Re: [RESEND][PATCH] Bluetooth: Make request workqueue freezable

[Laura Abbott]

On 05/21/2015 11:11 AM, Takashi Iwai wrote:
> At Thu, 21 May 2015 13:37:56 -0400 (EDT),
> Alan Stern wrote:
> > On Thu, 21 May 2015, Takashi Iwai wrote:
> >
> > > At Thu, 21 May 2015 11:26:17 -0400 (EDT),
> > > Alan Stern wrote:
> > > > On Thu, 21 May 2015, Takashi Iwai wrote:
> > > >
> > > > > At Thu, 21 May 2015 10:18:08 -0400 (EDT),
> > > > > Alan Stern wrote:
> > > > > > On Thu, 21 May 2015, Takashi Iwai wrote:
> > > > > >
> > > > > > > Then avoiding the failed firmware is no solution, indeed.
> > > > > > > If it's a new probe, it should be never executed during resume.
> > > > > >
> > > > > > Can you expand this comment?  What's wrong with probing during resume?
> > > > >
> > > > > Well, if the probe requires the access to a user-space file, it can't
> > > > > be done during resume.  That's the very problem we're seeing now.
> > > > > The firmware loader can't help much alone if it's a new device
> > > > > object.
> > > >
> > > > But the same thing happens during early boot, if the driver is built
> > > > into the kernel.  When the probe occurs, userspace isn't up and running
> > > > yet, so the firmware loader can't do anything.
> > > >
> > > > Why should probe during resume be any worse than probe during early
> > > > boot?
> > >
> > > The early boot has initrd, so the files can be there.  But the resume
> > > has no way to fetch the file except for cached data.
> >
> > I suppose USB could delay re-probing until userspace is running again,
> > if we knew when that was.  But it would be awkward and prone to races.
> > It also would leave a user-visible window of time during which the
> > device does not exist, which we want to avoid.  (This may not matter
> > for bluetooth, but it does matter for other kinds of devices.)
>
> Right.
>
> > I would prefer to solve this problem in a different way, if possible.
>
> Well, we're back in square again :)
>
> But, before going further the discussion in loop again, I'd like to
> know which firmware file actually hits.  Is it a non-existing
> firmware?  Or is it a firmware that should have been cached?  In the
> latter case, why it isn't used?

Non-existent firmware. The firmware was never present in the system and
was never loaded at all.

> Takashi

Thanks,
Laura
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/