Re: Analyzed/Solved: Booting 2.6.30-rc2-git7 very slow

[Andrew Morton]

On Wed, 29 Apr 2009 16:18:45 +0200
Mike Galbraith <efault@xxxxxx> wrote:

> On Wed, 2009-04-29 at 13:08 +0100, Al Viro wrote:
> > On Wed, Apr 29, 2009 at 01:17:55AM -0700, Andrew Morton wrote:
> > 
> > > > > > Questions remains: was this intentional? It breaks existing userspace and should therefore be considered a regression - right? On the other hand, it will never be a problem for RHEL-4/5 kernels, unless the change in 2.6.29 gets backported. Any ideas?
> > > > > 
> > > > > afaik that was unintentional and was probably a mistake.
> > > > > 
> > > > > I wonder how we did that.
> > > > 
> > > > <paste>
> > > > > [hotplug]# grep sysfs /proc/mounts
> > > > > none /sys sysfs rw,relatime 0 0
> > > > > /sys /sys sysfs rw,relatime 0 0
> > > > 
> > > > ___(I wonder how the heck that is accomplished)
> > > 
> > > Beats me.  I'm not seeing likely changes in fs/proc/base.c or around
> > > show_mountinfo().  Maybe sysfs broke in an ingenious way.  (hopefully
> > > cc's viro).
> > 
> > Er...  Somebody mounting sysfs twice?  From some init script and from
> > /etc/fstab, perhaps?  That definitely looks like two mount(2) had to
> > have been done to cause that...
> 
> Yeah, but how does one go about doing that?
> 
> Using mount -f, I can convince mount to succeed, but I still have only
> one entry in /proc/mounts, despite what my mount binary imagines.
> 
> marge:..sys/vm # grep sysfs /proc/mounts
> sysfs /sys sysfs rw,relatime 0 0
> 
> marge:..sys/vm # mount|grep sysfs
> sysfs on /sys type sysfs (rw)
> sys on /sys type sysfs (rw)
> /sys on /sys type sysfs (rw)
> 

So /proc/mounts is OK and /etc/mtab is wrong?

Obvious next step is to strace `mount -f', see what's happening around
sys_mount(), please.

--
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/