cxl/events: Return IRQ_NONE when no event is pending

CXL event interrupts may share an MSI/MSI-X vector with other event
logs or device features. Consequently, cxl_event_thread() is registered
with IRQF_SHARED and must determine whether the event-log facility
claimed the interrupt.

The handler masks the Device Event Status register to the event logs
supported by the driver. However, when no supported status bit is set,
it exits the processing loop and still returns IRQ_HANDLED. This
incorrectly reports that the interrupt was claimed and prevents the
generic spurious-interrupt detector from accounting it as unhandled.

Track whether the CXL event handler claimed the interrupt and return
IRQ_NONE when no supported event is detected. If no handler sharing the
vector claims a sustained interrupt storm, the generic spurious-
interrupt detector can eventually identify and disable the affected
IRQ.

Signed-off-by: Shaikh Kamaluddin <shaikhkamal2012@gmail.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>
Reviewed-by: Anisa Su <anisa.su@samsung.com>
Reviewed-by: Li Ming <ming.li@zohomail.com>
Link: https://patch.msgid.link/20260912093815.14455-1-shaikhkamal2012@gmail.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

0 files changed, 0 insertions, 0 deletions