linux-kernel - Re: Allocating buffers for USB transfers (again)

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]

Message-ID: <CACTFLAPztC8m4WhUdAxQyKu0F9croLK03q6c7=MbA=VqPer+6g@mail.gmail.com>
Date:	Fri, 8 Jul 2011 17:13:08 +0200
From:	Daniel Mack <zonque@...il.com>
To:	Oliver Neukum <oliver@...kum.org>
Cc:	linux-usb@...r.kernel.org, alsa-devel@...a-project.org,
	Takashi Iwai <tiwai@...e.de>,
	Clemens Ladisch <clemens@...isch.de>, florian@...kler.org,
	pedrib@...il.com, William Light <wrl@...est.net>,
	Greg KH <greg@...ah.com>, linux-kernel@...r.kernel.org
Subject: Re: Allocating buffers for USB transfers (again)

On Thu, Jul 7, 2011 at 3:08 PM, Oliver Neukum <oliver@...kum.org> wrote:
> Am Donnerstag, 7. Juli 2011, 14:38:51 schrieb Daniel Mack:
>> On Thu, Jul 7, 2011 at 2:33 PM, Oliver Neukum <oliver@...kum.org> wrote:
>>
>> > PS:  Do you still see this if you enable 64bit DMA for EHCI?
>>
>> The problem is that I personally don't see that issue at all. I even
>> installed 4GB of RAM to my development machine last year to be able to
>> reproduce this, but I can't, even when the memory allocator is under
>> heavy load. The only people who see this effect are Pedro Ribeiro and
>> William Light (both in Cc:), and both have been very helpful in trying
>> patches and reporting back in detail. Which instructions could we
>> probably give to these people to finally hunt this issue down?
>
> Do they have an IOMMU or are they using bounce buffers?
> If the latter, you might be able to reproduce it if you disable your
> IOMMU.

Ok, Pedro and William - can I ask you to dump the following
information to some paste bin:

- your .config
- the dmesg output of a booted kernel that shows the effect
- the output of "sudo lspci -v"

Also, the attached patch might give you at least one warning to your
kernel logs once the audio stream starts and outputs noise. I'm
curious whether it really does.

Thanks,
Daniel

View attachment "ehci-32bit-debug.diff" of type "text/x-patch" (605 bytes)