Re: root-owned /proc/pid files for threaded apps?

[Danek Duvall <duvall@emufarm.org>]

On Fri, Mar 08, 2002 at 10:29:42PM +0100, Andreas Ferber wrote:

> On Fri, Mar 08, 2002 at 12:31:57PM -0800, Danek Duvall wrote:
> 
> > So it also turns out that either by changing that argument to 0 or
> > just reverting that hunk of the patch, xmms starts skipping whenever
> > mozilla loads a page, even a really simple one.
> 
> ie. always when mozilla tries to do a socket(PF_INET6, ...), which
> ends up requesting the ipv6 module. 

I don't think so -- modprobe logs its attempts in /var/log/ksymoops/ and
there aren't nearly as many attempts to load net-pf-10 logged there as
pages I reloaded.

Besides if you were right, it would do the same thing in the unchanged
ac kernel -- try to load ipv6 each time and fail -- and I'd presumably
see the skipping there, too.

> > Disk activity and other network activity don't seem to cause the
> > skipping, and the skipping disappears when I go back to an unaltered
> > ac kernel, so there seems to be something wrong with set_user(0, 0)
> > as well, just a different problem.
> 
> Uhm, this one seems rather strange.

No argument from me.

> Maybe it's related to the wmb() done by set_user() if dumpclear is
> set? (although it's actually a nop on most x86 (which arch are you
> using?))

AMD K6-III, just to be specific.

> Just for testing, can you try moving the wmb() in set_user()
> (kernel/sys.c, line 512 in 2.4.19-pre2-ac3) out of the if statement?

I'd expect to see the skipping regardless, then, right?  I'll give it a
shot tonight and report back.

Thanks,
Danek