linux/kernel/irq
Vincent Whitchurch e2c12739cc genirq: Prevent nested thread vs synchronize_hardirq() deadlock
There is a possibility of deadlock if synchronize_hardirq() is called
when the nested threaded interrupt is active.  The following scenario
was observed on a uniprocessor PREEMPT_NONE system:

 Thread 1                      Thread 2

 handle_nested_thread()
  Set INPROGRESS
  Call ->thread_fn()
   thread_fn goes to sleep

                              free_irq()
                               __synchronize_hardirq()
                                Busy-loop forever waiting for INPROGRESS
                                to be cleared

The INPROGRESS flag is only supposed to be used for hard interrupt
handlers.  Remove the incorrect usage in the nested threaded interrupt
case and instead re-use the threads_active / wait_for_threads mechanism
to wait for nested threaded interrupts to complete.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230613-genirq-nested-v3-1-ae58221143eb@axis.com
2023-07-31 17:24:22 +02:00
..
affinity.c genirq/affinity: Move group_cpus_evenly() into lib/ 2023-01-17 18:50:06 +01:00
autoprobe.c genirq: Delay deactivation in free_irq() 2019-07-03 10:12:28 +02:00
chip.c genirq: Prevent nested thread vs synchronize_hardirq() deadlock 2023-07-31 17:24:22 +02:00
cpuhotplug.c sched/isolation: Use single feature type while referring to housekeeping cpumask 2022-02-16 15:57:55 +01:00
debug.h Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk 2018-02-01 13:36:15 -08:00
debugfs.c genirq: Allow fasteoi handler to resend interrupts on concurrent handling 2023-06-16 12:22:35 +01:00
devres.c genirq/devres: Use struct_size() in devm_kzalloc() 2019-04-16 21:54:03 +02:00
dummychip.c irq: Fix typos in comments 2021-03-22 04:23:14 +01:00
generic-chip.c genirq/generic_chip: Export irq_unmap_generic_chip 2022-07-20 12:05:55 +01:00
handle.c irq: remove unused flags argument from __handle_irq_event_percpu() 2022-01-07 00:25:25 +01:00
internals.h genirq: Prevent nested thread vs synchronize_hardirq() deadlock 2023-07-31 17:24:22 +02:00
ipi-mux.c genirq/ipi-mux: Use irq_domain_alloc_irqs() 2023-02-06 17:21:15 +00:00
ipi.c genirq/ipi: Fix NULL pointer deref in irq_data_get_affinity_mask() 2023-02-20 13:53:41 +01:00
irq_sim.c genirq/irq_sim: Make the irq_work always run in hard irq context 2022-05-14 17:48:27 +02:00
irqdesc.c genirq: Use a maple tree for interrupt descriptor management 2023-05-24 11:39:44 +02:00
irqdomain.c irqdomain: Use return value of strreplace() 2023-06-30 11:13:44 +02:00
Kconfig genirq: Add mechanism to multiplex a single HW IPI 2023-02-05 10:57:55 +00:00
Makefile genirq: Add mechanism to multiplex a single HW IPI 2023-02-05 10:57:55 +00:00
manage.c genirq: Prevent nested thread vs synchronize_hardirq() deadlock 2023-07-31 17:24:22 +02:00
matrix.c genirq/matrix: Remove redundant assignment to variable 'end' 2022-04-25 15:02:57 +02:00
migration.c genirq: Fix typos and misspellings in comments 2021-03-16 15:08:29 +01:00
msi.c x86/pci/xen: populate MSI sysfs entries 2023-05-24 18:08:49 +02:00
pm.c genirq/PM: Unexport {suspend,resume}_device_irqs() 2022-06-13 12:27:37 +02:00
proc.c proc: remove PDE_DATA() completely 2022-01-22 08:33:37 +02:00
resend.c genirq: Use hlist for managing resend handlers 2023-05-24 11:39:44 +02:00
settings.h genirq: Add a IRQF_NO_DEBUG flag 2021-05-17 20:01:35 +02:00
spurious.c genirq: Disable irqfixup/poll on PREEMPT_RT. 2021-09-19 23:01:15 +02:00
timings.c Updates to the interrupt core and driver subsystems: 2021-08-30 14:38:37 -07:00