lkml.org 
[lkml]   [2010]   [Sep]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 04/14] memstick: core: fix device_register() error handling
    On Wed, Sep 22, 2010 at 08:50 -0700, Greg KH wrote:
    > On Wed, Sep 22, 2010 at 10:53:21AM +0200, Kay Sievers wrote:
    > > On Wed, Sep 22, 2010 at 00:49, Greg KH <greg@kroah.com> wrote:
    > >
    > > >  int device_register(struct device *dev)
    > > >  {
    > > > +       int retval;
    > > > +
    > > >        device_initialize(dev);
    > > > -       return device_add(dev);
    > > > +       retval = device_add(dev);
    > > > +       if (retval)
    > > > +               put_device(dev);
    > > > +       return retval;
    > > >  }
    > >
    > > > Kay, what am I missing here, why can't we just do this?  Hm, the
    > > > side-affect might be that if device_register() fails, NO ONE had better
    > > > touch that device again, as it might have just been freed from the
    > > > system.  I wonder if that will cause problems...
    > >
    > > That looks right, besides that there might be callers already doing
    > > this. Which needs to be checked.
    >
    > Yes, it would be. I'll go through the tree.

    As I see with this in-device_register patch we should check for 2 things:

    1) nobody should call put_device() because of failed device_register().

    2) dev has to be already got, other words its ref counter should not be zero.

    Correct?

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

    \
     
     \ /
      Last update: 2010-09-27 20:09    [W:6.244 / U:0.032 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site