genirq/cpuhotplug: Restore affinity even for suspended IRQ
Commit 788019eb ("genirq: Retain disable depth for managed interrupts across CPU hotplug") tried to make managed shutdown/startup properly reference counted, but it missed the fact that the unplug and hotplug code has an intentional imbalance by skipping IRQS_SUSPENDED interrupts on the "restore" path. This means that if a managed-affinity interrupt was both suspended and managed-shutdown (such as may happen during system suspend / S3), resume skips calling irq_startup_managed(), and would again have an unbalanced depth this time, with a positive value (i.e., remaining unexpectedly masked). This IRQS_SUSPENDED check was introduced in commit a60dd06a ("genirq/cpuhotplug: Skip suspended interrupts when restoring affinity") for essentially the same reason as commit 788019eb, to prevent that irq_startup() would unconditionally re-enable an interrupt too early. Because irq_startup_managed() now respsects the disable-depth count, the IRQS_SUSPENDED check is not longer needed, and instead, it causes harm. Thus, drop the IRQS_SUSPENDED check, and restore balance. This effectively reverts commit a60dd06a ("genirq/cpuhotplug: Skip suspended interrupts when restoring affinity"), because it is replaced by commit 788019eb ("genirq: Retain disable depth for managed interrupts across CPU hotplug"). Fixes: 788019eb ("genirq: Retain disable depth for managed interrupts across CPU hotplug") Reported-by:Aleksandrs Vinarskis <alex.vinarskis@gmail.com> Signed-off-by:
Brian Norris <briannorris@chromium.org> Signed-off-by:
Thomas Gleixner <tglx@linutronix.de> Tested-by:
Aleksandrs Vinarskis <alex.vinarskis@gmail.com> Link: https://lore.kernel.org/all/20250612183303.3433234-3-briannorris@chromium.org Closes: https://lore.kernel.org/lkml/24ec4adc-7c80-49e9-93ee-19908a97ab84@gmail.com/
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