linux/kernel/irq, branch v3.0.23

genirq: Handle pending irqs in irq_startup()

2012-03-01T00:34:29Z

commit b4bc724e82e80478cba5fe9825b62e71ddf78757 upstream. An interrupt might be pending when irq_startup() is called, but the startup code does not invoke the resend logic. In some cases this prevents the device from issuing another interrupt which renders the device non functional. Call the resend function in irq_startup() to keep things going. Reported-and-tested-by: Russell King Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

genirq: Unmask oneshot irqs when thread was not woken

2012-03-01T00:34:29Z

commit ac5637611150281f398bb7a47e3fcb69a09e7803 upstream. When the primary handler of an interrupt which is marked IRQ_ONESHOT returns IRQ_HANDLED or IRQ_NONE, then the interrupt thread is not woken and the unmask logic of the interrupt line is never invoked. This keeps the interrupt masked forever. This was not noticed as most IRQ_ONESHOT users wake the thread unconditionally (usually because they cannot access the underlying device from hard interrupt context). Though this behaviour was nowhere documented and not necessarily intentional. Some drivers can avoid the thread wakeup in certain cases and run into the situation where the interrupt line s kept masked. Handle it gracefully. Reported-and-tested-by: Lothar Wassmann Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

genirq: Fix race condition when stopping the irq thread

2011-12-09T16:52:46Z

commit 550acb19269d65f32e9ac4ddb26c2b2070e37f1c upstream. In irq_wait_for_interrupt(), the should_stop member is verified before setting the task's state to TASK_INTERRUPTIBLE and calling schedule(). In case kthread_stop sets should_stop and wakes up the process after should_stop is checked by the irq thread but before the task's state is changed, the irq thread might never exit: kthread_stop irq_wait_for_interrupt ------------ ---------------------- ... ... while (!kthread_should_stop()) { kthread->should_stop = 1; wake_up_process(k); wait_for_completion(&kthread->exited); ... set_current_state(TASK_INTERRUPTIBLE); ... schedule(); } Fix this by checking if the thread should stop after modifying the task's state. [ tglx: Simplified it a bit ] Signed-off-by: Ido Yariv Link: http://lkml.kernel.org/r/1322740508-22640-1-git-send-email-ido@wizery.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

genirq: fix regression in irqfixup, irqpoll

2011-12-09T16:52:27Z

commit 52553ddffad76ccf192d4dd9ce88d5818f57f62a upstream. Commit fa27271bc8d2("genirq: Fixup poll handling") introduced a regression that broke irqfixup/irqpoll for some hardware configurations. Amidst reorganizing 'try_one_irq', that patch removed a test that checked for 'action->handler' returning IRQ_HANDLED, before acting on the interrupt. Restoring this test back returns the functionality lost since 2.6.39. In the current set of tests, after 'action' is set, it must precede '!action->next' to take effect. With this and my previous patch to irq/spurious.c, c75d720fca8a, all IRQ regressions that I have encountered are fixed. Signed-off-by: Edward Donovan Reported-and-tested-by: Rogério Brito Cc: Thomas Gleixner Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

genirq: Fix irqfixup, irqpoll regression

2011-11-26T17:09:51Z

commit c75d720fca8a91ce99196d33adea383621027bf2 upstream. commit d05c65fff0 ("genirq: spurious: Run only one poller at a time") introduced a regression, leaving the boot options 'irqfixup' and 'irqpoll' non-functional. The patch placed tests in each function, to exit if the function is already running. The test in 'misrouted_irq' exited when it should have proceeded, effectively disabling 'misrouted_irq' and 'poll_spurious_irqs'. The check for an already running poller needs to be "!= 1" not "== 1" as "1" is the value when the first poller starts running. Signed-off-by: Edward Donovan Cc: maciej.rutecki@gmail.com Link: http://lkml.kernel.org/r/1320175784-6745-1-git-send-email-edward.donovan@numble.net Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

genirq: Add IRQF_RESUME_EARLY and resume such IRQs earlier

2011-11-11T17:35:54Z

commit 9bab0b7fbaceec47d32db51cd9e59c82fb071f5a upstream. This adds a mechanism to resume selected IRQs during syscore_resume instead of dpm_resume_noirq. Under Xen we need to resume IRQs associated with IPIs early enough that the resched IPI is unmasked and we can therefore schedule ourselves out of the stop_machine where the suspend/resume takes place. This issue was introduced by 676dc3cf5bc3 "xen: Use IRQF_FORCE_RESUME". Signed-off-by: Ian Campbell Cc: Rafael J. Wysocki Cc: Jeremy Fitzhardinge Cc: xen-devel Cc: Konrad Rzeszutek Wilk Link: http://lkml.kernel.org/r/1318713254.11016.52.camel@dagon.hellion.org.uk Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

genirq: Make irq_shutdown() symmetric vs. irq_startup again

2011-10-03T18:40:27Z

commit ed585a651681e822089087b426e6ebfb6d3d9873 upstream. If an irq_chip provides .irq_shutdown(), but neither of .irq_disable() or .irq_mask(), free_irq() crashes when jumping to NULL. Fix this by only trying .irq_disable() and .irq_mask() if there's no .irq_shutdown() provided. This revives the symmetry with irq_startup(), which tries .irq_startup(), .irq_enable(), and irq_unmask(), and makes it consistent with the comment for irq_chip.irq_shutdown() in , which says: * @irq_shutdown: shut down the interrupt (defaults to ->disable if NULL) This is also how __free_irq() behaved before the big overhaul, cfr. e.g. 3b56f0585fd4c02d047dc406668cb40159b2d340 ("genirq: Remove bogus conditional"), where the core interrupt code always overrode .irq_shutdown() to .irq_disable() if .irq_shutdown() was NULL. Signed-off-by: Geert Uytterhoeven Cc: linux-m68k@lists.linux-m68k.org Link: http://lkml.kernel.org/r/1315742394-16036-2-git-send-email-geert@linux-m68k.org Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

genirq: Fix wrong bit operation

2011-08-29T20:29:06Z

commit 1dd75f91ae713049eb6baaa640078f3a6549e522 upstream. (!msk & 0x01) should be !(msk & 0x01) Signed-off-by: Jonghwan Choi Link: http://lkml.kernel.org/r/1311229754-6003-1-git-send-email-jhbird.choi@samsung.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

genirq: replace irq_gc_ack() with {set,clr}_bit variants (fwd)

2011-07-07T16:02:26Z

This fixes a regression introduced by e59347a "arm: orion: Use generic irq chip". Depending on the device, interrupts acknowledgement is done by setting or by clearing a dedicated register. Replace irq_gc_ack() with some {set,clr}_bit variants allows to handle both cases. Note that this patch affects the following SoCs: Davinci, Samsung and Orion. Except for this last, the change is minor: irq_gc_ack() is just renamed into irq_gc_ack_set_bit(). For the Orion SoCs, the edge GPIO interrupts support is currently broken. irq_gc_ack() try to acknowledge a such interrupt by setting the corresponding cause register bit. The Orion GPIO device expect the opposite. To fix this issue, the irq_gc_ack_clr_bit() variant is used. Tested on Network Space v2. Reported-by: Joey Oravec Signed-off-by: Simon Guinot Signed-off-by: Arnd Bergmann

genirq: Prevent potential NULL dereference in irq_set_irq_wake()

2011-06-10T08:53:42Z

In kernel/irq/manage.c::irq_set_irq_wake() we call irq_get_desc_buslock() which may return NULL, but the code dereferences the result unconditionally. irq_set_irq_wake() has lots of callers - I checked a few and I couldn't find anything that guarantees that they won't call it with some input that will cause irq_get_desc_buslock() to return NULL, so I think it's a good thing to test and -EINVAL was the most sane error code in this situation that I could think of. Not all callers test the return value of irq_set_irq_wake(), but those that do take != 0 to mean error as far as I can see, so they should be fine. I guess those that don't test actually should, but that's a different issue. Signed-off-by: Jesper Juhl Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1106092300360.17868@swampdragon.chaosbits.net Signed-off-by: Thomas Gleixner