[PATCH] Fix bug #13121 - Non-smbd processes using kernel oplocks can hang smbd

[Andreas Schneider]

On Wednesday, 15 November 2017 19:52:18 CET Jeremy Allison via samba-technical 
wrote:
> On Wed, Nov 15, 2017 at 10:06:01AM -0800, Jeremy Allison via samba-technical 
wrote:
> > On Thu, Nov 16, 2017 at 06:55:13AM +1300, Gary Lockyer via samba-technical 
wrote:
> > > I'm now seeing significant numbers of builds hanging in:
> > > 
> > > [558(3538)/2212 at 1h13m33s] samba3.smb2.kernel-oplocks(nt4_dc)
> > 
> > Can you track down what part of the test it's hanging in ?
> > A strace on the smbtorture client process would help here.
> > 
> > The test does depend on working kernel oplocks as the
> > test child holds the lease for 3 seconds. Also, the
> > child does a pause() waiting for a signal which is
> > expected to come when the smbd tries to open the leased
> > file. I could add a 5 second alarm() timeout to ensure
> > it can't ever hang there but under normal circumstances
> > it shouldn't hang.
> > 
> > What platform are you testing on - if it's non-Linux
> > this test should not be running.
> > 
> > I do want to keep this test if I can as it's a guarantee that
> > kernel oplocks are working correctly in smbd.
> 
> Can you try running your builds with this additional
> patch ?
> 
> It should prevent hangs from the smbtorture child using
> the alarm mechanism I mentioned above, and also if the
> test then fails it should print out a meaningful error
> code so we can discover where the child had problems.
> 
> Cheers,
> 
> 	Jeremy.

RB+

-- 
Andreas Schneider                   GPG-ID: CC014E3D
Samba Team                             asn at samba.org
www.samba.org