netdev - Re: [PATCH net-next 2/2] net: stmmac: Support enhanced addressing mode for DWMAC 4.10

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] [day] [month] [year] [list]

Date:   Mon, 9 Sep 2019 17:08:46 +0200
From:   Thierry Reding <thierry.reding@...il.com>
To:     "David S . Miller" <davem@...emloft.net>
Cc:     Giuseppe Cavallaro <peppe.cavallaro@...com>,
        Alexandre Torgue <alexandre.torgue@...com>,
        Jose Abreu <joabreu@...opsys.com>,
        Jon Hunter <jonathanh@...dia.com>,
        Bitan Biswas <bbiswas@...dia.com>, netdev@...r.kernel.org,
        linux-tegra@...r.kernel.org
Subject: Re: [PATCH net-next 2/2] net: stmmac: Support enhanced addressing
 mode for DWMAC 4.10

On Mon, Sep 09, 2019 at 02:36:27PM +0200, Thierry Reding wrote:
> From: Thierry Reding <treding@...dia.com>
> 
> The address width of the controller can be read from hardware feature
> registers much like on XGMAC. Add support for parsing the ADDR64 field
> so that the DMA mask can be set accordingly.
> 
> This avoids getting swiotlb involved for DMA on Tegra186 and later.
> 
> Also make sure that the upper 32 bits of the DMA address are written to
> the DMA descriptors when enhanced addressing mode is used.
> 
> Signed-off-by: Thierry Reding <treding@...dia.com>
> ---
>  drivers/net/ethernet/stmicro/stmmac/dwmac4.h  |  1 +
>  .../ethernet/stmicro/stmmac/dwmac4_descs.c    |  4 ++--
>  .../net/ethernet/stmicro/stmmac/dwmac4_dma.c  | 20 +++++++++++++++++++
>  .../net/ethernet/stmicro/stmmac/dwmac4_dma.h  |  1 +
>  4 files changed, 24 insertions(+), 2 deletions(-)

I just ran into a case where this is not enough. The problem is that the
driver not only doesn't fill in the upper 32 bits of the DMA address in
the descriptors, it also doesn't program the upper 32 bits of the DMA
address of the descriptors when initializing the channels. I'll update
the patch for that case as well.

Thierry

Download attachment "signature.asc" of type "application/pgp-signature" (834 bytes)