user/sven/linux.git/kernel/irq, branch v3.2.55

irq: Enable all irqs unconditionally in irq_resume

2014-01-03T04:33:25Z

commit ac01810c9d2814238f08a227062e66a35a0e1ea2 upstream. When the system enters suspend, it disables all interrupts in suspend_device_irqs(), including the interrupts marked EARLY_RESUME. On the resume side things are different. The EARLY_RESUME interrupts are reenabled in sys_core_ops->resume and the non EARLY_RESUME interrupts are reenabled in the normal system resume path. When suspend_noirq() failed or suspend is aborted for any other reason, we might omit the resume side call to sys_core_ops->resume() and therefor the interrupts marked EARLY_RESUME are not reenabled and stay disabled forever. To solve this, enable all irqs unconditionally in irq_resume() regardless whether interrupts marked EARLY_RESUMEhave been already enabled or not. This might try to reenable already enabled interrupts in the non failure case, but the only affected platform is XEN and it has been confirmed that it does not cause any side effects. [ tglx: Massaged changelog. ] Signed-off-by: Laxman Dewangan Acked-by-and-tested-by: Konrad Rzeszutek Wilk Acked-by: Heiko Stuebner Reviewed-by: Pavel Machek Cc: Cc: Cc: Cc: Link: http://lkml.kernel.org/r/1385388587-16442-1-git-send-email-ldewangan@nvidia.com Signed-off-by: Thomas Gleixner Signed-off-by: Ben Hutchings

genirq: Fix can_request_irq() for IRQs without an action

2013-07-27T04:34:21Z

commit 2779db8d37d4b542d9ca2575f5f178dbeaca6c86 upstream. Commit 02725e7471b8 ('genirq: Use irq_get/put functions'), inadvertently changed can_request_irq() to return 0 for IRQs that have no action. This causes pcibios_lookup_irq() to select only IRQs that already have an action with IRQF_SHARED set, or to fail if there are none. Change can_request_irq() to return 1 for IRQs that have no action (if the first two conditions are met). Reported-by: Bjarni Ingi Gislason Tested-by: Bjarni Ingi Gislason (against 3.2) Signed-off-by: Ben Hutchings Cc: 709647@bugs.debian.org Link: http://bugs.debian.org/709647 Link: http://lkml.kernel.org/r/1372383630.23847.40.camel@deadeye.wl.decadent.org.uk Signed-off-by: Thomas Gleixner

genirq: Avoid deadlock in spurious handling

2013-03-06T03:22:34Z

commit e716efde75267eab919cdb2bef5b2cb77f305326 upstream. commit 52553ddf(genirq: fix regression in irqfixup, irqpoll) introduced a potential deadlock by calling the action handler with the irq descriptor lock held. Remove the call and let the handling code run even for an interrupt where only a single action is registered. That matches the goal of the above commit and avoids the deadlock. Document the confusing action = desc->action reload in the handling loop while at it. Reported-and-tested-by: "Wang, Warner" Tested-by: Edward Donovan Cc: "Wang, Song-Bo (Stoney)" Signed-off-by: Thomas Gleixner Signed-off-by: Ben Hutchings

genirq: Always force thread affinity

2013-01-03T03:33:05Z

commit 04aa530ec04f61875b99c12721162e2964e3318c upstream. Sankara reported that the genirq core code fails to adjust the affinity of an interrupt thread in several cases: 1) On request/setup_irq() the call to setup_affinity() happens before the new action is registered, so the new thread is not notified. 2) For secondary shared interrupts nothing notifies the new thread to change its affinity. 3) Interrupts which have the IRQ_NO_BALANCE flag set are not moving the thread either. Fix this by setting the thread affinity flag right on thread creation time. This ensures that under all circumstances the thread moves to the right place. Requires a check in irq_thread_check_affinity for an existing affinity mask (CONFIG_CPU_MASK_OFFSTACK=y) Reported-and-tested-by: Sankara Muthukrishnan Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1209041738200.2754@ionos Signed-off-by: Thomas Gleixner Signed-off-by: Ben Hutchings

random: make 'add_interrupt_randomness()' do something sane

2012-08-09T23:24:41Z

commit 775f4b297b780601e61787b766f306ed3e1d23eb upstream. We've been moving away from add_interrupt_randomness() for various reasons: it's too expensive to do on every interrupt, and flooding the CPU with interrupts could theoretically cause bogus floods of entropy from a somewhat externally controllable source. This solves both problems by limiting the actual randomness addition to just once a second or after 64 interrupts, whicever comes first. During that time, the interrupt cycle data is buffered up in a per-cpu pool. Also, we make sure the the nonblocking pool used by urandom is initialized before we start feeding the normal input pool. This assures that /dev/urandom is returning unpredictable data as soon as possible. (Based on an original patch by Linus, but significantly modified by tytso.) Tested-by: Eric Wustrow Reported-by: Eric Wustrow Reported-by: Nadia Heninger Reported-by: Zakir Durumeric Reported-by: J. Alex Halderman . Signed-off-by: Linus Torvalds Signed-off-by: "Theodore Ts'o" Signed-off-by: Ben Hutchings

genirq: Adjust irq thread affinity on IRQ_SET_MASK_OK_NOCOPY return value

2012-04-13T15:33:46Z

commit f5cb92ac82d06cb583c1f66666314c5c0a4d7913 upstream. irq_move_masked_irq() checks the return code of chip->irq_set_affinity() only for 0, but IRQ_SET_MASK_OK_NOCOPY is also a valid return code, which is there to avoid a redundant copy of the cpumask. But in case of IRQ_SET_MASK_OK_NOCOPY we not only avoid the redundant copy, we also fail to adjust the thread affinity of an eventually threaded interrupt handler. Handle IRQ_SET_MASK_OK (==0) and IRQ_SET_MASK_OK_NOCOPY(==1) return values correctly by checking the valid return values seperately. Signed-off-by: Jiang Liu Cc: Jiang Liu Cc: Keping Chen Link: http://lkml.kernel.org/r/1333120296-13563-2-git-send-email-jiang.liu@huawei.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

genirq: Fix incorrect check for forced IRQ thread handler

2012-04-02T16:52:35Z

commit 540b60e24f3f4781d80e47122f0c4486a03375b8 upstream. We do not want a bitwise AND between boolean operands Signed-off-by: Alexander Gordeev Cc: Oleg Nesterov Link: http://lkml.kernel.org/r/20120309135912.GA2114@dhcp-26-207.brq.redhat.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

genirq: Fix long-term regression in genirq irq_set_irq_type() handling

2012-04-02T16:52:35Z

commit a09b659cd68c10ec6a30cb91ebd2c327fcd5bfe5 upstream. In 2008, commit 0c5d1eb77a8be ("genirq: record trigger type") modified the way set_irq_type() handles the 'no trigger' condition. However, this has an adverse effect on PCMCIA support on Intel StrongARM and probably PXA platforms. PCMCIA has several status signals on the socket which can trigger interrupts; some of these status signals depend on the card's mode (whether it is configured in memory or IO mode). For example, cards have a 'Ready/IRQ' signal: in memory mode, this provides an indication to PCMCIA that the card has finished its power up initialization. In IO mode, it provides the device interrupt signal. Other status signals switch between on-board battery status and loud speaker output. In classical PCMCIA implementations, where you have a specific socket controller, the controller provides a method to mask interrupts from the socket, and importantly ignore any state transitions on the pins which correspond with interrupts once masked. This masking prevents unwanted events caused by the removal and application of socket power being forwarded. However, on platforms where there is no socket controller, the PCMCIA status and interrupt signals are routed to standard edge-triggered GPIOs. These GPIOs can be configured to interrupt on rising edge, falling edge, or never. This is where the problems start. Edge triggered interrupts are required to record events while disabled via the usual methods of {free,request,disable,enable}_irq() to prevent problems with dropped interrupts (eg, the 8390 driver uses disable_irq() to defer the delivery of interrupts). As a result, these interfaces can not be used to implement the desired behaviour. The side effect of this is that if the 'Ready/IRQ' GPIO is disabled via disable_irq() on suspend, and enabled via enable_irq() after resume, we will record the state transitions caused by powering events as valid interrupts, and foward them to the card driver, which may attempt to access a card which is not powered up. This leads delays resume while drivers spin in their interrupt handlers, and complaints from drivers before they realize what's happened. Moreover, in the case of the 'Ready/IRQ' signal, this is requested and freed by the card driver itself; the PCMCIA core has no idea whether the interrupt is requested, and, therefore, whether a call to disable_irq() would be valid. (We tried this around 2.4.17 / 2.5.1 kernel era, and ended up throwing it out because of this problem.) Therefore, it was decided back in around 2002 to disable the edge triggering instead, resulting in all state transitions on the GPIO being ignored. That's what we actually need the hardware to do. The commit above changes this behaviour; it explicitly prevents the 'no trigger' state being selected. The reason that request_irq() does not accept the 'no trigger' state is for compatibility with existing drivers which do not provide their desired triggering configuration. The set_irq_type() function is 'new' and not used by non-trigger aware drivers. Therefore, revert this change, and restore previously working platforms back to their former state. Signed-off-by: Russell King Cc: linux@arm.linux.org.uk Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

genirq: Clear action->thread_mask if IRQ_ONESHOT is not set

2012-03-12T19:31:24Z

commit 52abb700e16a9aa4cbc03f3d7f80206cbbc80680 upstream. Xommit ac5637611(genirq: Unmask oneshot irqs when thread was not woken) fails to unmask when a !IRQ_ONESHOT threaded handler is handled by handle_level_irq. This happens because thread_mask is or'ed unconditionally in irq_wake_thread(), but for !IRQ_ONESHOT interrupts never cleared. So the check for !desc->thread_active fails and keeps the interrupt disabled. Keep the thread_mask zero for !IRQ_ONESHOT interrupts. Document the thread_mask magic while at it. Reported-and-tested-by: Sven Joachim Reported-and-tested-by: Stefan Lippers-Hollmann Signed-off-by: Thomas Gleixner Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

genirq: Handle pending irqs in irq_startup()

2012-03-01T00:31:17Z

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