commit 91150af3a (powerpc/eeh: Fix unbalanced enable for IRQ) is
another brilliant example of trainwreck engineering.
The patch "fixes" the issue of an unbalanced call to irq_enable()
which causes a prominent warning by checking the disabled state of the
interrupt line and call conditionally into the core code.
This is wrong in two aspects:
1) The warning is there to tell users, that they need to fix their
asymetric enable/disable patterns by finding the root cause and
solving it there.
It's definitely not meant to work around it by conditionally
calling into the core code depending on the random state of the irq
line.
Asymetric irq_disable/enable calls are a clear sign of wrong usage
of the interfaces which have to be cured at the root and not by
somehow hacking around it.
2) The abuse of core internal data structure instead of using the
proper interfaces for retrieving the information for the 'hack
around'
irq_desc is core internal and it's clear enough stated.
Replace at least the irq_desc abuse with the proper functions and add
a big fat comment why this is absurd and completely wrong.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>
Link: http://lkml.kernel.org/r/20140223212736.562906212@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>