netdev - Re: [RFC PATCH] usb: hcd: warn about URB buffers that are not DMA aligned and are about to be DMA mapped

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: <51BD94F5.2060803@iki.fi>
Date:	Sun, 16 Jun 2013 13:35:33 +0300
From:	Jussi Kivilinna <jussi.kivilinna@....fi>
To:	Oliver Neukum <oliver@...kum.org>
CC:	Ming Lei <tom.leiming@...il.com>, linux-usb@...r.kernel.org,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Network Development <netdev@...r.kernel.org>
Subject: Re: [RFC PATCH] usb: hcd: warn about URB buffers that are not DMA
 aligned and are about to be DMA mapped

On 16.06.2013 11:21, Oliver Neukum wrote:
> On Saturday 15 June 2013 16:22:30 Jussi Kivilinna wrote:
> 
>> Hm.. rethink this a bit.
>>
>> Transfer buffer might be dma aligned but shorter than cacheline and end of cacheline
>> used as something else. Manual alignment by host driver does not catch that
>> or fix that.
>> So, yes.. dma mapping should work with unaligned buffers, but maybe the actual
>> problem is multiple buffers from same cacheline.
> 
> The buffers kmalloc() returns are OK in that regard. A driver that uses
> a buffer for anything but buffering is buggy.

Ok, I'll look at that direction. Thanks.

-Jussi

> 
> 	Regards
> 		Oliver
> 
> 

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html