<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/kernel/irq, branch v5.4.300</title>
<subtitle>Linux Kernel
</subtitle>
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<updated>2025-10-02T11:34:29Z</updated>
<entry>
<title>genirq: Provide new interfaces for affinity hints</title>
<updated>2025-10-02T11:34:29Z</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2021-09-03T15:24:17Z</published>
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<id>urn:sha1:7b2a67322aff353c70ba215b7c7f15df6810f274</id>
<content type='text'>
[ Upstream commit 65c7cdedeb3026fabcc967a7aae2f755ad4d0783 ]

The discussion about removing the side effect of irq_set_affinity_hint() of
actually applying the cpumask (if not NULL) as affinity to the interrupt,
unearthed a few unpleasantries:

  1) The modular perf drivers rely on the current behaviour for the very
     wrong reasons.

  2) While none of the other drivers prevents user space from changing
     the affinity, a cursorily inspection shows that there are at least
     expectations in some drivers.

#1 needs to be cleaned up anyway, so that's not a problem

#2 might result in subtle regressions especially when irqbalanced (which
   nowadays ignores the affinity hint) is disabled.

Provide new interfaces:

  irq_update_affinity_hint()  - Only sets the affinity hint pointer
  irq_set_affinity_and_hint() - Set the pointer and apply the affinity to
                                the interrupt

Make irq_set_affinity_hint() a wrapper around irq_apply_affinity_hint() and
document it to be phased out.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Nitesh Narayan Lal &lt;nitesh@redhat.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Link: https://lore.kernel.org/r/20210501021832.743094-1-jesse.brandeburg@intel.com
Link: https://lore.kernel.org/r/20210903152430.244937-2-nitesh@redhat.com
Stable-dep-of: 915470e1b44e ("i40e: fix IRQ freeing in i40e_vsi_request_irq_msix error path")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>genirq: Export affinity setter for modules</title>
<updated>2025-10-02T11:34:29Z</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2021-05-18T09:17:26Z</published>
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<id>urn:sha1:4dbabe8e6659d72b5315ebb53ea5b05d73ba0475</id>
<content type='text'>
[ Upstream commit 4d80d6ca5d77fde9880da8466e5b64f250e5bf82 ]

Perf modules abuse irq_set_affinity_hint() to set the affinity of system
PMU interrupts just because irq_set_affinity() was not exported.

The fact that irq_set_affinity_hint() actually sets the affinity is a
non-documented side effect and the name is clearly saying it's a hint.

To clean this up, export the real affinity setter.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Link: https://lore.kernel.org/r/20210518093117.968251441@linutronix.de
Stable-dep-of: 915470e1b44e ("i40e: fix IRQ freeing in i40e_vsi_request_irq_msix error path")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>genirq/affinity: Add irq_update_affinity_desc()</title>
<updated>2025-10-02T11:34:29Z</updated>
<author>
<name>John Garry</name>
<email>john.garry@huawei.com</email>
</author>
<published>2020-12-02T10:36:53Z</published>
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<id>urn:sha1:6fe90f60d0ff028a696aa8c503e635efe517860f</id>
<content type='text'>
[ Upstream commit 1d3aec89286254487df7641c30f1b14ad1d127a5 ]

Add a function to allow the affinity of an interrupt be switched to
managed, such that interrupts allocated for platform devices may be
managed.

This new interface has certain limitations, and attempts to use it in the
following circumstances will fail:
- For when the kernel is configured for generic IRQ reservation mode (in
  config GENERIC_IRQ_RESERVATION_MODE). The reason being that it could
  conflict with managed vs. non-managed interrupt accounting.
- The interrupt is already started, which should not be the case during
  init
- The interrupt is already configured as managed, which means double init

Suggested-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: John Garry &lt;john.garry@huawei.com&gt;
Signed-off-by: Marc Zyngier &lt;maz@kernel.org&gt;
Link: https://lore.kernel.org/r/1606905417-183214-2-git-send-email-john.garry@huawei.com
Stable-dep-of: 915470e1b44e ("i40e: fix IRQ freeing in i40e_vsi_request_irq_msix error path")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>genirq/irqdesc: Honor caller provided affinity in alloc_desc()</title>
<updated>2024-08-19T03:33:52Z</updated>
<author>
<name>Shay Drory</name>
<email>shayd@nvidia.com</email>
</author>
<published>2024-08-06T07:20:44Z</published>
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<content type='text'>
commit edbbaae42a56f9a2b39c52ef2504dfb3fb0a7858 upstream.

Currently, whenever a caller is providing an affinity hint for an
interrupt, the allocation code uses it to calculate the node and copies the
cpumask into irq_desc::affinity.

If the affinity for the interrupt is not marked 'managed' then the startup
of the interrupt ignores irq_desc::affinity and uses the system default
affinity mask.

Prevent this by setting the IRQD_AFFINITY_SET flag for the interrupt in the
allocator, which causes irq_setup_affinity() to use irq_desc::affinity on
interrupt startup if the mask contains an online CPU.

[ tglx: Massaged changelog ]

Fixes: 45ddcecbfa94 ("genirq: Use affinity hint in irqdesc allocation")
Signed-off-by: Shay Drory &lt;shayd@nvidia.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/all/20240806072044.837827-1-shayd@nvidia.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>genirq: Allow irq_chip registration functions to take a const irq_chip</title>
<updated>2024-08-19T03:33:45Z</updated>
<author>
<name>Marc Zyngier</name>
<email>maz@kernel.org</email>
</author>
<published>2022-02-09T16:25:59Z</published>
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<id>urn:sha1:f19bf41e73317b29331787bba0f5afdeb686a760</id>
<content type='text'>
[ Upstream commit 393e1280f765661cf39785e967676a4e57324126 ]

In order to let a const irqchip be fed to the irqchip layer, adjust
the various prototypes. An extra cast in irq_set_chip()() is required
to avoid a warning.

Signed-off-by: Marc Zyngier &lt;maz@kernel.org&gt;
Acked-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Link: https://lore.kernel.org/r/20220209162607.1118325-3-maz@kernel.org
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>genirq: Allow the PM device to originate from irq domain</title>
<updated>2024-08-19T03:33:43Z</updated>
<author>
<name>Marc Zyngier</name>
<email>maz@kernel.org</email>
</author>
<published>2022-02-01T12:02:59Z</published>
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<id>urn:sha1:9951e76f3988cc7157174e805ac5e9c2815995b7</id>
<content type='text'>
[ Upstream commit 1f8863bfb5ca500ea1c7669b16b1931ba27fce20 ]

As a preparation to moving the reference to the device used for
runtime power management, add a new 'dev' field to the irqdomain
structure for that exact purpose.

The irq_chip_pm_{get,put}() helpers are made aware of the dual
location via a new private helper.

No functional change intended.

Signed-off-by: Marc Zyngier &lt;maz@kernel.org&gt;
Reviewed-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Tested-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Tested-by: Tony Lindgren &lt;tony@atomide.com&gt;
Acked-by: Bartosz Golaszewski &lt;brgl@bgdev.pl&gt;
Link: https://lore.kernel.org/r/20220201120310.878267-2-maz@kernel.org
Stable-dep-of: 33b1c47d1fc0 ("irqchip/imx-irqsteer: Handle runtime power management correctly")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>genirq/cpuhotplug, x86/vector: Prevent vector leak during CPU offline</title>
<updated>2024-06-16T11:28:48Z</updated>
<author>
<name>Dongli Zhang</name>
<email>dongli.zhang@oracle.com</email>
</author>
<published>2024-05-22T22:02:18Z</published>
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<id>urn:sha1:f5f4675960609d8c5ee95f027fbf6ce380f98372</id>
<content type='text'>
commit a6c11c0a5235fb144a65e0cb2ffd360ddc1f6c32 upstream.

The absence of IRQD_MOVE_PCNTXT prevents immediate effectiveness of
interrupt affinity reconfiguration via procfs. Instead, the change is
deferred until the next instance of the interrupt being triggered on the
original CPU.

When the interrupt next triggers on the original CPU, the new affinity is
enforced within __irq_move_irq(). A vector is allocated from the new CPU,
but the old vector on the original CPU remains and is not immediately
reclaimed. Instead, apicd-&gt;move_in_progress is flagged, and the reclaiming
process is delayed until the next trigger of the interrupt on the new CPU.

Upon the subsequent triggering of the interrupt on the new CPU,
irq_complete_move() adds a task to the old CPU's vector_cleanup list if it
remains online. Subsequently, the timer on the old CPU iterates over its
vector_cleanup list, reclaiming old vectors.

However, a rare scenario arises if the old CPU is outgoing before the
interrupt triggers again on the new CPU.

In that case irq_force_complete_move() is not invoked on the outgoing CPU
to reclaim the old apicd-&gt;prev_vector because the interrupt isn't currently
affine to the outgoing CPU, and irq_needs_fixup() returns false. Even
though __vector_schedule_cleanup() is later called on the new CPU, it
doesn't reclaim apicd-&gt;prev_vector; instead, it simply resets both
apicd-&gt;move_in_progress and apicd-&gt;prev_vector to 0.

As a result, the vector remains unreclaimed in vector_matrix, leading to a
CPU vector leak.

To address this issue, move the invocation of irq_force_complete_move()
before the irq_needs_fixup() call to reclaim apicd-&gt;prev_vector, if the
interrupt is currently or used to be affine to the outgoing CPU.

Additionally, reclaim the vector in __vector_schedule_cleanup() as well,
following a warning message, although theoretically it should never see
apicd-&gt;move_in_progress with apicd-&gt;prev_cpu pointing to an offline CPU.

Fixes: f0383c24b485 ("genirq/cpuhotplug: Add support for cleaning up move in progress")
Signed-off-by: Dongli Zhang &lt;dongli.zhang@oracle.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240522220218.162423-1-dongli.zhang@oracle.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>genirq/generic_chip: Make irq_remove_generic_chip() irqdomain aware</title>
<updated>2023-11-28T16:50:18Z</updated>
<author>
<name>Herve Codina</name>
<email>herve.codina@bootlin.com</email>
</author>
<published>2023-10-24T15:03:35Z</published>
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<id>urn:sha1:a438322e00780c1209be29808da08d3e56110328</id>
<content type='text'>
commit 5e7afb2eb7b2a7c81e9f608cbdf74a07606fd1b5 upstream.

irq_remove_generic_chip() calculates the Linux interrupt number for removing the
handler and interrupt chip based on gc::irq_base as a linear function of
the bit positions of set bits in the @msk argument.

When the generic chip is present in an irq domain, i.e. created with a call
to irq_alloc_domain_generic_chips(), gc::irq_base contains not the base
Linux interrupt number.  It contains the base hardware interrupt for this
chip. It is set to 0 for the first chip in the domain, 0 + N for the next
chip, where $N is the number of hardware interrupts per chip.

That means the Linux interrupt number cannot be calculated based on
gc::irq_base for irqdomain based chips without a domain map lookup, which
is currently missing.

Rework the code to take the irqdomain case into account and calculate the
Linux interrupt number by a irqdomain lookup of the domain specific
hardware interrupt number.

[ tglx: Massage changelog. Reshuffle the logic and add a proper comment. ]

Fixes: cfefd21e693d ("genirq: Add chip suspend and resume callbacks")
Signed-off-by: Herve Codina &lt;herve.codina@bootlin.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20231024150335.322282-1-herve.codina@bootlin.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>genirq/matrix: Exclude managed interrupts in irq_matrix_allocated()</title>
<updated>2023-11-20T09:30:08Z</updated>
<author>
<name>Chen Yu</name>
<email>yu.c.chen@intel.com</email>
</author>
<published>2023-10-20T07:25:22Z</published>
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<id>urn:sha1:09ce728c9e27adbb6a3d59a8efe264684a4493fa</id>
<content type='text'>
[ Upstream commit a0b0bad10587ae2948a7c36ca4ffc206007fbcf3 ]

When a CPU is about to be offlined, x86 validates that all active
interrupts which are targeted to this CPU can be migrated to the remaining
online CPUs. If not, the offline operation is aborted.

The validation uses irq_matrix_allocated() to retrieve the number of
vectors which are allocated on the outgoing CPU. The returned number of
allocated vectors includes also vectors which are associated to managed
interrupts.

That's overaccounting because managed interrupts are:

  - not migrated when the affinity mask of the interrupt targets only
    the outgoing CPU

  - migrated to another CPU, but in that case the vector is already
    pre-allocated on the potential target CPUs and must not be taken into
    account.

As a consequence the check whether the remaining online CPUs have enough
capacity for migrating the allocated vectors from the outgoing CPU might
fail incorrectly.

Let irq_matrix_allocated() return only the number of allocated non-managed
interrupts to make this validation check correct.

[ tglx: Amend changelog and fixup kernel-doc comment ]

Fixes: 2f75d9e1c905 ("genirq: Implement bitmap matrix allocator")
Reported-by: Wendy Wang &lt;wendy.wang@intel.com&gt;
Signed-off-by: Chen Yu &lt;yu.c.chen@intel.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lore.kernel.org/r/20231020072522.557846-1-yu.c.chen@intel.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>genirq: Add IRQF_NO_AUTOEN for request_irq/nmi()</title>
<updated>2023-05-17T09:35:46Z</updated>
<author>
<name>Barry Song</name>
<email>song.bao.hua@hisilicon.com</email>
</author>
<published>2021-03-02T22:49:15Z</published>
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<id>urn:sha1:f5ce428e3eaeb01b1e1039272e3d7abbd27ff7e9</id>
<content type='text'>
[ Upstream commit cbe16f35bee6880becca6f20d2ebf6b457148552 ]

Many drivers don't want interrupts enabled automatically via request_irq().
So they are handling this issue by either way of the below two:

(1)
  irq_set_status_flags(irq, IRQ_NOAUTOEN);
  request_irq(dev, irq...);

(2)
  request_irq(dev, irq...);
  disable_irq(irq);

The code in the second way is silly and unsafe. In the small time gap
between request_irq() and disable_irq(), interrupts can still come.

The code in the first way is safe though it's subobtimal.

Add a new IRQF_NO_AUTOEN flag which can be handed in by drivers to
request_irq() and request_nmi(). It prevents the automatic enabling of the
requested interrupt/nmi in the same safe way as #1 above. With that the
various usage sites of #1 and #2 above can be simplified and corrected.

Signed-off-by: Barry Song &lt;song.bao.hua@hisilicon.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: dmitry.torokhov@gmail.com
Link: https://lore.kernel.org/r/20210302224916.13980-2-song.bao.hua@hisilicon.com
Stable-dep-of: 39db65a0a17b ("ASoC: es8316: Handle optional IRQ assignment")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
</feed>
