Re: must-fix list for 2.6.0

[Andrew Morton]

Christoph Hellwig <[e-mail]> wrote:
>
> drivers/scsi/
> 
>  - large parts of the locking are hosed or not existant
>       o shost->my_devices isn't locked down at all
>       o the host list ist locked but not refcounted, mess can
>          happen when the spinlock is dropped
>       o there are lots of members of struct Scsi_Host/scsi_device/scsi_cmnd
>         with very unclear locking, many of them probably want to become
> 	atomic_t's or bitmaps (for the 1bit bitfields).
>       o there's lots of volatile abuse in the scsi code that needs to
>         be thought about.
>       o there's some global variables incremented without any locks

Thanks.

> fs/devfs/
> 
>  - there's a fundamental lookup vs devfsd race that's only fixable
>    by introducing a lookup vs devfs deadlock.  I can't see how this
>    is fixable without getting rid of the current devfsd design.
>    Mandrake seems to have a workaround for this so this is at least
>    not triggered so easily, but that's not what I'd considere a fix..

Look.  Please.  If you have the time, let's just put it out of its misery.

I had two concerns with smalldevfs:

- It's dropping a semaphore (i_sem?) during its synchronous userspace
  callout.  That was for deadlock avoidance and may have introduced a race.

- The new userspace doesn't support the compatibility names.  Just some
  config file, or a tarball or a dang shell script full of `ln -s'
  calls would fix that up, I think.