Thomas Gleixner 6d83f94db9 genirq: Disable the SHIRQ_DEBUG call in request_threaded_irq for now ... With CONFIG_SHIRQ_DEBUG=y we call a newly installed interrupt handler in request_threaded_irq(). The original implementation (commit a304e1b8) called the handler _BEFORE_ it was installed, but that caused problems with handlers calling disable_irq_nosync(). See commit 377bf1e4. It's braindead in the first place to call disable_irq_nosync in shared handlers, but .... Moving this call after we installed the handler looks innocent, but it is very subtle broken on SMP. Interrupt handlers rely on the fact, that the irq core prevents reentrancy. Now this debug call violates that promise because we run the handler w/o the IRQ_INPROGRESS protection - which we cannot apply here because that would result in a possibly forever masked interrupt line. A concurrent real hardware interrupt on a different CPU results in handler reentrancy and can lead to complete wreckage, which was unfortunately observed in reality and took a fricking long time to debug. Leave the code here for now. We want this debug feature, but that's not easy to fix. We really should get rid of those disable_irq_nosync() abusers and remove that function completely. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Anton Vorontsov <avorontsov@ru.mvista.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: stable@kernel.org # .28 -> .37		2011-02-19 12:11:13 +01:00
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autoprobe.c	genirq: Provide compat handling for chip->set_type()	2010-10-04 12:43:47 +02:00
chip.c	genirq: Sanitize dynamic irq handling	2010-10-12 16:53:44 +02:00
devres.c	devres/irq: Fix devm_irq_match comment	2010-02-11 16:01:02 +01:00
dummychip.c	genirq: Fix CONFIG_GENIRQ_NO_DEPRECATED=y build	2010-10-12 21:59:55 +02:00
handle.c	genirq: Remove __do_IRQ	2011-01-21 11:55:31 +01:00
internals.h	genirq: Prevent access beyond allocated_irqs bitmap	2011-02-19 12:10:51 +01:00
irqdesc.c	genirq: Prevent access beyond allocated_irqs bitmap	2011-02-19 12:10:51 +01:00
Kconfig	genirq: Remove __do_IRQ	2011-01-21 11:55:31 +01:00
Makefile	genirq: Remove the now unused sparse irq leftovers	2010-10-12 16:53:44 +02:00
manage.c	genirq: Disable the SHIRQ_DEBUG call in request_threaded_irq for now	2011-02-19 12:11:13 +01:00
migration.c	genirq: Prevent irq storm on migration	2011-02-02 22:15:08 +01:00
pm.c	genirq: Convert irq_desc.lock to raw_spinlock	2009-12-14 23:55:33 +01:00
proc.c	genirq: Fix incorrect proc spurious output	2010-12-01 08:44:26 +01:00
resend.c	genirq: Prevent access beyond allocated_irqs bitmap	2011-02-19 12:10:51 +01:00
spurious.c	genirq: Provide config option to disable deprecated code	2010-10-04 13:40:24 +02:00