Re: Race condition while using usbnet with NM 0.7.1

[Ricardo Salveti de Araujo <ricardo salveti openbossa org>]

On Mon, Jul 13, 2009 at 8:44 PM, Dan Williams<dcbw redhat com> wrote:
> On Fri, 2009-07-10 at 20:32 -0300, Ricardo Salveti de Araujo wrote:
>> Hi all,
>>
>> We're currently using Network Manager at Mamona, a developer distro
>> based on open embedded for Nokia tablet devices.
>>
>> Currently we're using NM 0.7 and we just created the packages for NM
>> 0.7.1, but while testing it, I faced some race condition issues with
>> the usbnet.
>
> Ha!  I've been looking for that race off and on for a while.  Thanks for
> finding the root cause.  Can you try out this commit from master?  If it
> works for you I'll also cherry-pick to 0.7.x.
>
> commit 302c9fcbccf3ad945afbc3f58e42013045c6e352
> Author: Dan Williams <dcbw redhat com>
> Date:   Mon Jul 13 19:40:39 2009 -0400
>
>    netlink: fix race that caused stale carrier state signals
>
>    Found by Ricardo Salveti de Araujo <ricardo salveti openbossa org>
>
>    The link cache was updated immediately, but the carrier state signals
>    were emitted a lot later, when the cache data was already stale.  So
>    just update the cache at the same time we emit the signals.  The
>    carrier-state-request stuff wasn't originally converted to deferred
>    for any netlink-specific reason, just to smooth the initial device
>    creation process in NM.

Cool, just tested the patch at NM 0.7.1 and it's now working as expected.

I was using a much similar patch (just cosmetic differences), so I can
confirm that this actually fix the issue.

Thanks a lot!

Cheers,
-- 
Ricardo Salveti de Araujo