linux/include
Thomas Gleixner 1e77d0a1ed genirq: Sanitize spurious interrupt detection of threaded irqs
Till reported that the spurious interrupt detection of threaded
interrupts is broken in two ways:

- note_interrupt() is called for each action thread of a shared
  interrupt line. That's wrong as we are only interested whether none
  of the device drivers felt responsible for the interrupt, but by
  calling multiple times for a single interrupt line we account
  IRQ_NONE even if one of the drivers felt responsible.

- note_interrupt() when called from the thread handler is not
  serialized. That leaves the members of irq_desc which are used for
  the spurious detection unprotected.

To solve this we need to defer the spurious detection of a threaded
interrupt to the next hardware interrupt context where we have
implicit serialization.

If note_interrupt is called with action_ret == IRQ_WAKE_THREAD, we
check whether the previous interrupt requested a deferred check. If
not, we request a deferred check for the next hardware interrupt and
return. 

If set, we check whether one of the interrupt threads signaled
success. Depending on this information we feed the result into the
spurious detector.

If one primary handler of a shared interrupt returns IRQ_HANDLED we
disable the deferred check of irq threads on the same line, as we have
found at least one device driver who cared.

Reported-by: Till Straumann <strauman@slac.stanford.edu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Austin Schuh <austin@peloton-tech.com>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: linux-can@vger.kernel.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1303071450130.22263@ionos
2014-05-03 23:15:39 +02:00
..
acpi IOMMU Upates for Linux v3.15 2014-04-05 18:46:26 -07:00
asm-generic word-at-a-time: simplify big-endian zero_bytemask macro 2014-05-01 08:57:44 -07:00
clocksource
crypto crypto: export NULL algorithms defines 2014-03-21 21:54:26 +08:00
drm Merge branch 'drm-next-3.15-wip' of git://people.freedesktop.org/~deathsimple/linux into drm-next 2014-04-19 11:16:02 +10:00
dt-bindings dt: tegra: remove non-existent clock IDs 2014-04-24 15:37:08 +02:00
keys
kvm
linux genirq: Sanitize spurious interrupt detection of threaded irqs 2014-05-03 23:15:39 +02:00
math-emu
media [media] rc-core: remove generic scancode filter 2014-04-06 11:30:29 -03:00
memory
misc
net net: sctp: cache auth_enable per endpoint 2014-04-18 18:32:00 -04:00
pcmcia
ras
rdma Merge branches 'core', 'cxgb4', 'ip-roce', 'iser', 'misc', 'mlx4', 'nes', 'ocrdma', 'qib', 'sgwrapper', 'srp' and 'usnic' into for-next 2014-04-03 08:30:17 -07:00
rxrpc
scsi scsi: Make sure cmd_flags are 64-bit 2014-04-09 20:26:20 -06:00
sound ALSA: cs8427: separate HW initialization 2014-04-03 14:59:48 +02:00
target target/sbc: Add sbc_dif_read_strip software emulation 2014-04-07 01:48:57 -07:00
trace Fix: tracing: use 'E' instead of 'X' for unsigned module tain flag 2014-04-23 13:56:51 +09:30
uapi File locking related bugfixes for v3.15 (pile #2) 2014-04-25 12:40:32 -07:00
video fbdev changes for 3.15 (OMAP) 2014-04-07 10:47:51 -07:00
xen xen/acpi-processor: fix enabling interrupts on syscore_resume 2014-03-18 14:40:20 +00:00
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