[PATCH 6.16 0/2] genirq: Fixes for CPU hotplug / disable-depth regressions

From: Brian Norris
Date: Thu Jun 12 2025 - 14:33:57 EST


Hi,

Commit 788019eb559f ("genirq: Retain disable depth for managed
interrupts across CPU hotplug") was merged for v6.16-rc1, but it turns
out there were a few oversights.

One such report:

Re: [PATCH v2 1/2] genirq: Retain depth for managed IRQs across CPU hotplug
https://lore.kernel.org/lkml/24ec4adc-7c80-49e9-93ee-19908a97ab84@xxxxxxxxx/

This series contains two fixes for bugs that I've found locally and with
others' help. Some of the testing involved:

1. Aleksandrs Vinarskis tested suspend/resume + NVMe on Qualcomm
Snapdragon X1E/X1P laptops:
https://lore.kernel.org/lkml/CAMcHhXrT-y3EotxrcCZ0Pj8Sic6wsPSmRiW7NSzdG=9iH8xqKg@xxxxxxxxxxxxxx/

2. Locally-updated versions of kunit tests I've been working on for
various kernel/irq/ code:
Subject: [PATCH v4] genirq: Add kunit tests for depth counts
https://lore.kernel.org/lkml/20250522210837.4135244-1-briannorris@xxxxxxxxxxxx/

3. NVMe + x86 QEMU workloads, + system suspend

4. Pixel phones + modem driver + various CPU hotplug / system
suspend/resume tests.
(This is probably least compelling, because this doesn't use the
latest mainline kernel, and it uses non-upstream drivers for some
relevant components. But I figured I'd mention it, because we've
noticed some similar problems to #1 here.)

Regards,
Brian


Brian Norris (2):
genirq: Rebalance managed interrupts across multi-CPU hotplug
genirq/cpuhotplug: Restore affinity even for suspended IRQ

kernel/irq/chip.c | 8 ++++++++
kernel/irq/cpuhotplug.c | 7 -------
2 files changed, 8 insertions(+), 7 deletions(-)

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2.50.0.rc1.591.g9c95f17f64-goog