Use of CONFIG_PROVE_LOCKING With RT patch

Use of CONFIG_PROVE_LOCKING With RT patch

[David Peverley]

Hi all,

I'm working with (a modified) linux-2.6.31.12-rt21 and have been
trying to enable CONFIG_PROVE_LOCKING but for my build this
comepletely stops the kernel coming up. Doing a bit of reading through
the config, it seems that when I select PROVE_LOCKING my .config has
the following added :
  CONFIG_DEBUG_MUTEXES=y
  CONFIG_DEBUG_LOCK_ALLOC=y
  CONFIG_PROVE_LOCKING=y
  CONFIG_LOCKDEP=y
  CONFIG_TRACE_IRQFLAGS=y

So one of them is likely to be the individual cause. However, reading
through the config I'm confused... If you read lib/Kconfig.debug you
see that DEBUG_LOCK_ALLOC selects DEBUG_MUTEXES. However DEBUG_MUTEXES
has :
        depends on DEBUG_KERNEL && !PREEMPT_RT
BUT this kernel has PREEMPT_RT set.... Should the config system have
actually set it? The real question of course is that if
CONFIG_DEBUG_MUTEXES shouldn't be included for a PREEMPT_RT kernel,
could this be part of the issue I'm seeing, i.e. its causing the
lockup?

Cheers,

~Pev