Merge tag 'irq-core-2024-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull interrupt subsystem updates from Thomas Gleixner:
 "Core code:

   - Interrupt storm detection for the lockup watchdog:

     Lockups which are caused by interrupt storms are not easy to debug
     because there is no information about the events which make the
     lockup detector trigger.

     To make this more user friendly, provide an extenstion to interrupt
     statistics which allows to take snapshots and an interface to
     retrieve the delta to the snapshot. Use this new mechanism in the
     watchdog code to do a two stage lockup analysis by taking the
     snapshot and printing the deltas for the topmost active interrupts
     on the second trigger.

     Note: This contains both the interrupt and the watchdog changes as
     the latter depend on the former obviously.

   - Avoid summation loops in the /proc/interrupts output and use the
     global counter when possible

   - Skip suspended interrupts on CPU hotplug operations to ensure that
     they are not delivered before the system resumes the device drivers
     when coming out of suspend.

   - On CPU hot-unplug interrupts which are affine to the outgoing CPU
     are migrated to a different CPU in the affinity mask. This can fail
     when the CPUs have no vectors left. Instead of giving up try to
     migrate it to any online CPU and thereby breaking the affinity
     setting in order to prevent a stale device interrupt which targets
     an offline CPU

   - The usual small cleanups

  Driver code:

   - Support for the RISCV AIA MSI controller

   - Make the interrupt allocation for the Loongson PCH controller more
     flexible to prevent vector exhaustion

   - The usual set of cleanups and fixes all over the place"

* tag 'irq-core-2024-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  irqchip/gic-v3-its: Remove BUG_ON in its_vpe_irq_domain_alloc
  cpuidle: Avoid explicit cpumask allocation on stack
  irqchip/sifive-plic: Avoid explicit cpumask allocation on stack
  irqchip/riscv-aplic-direct: Avoid explicit cpumask allocation on stack
  irqchip/loongson-eiointc: Avoid explicit cpumask allocation on stack
  irqchip/gic-v3-its: Avoid explicit cpumask allocation on stack
  irqchip/irq-bcm6345-l1: Avoid explicit cpumask allocation on stack
  cpumask: Introduce cpumask_first_and_and()
  irqchip/irq-brcmstb-l2: Avoid saving mask on shutdown
  genirq: Reuse irq_is_nmi()
  genirq/cpuhotplug: Retry with cpu_online_mask when migration fails
  genirq/cpuhotplug: Skip suspended interrupts when restoring affinity
  arm64: dts: st: Add interrupt parent to pinctrl on stm32mp251
  arm64: dts: st: Add exti1 and exti2 nodes on stm32mp251
  ARM: dts: stm32: List exti parent interrupts on stm32mp131
  ARM: dts: stm32: List exti parent interrupts on stm32mp151
  arm64: Kconfig.platforms: Enable STM32_EXTI for ARCH_STM32
  irqchip/stm32-exti: Mark events reserved with RIF configuration check
  irqchip/stm32-exti: Skip secure events
  irqchip/stm32-exti: Convert driver to standard PM
  ...

2 files changed, 26 insertions, 0 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 859a4ecf0725..8bba448c819b 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1030,6 +1030,20 @@ config SOFTLOCKUP_DETECTOR
 	  chance to run.  The current stack trace is displayed upon
 	  detection and the system will stay locked up.
 
+config SOFTLOCKUP_DETECTOR_INTR_STORM
+	bool "Detect Interrupt Storm in Soft Lockups"
+	depends on SOFTLOCKUP_DETECTOR && IRQ_TIME_ACCOUNTING
+	select GENERIC_IRQ_STAT_SNAPSHOT
+	default y if NR_CPUS <= 128
+	help
+	  Say Y here to enable the kernel to detect interrupt storm
+	  during "soft lockups".
+
+	  "soft lockups" can be caused by a variety of reasons. If one is
+	  caused by an interrupt storm, then the storming interrupts will not
+	  be on the callstack. To detect this case, it is necessary to report
+	  the CPU stats and the interrupt counts during the "soft lockups".
+
 config BOOTPARAM_SOFTLOCKUP_PANIC
 	bool "Panic (Reboot) On Soft Lockups"
 	depends on SOFTLOCKUP_DETECTOR
diff --git a/lib/find_bit.c b/lib/find_bit.c
index 32f99e9a670e..dacadd904250 100644
--- a/lib/find_bit.c
+++ b/lib/find_bit.c
@@ -116,6 +116,18 @@ unsigned long _find_first_and_bit(const unsigned long *addr1,
 EXPORT_SYMBOL(_find_first_and_bit);
 #endif
 
+/*
+ * Find the first set bit in three memory regions.
+ */
+unsigned long _find_first_and_and_bit(const unsigned long *addr1,
+				      const unsigned long *addr2,
+				      const unsigned long *addr3,
+				      unsigned long size)
+{
+	return FIND_FIRST_BIT(addr1[idx] & addr2[idx] & addr3[idx], /* nop */, size);
+}
+EXPORT_SYMBOL(_find_first_and_and_bit);
+
 #ifndef find_first_zero_bit
 /*
  * Find the first cleared bit in a memory region.