linux/kernel/irq, branch v4.2

genirq: Introduce irq_chip_set_type_parent() helper

2015-08-19T22:25:25Z

This helper is required for irq chips which do not implement a irq_set_type callback and need to call down the irq domain hierarchy for the actual trigger type change. This helper is required to fix further wreckage caused by the conversion of TI OMAP to hierarchical irq domains and therefor tagged for stable. [ tglx: Massaged changelog ] Signed-off-by: Grygorii Strashko Cc: Sudeep Holla Cc: Cc: Cc: Cc: Cc: Cc: Cc: Cc: stable@vger.kernel.org # 4.1 Link: http://lkml.kernel.org/r/1439554830-19502-3-git-send-email-grygorii.strashko@ti.com Signed-off-by: Thomas Gleixner

genirq: Don't return ENOSYS in irq_chip_retrigger_hierarchy

2015-08-19T22:25:25Z

irq_chip_retrigger_hierarchy() returns -ENOSYS if it was not able to find at least one .irq_retrigger() callback implemented in the IRQ domain hierarchy. That's wrong, because check_irq_resend() expects a 0 return value from the callback in case that the hardware assisted resend was not possible. If the return value is non zero the core code assumes hardware resend success and the software resend is not invoked. This results in lost interrupts on platforms where none of the parent irq chips in the hierarchy implements the retrigger callback. This is observable on TI OMAP, where the hierarchy is: ARM GIC <- OMAP wakeupgen <- TI Crossbar Return 0 instead so the software resend mechanism gets invoked. [ tglx: Massaged changelog ] Fixes: 85f08c17de26 ('genirq: Introduce helper functions...') Signed-off-by: Grygorii Strashko Reviewed-by: Marc Zyngier Reviewed-by: Jiang Liu Cc: Sudeep Holla Cc: Cc: Cc: Cc: Cc: Cc: Cc: stable@vger.kernel.org # 4.1 Link: http://lkml.kernel.org/r/1439554830-19502-2-git-send-email-grygorii.strashko@ti.com Signed-off-by: Thomas Gleixner

genirq: Prevent resend to interrupts marked IRQ_NESTED_THREAD

2015-07-17T09:29:34Z

The resend mechanism happily calls the interrupt handler of interrupts which are marked IRQ_NESTED_THREAD from softirq context. This can result in crashes because the interrupt handler is not the proper way to invoke the device handlers. They must be invoked via handle_nested_irq. Prevent the resend even if the interrupt has no valid parent irq set. Its better to have a lost interrupt than a crashing machine. Reported-by: Uwe Kleine-König Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org

hotplug: Prevent alloc/free of irq descriptors during cpu up/down

2015-07-08T09:32:25Z

When a cpu goes up some architectures (e.g. x86) have to walk the irq space to set up the vector space for the cpu. While this needs extra protection at the architecture level we can avoid a few race conditions by preventing the concurrent allocation/free of irq descriptors and the associated data. When a cpu goes down it moves the interrupts which are targeted to this cpu away by reassigning the affinities. While this happens interrupts can be allocated and freed, which opens a can of race conditions in the code which reassignes the affinities because interrupt descriptors might be freed underneath. Example: CPU1 CPU2 cpu_up/down irq_desc = irq_to_desc(irq); remove_from_radix_tree(desc); raw_spin_lock(&desc->lock); free(desc); We could protect the irq descriptors with RCU, but that would require a full tree change of all accesses to interrupt descriptors. But fortunately these kind of race conditions are rather limited to a few things like cpu hotplug. The normal setup/teardown is very well serialized. So the simpler and obvious solution is: Prevent allocation and freeing of interrupt descriptors accross cpu hotplug. Signed-off-by: Thomas Gleixner Acked-by: Peter Zijlstra Cc: xiao jin Cc: Joerg Roedel Cc: Borislav Petkov Cc: Yanmin Zhang Link: http://lkml.kernel.org/r/20150705171102.063519515@linutronix.de

Merge branch 'irq/for-x86' into irq/core

2015-06-20T17:14:31Z

Get the infrastructure patches which are required for x86/apic into core

genirq: Remove bogus restriction in irq_move_mask_irq()

2015-06-20T17:05:14Z

If an interrupt is marked with the no balancing flag, we still allow setting the affinity for such an interrupt from the kernel itself, but for interrupts which move the affinity from interrupt context via irq_move_mask_irq() this runs into a check for the no balancing flag, which in turn ends up with an endless storm of stack dumps because the move pending flag is not reset. Allow the move for interrupts which have the no balancing flag set and clear the move pending bit before checking for interrupts with the per cpu flag set. Reported-by: Sergey Senozhatsky Cc: Borislav Petkov Cc: Jiang Liu Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1506201002570.4107@nanos Signed-off-by: Thomas Gleixner

irq: Add irq_set_chained_handler_and_data()

2015-06-18T12:03:08Z

Driver authors seem to get the ordering of irq_set_chained_handler() and irq_set_handler_data() wrong - ordering the former before the latter. This opens a race window where, if there is an interrupt pending, the handler will be called between these two calls, potentially resulting in an oops. Provide a single interface to set both of these together, especially as that's commonly what is required. Signed-off-by: Russell King Cc: Alexandre Courbot Cc: Hans Ulli Kroll Cc: Jason Cooper Cc: Lee Jones Cc: Linus Walleij Cc: Thierry Reding Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/E1Z4yzs-0002Rw-4B@rmk-PC.arm.linux.org.uk Signed-off-by: Thomas Gleixner

genirq: Introduce helper function irq_data_get_node()

2015-06-12T14:54:21Z

Introduce helper function irq_data_get_node() and variants thereof to hide struct irq_data implementation details. Convert the core code to use them. Signed-off-by: Jiang Liu Cc: Konrad Rzeszutek Wilk Cc: Tony Luck Cc: Bjorn Helgaas Cc: Benjamin Herrenschmidt Cc: Randy Dunlap Cc: Yinghai Lu Cc: Borislav Petkov Cc: Jason Cooper Cc: Kevin Cernekee Cc: Arnd Bergmann Link: http://lkml.kernel.org/r/1433145945-789-5-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner

genirq: Introduce struct irq_common_data to host shared irq data

2015-06-12T14:54:21Z

With the introduction of hierarchy irqdomain, struct irq_data becomes per-chip instead of per-irq and there may be multiple irq_datas associated with the same irq. Some per-irq data stored in struct irq_data now may get duplicated into multiple irq_datas, and causes inconsistent view. So introduce struct irq_common_data to host per-irq common data and to achieve consistent view among irq_chips. Signed-off-by: Jiang Liu Cc: Konrad Rzeszutek Wilk Cc: Tony Luck Cc: Bjorn Helgaas Cc: Benjamin Herrenschmidt Cc: Randy Dunlap Cc: Yinghai Lu Cc: Borislav Petkov Cc: Jason Cooper Cc: Kevin Cernekee Cc: Arnd Bergmann Cc: Marc Zyngier Link: http://lkml.kernel.org/r/1433145945-789-4-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner

genirq: Prevent crash in irq_move_irq()

2015-06-12T14:54:21Z

The functions irq_move_irq() and irq_move_masked_irq() expect that the caller passes the top-level irq_data to them when hierarchical irqdomains are enabled. But that's not true when called from apic_ack_edge(), which results in a null pointer dereference by idata->chip->irq_mask(idata). Instead of fixing callers to passing top-level irq_data, we rather change irq_move_irq()/irq_move_masked_irq() to accept any irq_data. Signed-off-by: Jiang Liu Cc: Konrad Rzeszutek Wilk Cc: Tony Luck Cc: Bjorn Helgaas Cc: Benjamin Herrenschmidt Cc: Randy Dunlap Cc: Yinghai Lu Cc: Borislav Petkov Link: http://lkml.kernel.org/r/1433145945-789-3-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner