set_type returns an int indicating success or failure, but up to now
setup_irq ignores that.
In my case this resulted in a machine hang:
gpio-keys requested IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, but
arm/ns9xxx can only trigger on one direction so set_type didn't touch
the configuration which happens do default to a level sensitiveness and
returned -EINVAL. setup_irq ignored that and unmasked the irq. This
resulted in an endless triggering of the gpio-key interrupt service
routine which effectively killed the machine.
With this patch applied setup_irq propagates the error to the caller.
Note that before in the case
chip && !chip->set_type && !chip->name
a NULL pointer was feed to printk. This is fixed, too.
Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Current IRQ affinity interface does not provide a way to set affinity
for the IRQs that will be allocated/activated in the future.
This patch creates /proc/irq/default_smp_affinity that lets users set
default affinity mask for the newly allocated IRQs. Changing the default
does not affect affinity masks for the currently active IRQs, they
have to be changed explicitly.
Updated based on Paul J's comments and added some more documentation.
Signed-off-by: Max Krasnyansky <maxk@qualcomm.com>
Cc: pj@sgi.com
Cc: a.p.zijlstra@chello.nl
Cc: tglx@linutronix.de
Cc: rdunlap@xenotime.net
Cc: mingo@elte.hu
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Uwe Kleine-Koenig has some strange hardware where one of the shared
interrupts can be asserted during boot before the appropriate driver
loads. Requesting the shared irq line from another driver result in a
spurious interrupt storm which finally disables the interrupt line.
I have seen similar behaviour on resume before (the hardware does not
work anymore so I can not verify).
Change the spurious disable logic to increment the disable depth and
mark the interrupt with an extra flag which allows us to reenable the
interrupt when a new driver arrives which requests the same irq
line. In the worst case this will disable the irq again via the
spurious trap, but there is a decent chance that the new driver is the
one which can handle the already asserted interrupt and makes the box
usable again.
Eric Biederman said further: This case also happens on a regular basis
in kdump kernels where we deliberately don't shutdown the hardware
before starting the new kernel. This patch should reduce the need for
using irqpoll in that situation by a small amount.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-and-Acked-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Following an experimental deletion of the unnecessary directive
#include <linux/slab.h>
from the header file <linux/percpu.h>, these files under kernel/ were exposed
as needing to include one of <linux/slab.h> or <linux/gfp.h>, so explicit
includes were added where necessary.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Replace usages of CPU_MASK_NONE, CPU_MASK_ALL, NODE_MASK_NONE,
NODE_MASK_ALL to reduce stack requirements for large NR_CPUS
and MAXNODES counts.
* In some cases, the cpumask variable was initialized but then overwritten
with another value. This is the case for changes like this:
- cpumask_t oldmask = CPU_MASK_ALL;
+ cpumask_t oldmask;
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The default_disable() function was changed in commit:
76d2160147
genirq: do not mask interrupts by default
It removed the mask function in favour of the default delayed
interrupt disabling. Unfortunately this also broke the shutdown in
free_irq() when the last handler is removed from the interrupt for
those architectures which rely on the default implementations. Now we
can end up with a enabled interrupt line after the last handler was
removed, which can result in spurious interrupts.
Fix this by adding a default_shutdown function, which is only
installed, when the irqchip implementation does provide neither a
shutdown nor a disable function.
[@stable: affected versions: .21 - .24 ]
Pointed-out-by: Michael Hennerich <Michael.Hennerich@analog.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: stable@kernel.org
Tested-by: Michael Hennerich <Michael.Hennerich@analog.com>
The functions time_before, time_before_eq, time_after, and
time_after_eq are more robust for comparing jiffies against other
values.
So following patch implements usage of the time_after() macro, defined
at linux/jiffies.h, which deals with wrapping correctly
Signed-off-by: S.Caglar Onur <caglar@pardus.org.tr>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Probing non-ISA interrupts using the handle_percpu_irq as their handle_irq
method may crash the system because handle_percpu_irq does not check
IRQ_WAITING. This for example hits the MIPS Qemu configuration.
This patch provides two helper functions set_irq_noprobe and set_irq_probe to
set rsp. clear the IRQ_NOPROBE flag. The only current caller is MIPS code
but this really belongs into generic code.
As an aside, interrupt probing these days has become a mostly obsolete if not
dangerous art. I think Linux interrupts should be changed to default to
non-probing but that's subject of this patch.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-and-tested-by: Rob Landley <rob@landley.net>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
these bugs are harder to find than they seem, a stackdump helps.
make it dependent on CONFIG_DEBUG_SHIRQ so that people can turn it off
if it annoys them.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This is useful to debug problems with interrupt handlers that return
sometimes IRQ_NONE.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This allows to change them at runtime using sysfs. No need to
reboot to set them.
I only added aliases (kernel.noirqdebug etc.) so the old options
still work.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In commit 76d2160147 lazy irq disabling
was implemented, and the simple irq handler had a masking set to it.
Remy Bohmer discovered that some devices in the ARM architecture
would trigger the mask, but never unmask it. His patch to do the
unmasking was questioned by Russell King about masking simple irqs
to begin with. Looking further, it was discovered that the problems
Remy was seeing was due to improper use of the simple handler by
devices, and he later submitted patches to fix those. But the issue
that was uncovered was that the simple handler should never mask.
This patch reverts the masking in the simple handler.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
In __do_IRQ(), the normal case is that IRQ_DISABLED is checked and if set
the handler (handle_IRQ_event()) is not called.
Earlier in __do_IRQ(), if IRQ_PER_CPU is set the code does not check
IRQ_DISABLED and calls the handler even though IRQ_DISABLED is set. This
behavior seems unintentional.
One user encountering this behavior is the CPE handler (in
arch/ia64/kernel/mca.c). When the CPE handler encounters too many CPEs
(such as a solid single bit error), it sets up a polling timer and disables
the CPE interrupt (to avoid excessive overhead logging the stream of single
bit errors). disable_irq_nosync() is called which sets IRQ_DISABLED. The
IRQ_PER_CPU flag was previously set (in ia64_mca_late_init()). The net
result is the CPE handler gets called even though it is marked disabled.
If the behavior of not checking IRQ_DISABLED when IRQ_PER_CPU is set is
intentional, it would be worthy of a comment describing the intended
behavior. disable_irq_nosync() does call chip->disable() to provide a
chipset specifiec interface for disabling the interrupt, which avoids this
issue when used.
Signed-off-by: Russ Anderson <rja@sgi.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As it is some callers of synchronize_irq rely on memory barriers
to provide synchronisation against the IRQ handlers. For example,
the tg3 driver does
tp->irq_sync = 1;
smp_mb();
synchronize_irq();
and then in the IRQ handler:
if (!tp->irq_sync)
netif_rx_schedule(dev, &tp->napi);
Unfortunately memory barriers only work well when they come in
pairs. Because we don't actually have memory barriers on the
IRQ path, the memory barrier before the synchronize_irq() doesn't
actually protect us.
In particular, synchronize_irq() may return followed by the
result of netif_rx_schedule being made visible.
This patch (mostly written by Linus) fixes this by using spin
locks instead of memory barries on the synchronize_irq() path.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Compiling handle_percpu_irq only on uniprocessor generates an artificial
special case so a typical use like:
set_irq_chip_and_handler(irq, &some_irq_type, handle_percpu_irq);
needs to be conditionally compiled only on SMP systems as well and an
alternative UP construct is usually needed - for no good reason.
This fixes uniprocessor configurations for some MIPS SMP systems.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andy Gospodarek pointed out that because we return in the middle of the
free_irq() function, we never actually do call the IRQ handler that just
got deregistered. This should fix it, although I expect Andrew will want
to convert those 'return's to 'break'. That's a separate change though.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: Fernando Luis Vzquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mariusz Kozlowski reported lockdep's warning:
> =================================
> [ INFO: inconsistent lock state ]
> 2.6.23-rc2-mm1 #7
> ---------------------------------
> inconsistent {in-hardirq-W} -> {hardirq-on-W} usage.
> ifconfig/5492 [HC0[0]:SC0[0]:HE1:SE1] takes:
> (&tp->lock){+...}, at: [<de8706e0>] rtl8139_interrupt+0x27/0x46b [8139too]
> {in-hardirq-W} state was registered at:
> [<c0138eeb>] __lock_acquire+0x949/0x11ac
> [<c01397e7>] lock_acquire+0x99/0xb2
> [<c0452ff3>] _spin_lock+0x35/0x42
> [<de8706e0>] rtl8139_interrupt+0x27/0x46b [8139too]
> [<c0147a5d>] handle_IRQ_event+0x28/0x59
> [<c01493ca>] handle_level_irq+0xad/0x10b
> [<c0105a13>] do_IRQ+0x93/0xd0
> [<c010441e>] common_interrupt+0x2e/0x34
...
> other info that might help us debug this:
> 1 lock held by ifconfig/5492:
> #0: (rtnl_mutex){--..}, at: [<c0451778>] mutex_lock+0x1c/0x1f
>
> stack backtrace:
...
> [<c0452ff3>] _spin_lock+0x35/0x42
> [<de8706e0>] rtl8139_interrupt+0x27/0x46b [8139too]
> [<c01480fd>] free_irq+0x11b/0x146
> [<de871d59>] rtl8139_close+0x8a/0x14a [8139too]
> [<c03bde63>] dev_close+0x57/0x74
...
This shows that a driver's irq handler was running both in hard interrupt
and process contexts with irqs enabled. The latter was done during
free_irq() call and was possible only with CONFIG_DEBUG_SHIRQ enabled.
This was fixed by another patch.
But similar problem is possible with request_irq(): any locks taken from
irq handler could be vulnerable - especially with soft interrupts. This
patch fixes it by disabling local interrupts during handler's run. (It
seems, disabling softirqs should be enough, but it needs more checking
on possible races or other special cases).
Reported-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl>
Signed-off-by: Jarek Poplawski <jarkao2@o2.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If we're going to run the handler from free_irq() then we must do it with
local irq's disabled. Otherwise lockdep complains that the handler is taking
irq-safe spinlocks in a non-irq-safe fashion.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
