Re: Page allocation failure (order 7) in UAS code

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 04-03-16 08:13, Yves-Alexis Perez wrote:
> On mar., 2016-03-01 at 11:49 +0100, Hans de Goede wrote:
>> Hi,
>>
>> On 01-03-16 10:42, Yves-Alexis Perez wrote:
>>>
>>> Hi,
>>>
>>> [sorry if this is not the right point for reporting bugs, I took the email
>>> addresses from MAINTAINERS but please point me to the correct place if
>>> needed]
>>>
>>> I have an external USB drive (Samsung M3), which apparently uses the UAS
>>> code.
>>> Starting with 4.4 (from Debian sid, I could retry with vanilla if needed),
>>> I
>>> can't mount the drive anymore after a while (few hours/days uptime). Just
>>> plugging the disk, I get page allocation failure in kernel logs:
>> Can you try building a kernel with the following line in
>> drivers/usb/storage/uas.c :
>>
>>           .can_queue = 65536,     /* Is there a limit on the _host_ ? */
>>
>> (around line 815) Replaced with
>>
>>           .can_queue = MAX_CMNDS,
>>
>> That should help as MAX_CMNDS is 256, so claiming that we can queue more
>> is not helpful, and that likely is what is causing this quite high order
>> alloc.
>
> After a few days, it seems that it does work fine, although I can't say
> anything about sides effects.

Thanks for testing, there shouldn't be any side-effects, I'll turn this into
a proper patch, add a:

Reported-and-tested-by: Yves-Alexis Perez <corsac@corsac.net>

line to the comit msg and submit this upstream.

Regards,

Hans