Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock()

!MAILaRCHIVE_VOTE_RePLACE
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
To: Peter Zijlstra <a.p.zijlstra@...>
Cc: Dave Jones <davej@...>, Roland Dreier <rdreier@...>, Linus Torvalds <torvalds@...>, David Miller <davem@...>, <jeremy@...>, <hugh@...>, <mingo@...>, <akpm@...>, <linux-kernel@...>
Date: Monday, August 4, 2008 - 1:27 pm

On Mon, Aug 04, 2008 at 06:38:55PM +0200, Peter Zijlstra wrote:

Sorry, that wasn't the problem, but my current testing passed because
of another error... to test this report I rebuilt a kvm configured for
rhel not for mainline so it wasn't the right test...

When "long ago" I tested that this was working fine (actually when
Andrew asked me), I guess lockdep was working because the
implementation with the vmalloc array was slightly different,
otherwise I don't know. I'm fairly certain that it worked fine at some
point, and I didn't expect the refactoring to generate false positives.


I can reproduce this now yes after a 'make sync'.

Obviously this is a bug in lockdep that it trips over this otherwise
if lockdep was right the kernel should deadlock while this is just a
false positive and everything runs fine.

I assume it can't understand the spinlock address is different (I
think it uses the address as key only for static locks), so I wonder
if you could call print_deadlock_bug() from the failure path of the
spinlock to solve this?

Do things like double_rq_lock works just because rq1 and rq2 don't
have the same name like in my case where all locks are called "mapping"->?


Woow cool, after 11 months I lost any hope that lockdep could ever
work in that environment... Was it an actual bug or is this some way
to lower the complexity of the graph build?
--
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]

Messages in current thread:
[RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Peter Zijlstra, (Mon Aug 4, 9:03 am)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Peter Zijlstra, (Thu Aug 7, 7:25 am)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Jeremy Fitzhardinge, (Mon Aug 4, 2:06 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Peter Zijlstra, (Mon Aug 4, 2:54 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Jeremy Fitzhardinge, (Mon Aug 4, 3:26 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Linus Torvalds, (Mon Aug 4, 3:31 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Steven Rostedt, (Wed Oct 8, 11:27 am)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Nick Piggin, (Wed Oct 8, 11:52 am)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Steven Rostedt, (Wed Oct 8, 1:18 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Linus Torvalds, (Wed Oct 8, 11:43 am)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Steven Rostedt, (Wed Oct 8, 12:03 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Linus Torvalds, (Wed Oct 8, 12:19 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Steven Rostedt, (Wed Oct 8, 12:53 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Jeremy Fitzhardinge, (Mon Aug 4, 4:16 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Peter Zijlstra, (Mon Aug 4, 3:39 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Roland Dreier, (Mon Aug 4, 10:07 am)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Peter Zijlstra, (Mon Aug 4, 10:19 am)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Roland Dreier, (Mon Aug 4, 10:26 am)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Peter Zijlstra, (Mon Aug 4, 10:32 am)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Dave Jones, (Mon Aug 4, 10:53 am)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Peter Zijlstra, (Mon Aug 4, 10:56 am)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Andrea Arcangeli, (Mon Aug 4, 12:26 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Peter Zijlstra, (Mon Aug 4, 12:38 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), David Miller, (Mon Aug 4, 5:32 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Andrea Arcangeli, (Mon Aug 4, 1:27 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Peter Zijlstra, (Mon Aug 4, 2:48 pm)
Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock(), Andrea Arcangeli, (Mon Aug 4, 1:46 pm)