Re: Badness at mm/backing-dev.c:179

From: Geert Uytterhoeven
Date: Mon Dec 08 2008 - 07:54:59 EST


On Mon, 8 Dec 2008, Kay Sievers wrote:
> On Mon, Dec 8, 2008 at 09:16, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
> > On Wed, 3 Dec 2008, Kay Sievers wrote:
> >> On Wed, Dec 3, 2008 at 13:07, Mark Jackson <mpfj@xxxxxxxxxx> wrote:
> >> > The following commit causes a "Badness at mm/backing-dev.c:179":-
> >> >
> >> > f1d0b063d993527754f062c589b73f125024d216 is first bad commit
> >> > commit f1d0b063d993527754f062c589b73f125024d216
> >> > Author: Kay Sievers <kay.sievers@xxxxxxxx>
> >> > Date: Tue Dec 2 10:31:50 2008 -0800
> >> >
> >> > bdi: register sysfs bdi device only once per queue
> >>
> >> > Below is the extract from dmesg:-
> >> >
> >> > ------------[ cut here ]------------
> >> > Badness at mm/backing-dev.c:179
> >>
> >> That's a known issue, and will not cause any harm besides printing
> >> this warning. Andrew added the warning to catch drivers who use one
> >> single request queue for multiple devices. Currently known are mtd and
> >> floppy (triggers only if you have more than one device per driver).
> >> The drivers need to be changed to use a separate queue per device, to
> >> get rid of this warning.
> >
> > I guess this one (introduced after 2.6.28-rc7) is an incarnation of the same
> > issue?
>
> You have more than one floppy device registered at the same time,
> right? Then it's very likely the same issue, that both devices share
> the same request queue, like the x86 floppy.c.

Yep, ataflop.c (and amiflop.c) forked from floppy.c a long time ago...

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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