kernel_optimize_test/kernel/irq
Thomas Gleixner 4001d8e876 genirq: Delay deactivation in free_irq()
When interrupts are shutdown, they are immediately deactivated in the
irqdomain hierarchy. While this looks obviously correct there is a subtle
issue:

There might be an interrupt in flight when free_irq() is invoking the
shutdown. This is properly handled at the irq descriptor / primary handler
level, but the deactivation might completely disable resources which are
required to acknowledge the interrupt.

Split the shutdown code and deactivate the interrupt after synchronization
in free_irq(). Fixup all other usage sites where this is not an issue to
invoke the combined shutdown_and_deactivate() function instead.

This still might be an issue if the interrupt in flight servicing is
delayed on a remote CPU beyond the invocation of synchronize_irq(), but
that cannot be handled at that level and needs to be handled in the
synchronize_irq() context.

Fixes: f8264e3496 ("irqdomain: Introduce new interfaces to support hierarchy irqdomains")
Reported-by: Robert Hodaszi <Robert.Hodaszi@digi.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/20190628111440.098196390@linutronix.de
2019-07-03 10:12:28 +02:00
..
affinity.c genirq/affinity: Remove the leftovers of the original set support 2019-02-18 11:21:29 +01:00
autoprobe.c genirq: Delay deactivation in free_irq() 2019-07-03 10:12:28 +02:00
chip.c genirq: Delay deactivation in free_irq() 2019-07-03 10:12:28 +02:00
cpuhotplug.c genirq: Delay deactivation in free_irq() 2019-07-03 10:12:28 +02:00
debug.h
debugfs.c irqchip updates for Linux 5.1 2019-02-23 10:53:31 +01:00
devres.c genirq/devres: Use struct_size() in devm_kzalloc() 2019-04-16 21:54:03 +02:00
dummychip.c
generic-chip.c
handle.c genirq: Correctly annotate implicit fall through 2019-01-15 10:40:53 +01:00
internals.h genirq: Delay deactivation in free_irq() 2019-07-03 10:12:28 +02:00
ipi.c genirq: Fix various typos in comments 2018-12-18 14:22:28 +01:00
irq_sim.c irq/irq_sim: add irq_set_type() callback 2019-02-19 17:42:28 +01:00
irqdesc.c genirq: Initialize request_mutex if CONFIG_SPARSE_IRQ=n 2019-04-05 14:37:56 +02:00
irqdomain.c This is the bulk of GPIO changes for the v5.1 cycle: 2019-03-08 10:09:53 -08:00
Kconfig genirq/irqchip: Remove MULTI_IRQ_HANDLER as it's now obselete 2018-08-03 12:14:10 +02:00
Makefile
manage.c genirq: Delay deactivation in free_irq() 2019-07-03 10:12:28 +02:00
matrix.c genirq/matrix: Improve target CPU selection for managed interrupts. 2018-11-06 23:20:13 +01:00
migration.c genirq/migration: Avoid out of line call if pending is not set 2018-06-06 15:18:20 +02:00
msi.c genirq/core: Introduce struct irq_affinity_desc 2018-12-19 11:32:08 +01:00
pm.c
proc.c genirq: Speedup show_interrupts() 2018-06-22 14:22:58 +02:00
resend.c
settings.h
spurious.c genirq: Fix various typos in comments 2018-12-18 14:22:28 +01:00
timings.c genirq/timings: Add array suffix computation code 2019-04-05 22:51:29 +02:00