netdev - Re: [PATCH 3/4] net: qcom/emac: enforce DMA address restrictions

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 for Android: free password hash cracker in your pocket

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

Date:   Thu, 12 Oct 2017 11:52:58 -0500
From:   Timur Tabi <timur@...eaurora.org>
To:     David Laight <David.Laight@...LAB.COM>,
        "David S. Miller" <davem@...emloft.net>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: Re: [PATCH 3/4] net: qcom/emac: enforce DMA address restrictions

On 10/12/2017 11:20 AM, David Laight wrote:
>> I'm pretty sure that kzalloc does not make that guarantee, and I don't
>> think dma_alloc_coherent does either.

> dma_alloc_coherent() definitely does.
> And I've a driver that relies on it (for 16k blocks).

What about when an IOMMU is used?  The DMA address that gets returned is 
not necessarily the physical address of the memory buffer.

-- 
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
Technologies, Inc.  Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.