kernel_optimize_test/kernel/irq
Linus Torvalds dcc5c6f013 Three interrupt related fixes for X86:
- Move disabling of the local APIC after invoking fixup_irqs() to ensure
    that interrupts which are incoming are noted in the IRR and not ignored.
 
  - Unbreak affinity setting. The rework of the entry code reused the
    regular exception entry code for device interrupts. The vector number is
    pushed into the errorcode slot on the stack which is then lifted into an
    argument and set to -1 because that's regs->orig_ax which is used in
    quite some places to check whether the entry came from a syscall. But it
    was overlooked that orig_ax is used in the affinity cleanup code to
    validate whether the interrupt has arrived on the new target. It turned
    out that this vector check is pointless because interrupts are never
    moved from one vector to another on the same CPU. That check is a
    historical leftover from the time where x86 supported multi-CPU
    affinities, but not longer needed with the now strict single CPU
    affinity. Famous last words ...
 
  - Add a missing check for an empty cpumask into the matrix allocator. The
    affinity change added a warning to catch the case where an interrupt is
    moved on the same CPU to a different vector. This triggers because a
    condition with an empty cpumask returns an assignment from the allocator
    as the allocator uses for_each_cpu() without checking the cpumask for
    being empty. The historical inconsistent for_each_cpu() behaviour of
    ignoring the cpumask and unconditionally claiming that CPU0 is in the
    mask striked again. Sigh.
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Merge tag 'x86-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "Three interrupt related fixes for X86:

   - Move disabling of the local APIC after invoking fixup_irqs() to
     ensure that interrupts which are incoming are noted in the IRR and
     not ignored.

   - Unbreak affinity setting.

     The rework of the entry code reused the regular exception entry
     code for device interrupts. The vector number is pushed into the
     errorcode slot on the stack which is then lifted into an argument
     and set to -1 because that's regs->orig_ax which is used in quite
     some places to check whether the entry came from a syscall.

     But it was overlooked that orig_ax is used in the affinity cleanup
     code to validate whether the interrupt has arrived on the new
     target. It turned out that this vector check is pointless because
     interrupts are never moved from one vector to another on the same
     CPU. That check is a historical leftover from the time where x86
     supported multi-CPU affinities, but not longer needed with the now
     strict single CPU affinity. Famous last words ...

   - Add a missing check for an empty cpumask into the matrix allocator.

     The affinity change added a warning to catch the case where an
     interrupt is moved on the same CPU to a different vector. This
     triggers because a condition with an empty cpumask returns an
     assignment from the allocator as the allocator uses for_each_cpu()
     without checking the cpumask for being empty. The historical
     inconsistent for_each_cpu() behaviour of ignoring the cpumask and
     unconditionally claiming that CPU0 is in the mask struck again.
     Sigh.

  plus a new entry into the MAINTAINER file for the HPE/UV platform"

* tag 'x86-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/matrix: Deal with the sillyness of for_each_cpu() on UP
  x86/irq: Unbreak interrupt affinity setting
  x86/hotplug: Silence APIC only after all interrupts are migrated
  MAINTAINERS: Add entry for HPE Superdome Flex (UV) maintainers
2020-08-30 12:01:23 -07:00
..
affinity.c genirq/affinity: Remove const qualifier from node_to_cpumask argument 2019-08-28 12:20:43 +02:00
autoprobe.c genirq: Delay deactivation in free_irq() 2019-07-03 10:12:28 +02:00
chip.c irqchip updates for Linux 5.9 2020-08-03 14:33:23 +02:00
cpuhotplug.c genirq, sched/isolation: Isolate from handling managed interrupts 2020-01-22 16:29:49 +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/debugfs: Add missing irqchip flags 2020-07-27 16:20:40 +02:00
devres.c genirq/devres: Use struct_size() in devm_kzalloc() 2019-04-16 21:54:03 +02:00
dummychip.c genirq: Add missing SPDX identifiers 2018-03-20 14:23:28 +01:00
generic-chip.c genirq: Add missing SPDX identifiers 2018-03-20 14:23:28 +01:00
handle.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
internals.h genirq: Provide interrupt injection mechanism 2020-03-08 11:06:42 +01:00
ipi.c genirq: Fix various typos in comments 2018-12-18 14:22:28 +01:00
irq_sim.c genirq/irq_sim: Simplify the API 2020-05-18 10:30:21 +01:00
irqdesc.c genirq: Add protection against unsafe usage of generic_handle_irq() 2020-03-08 11:06:40 +01:00
irqdomain.c irqdomain: Export irq_domain_update_bus_token 2020-07-27 08:55:02 +01:00
Kconfig genirq: Remove preflow handler support 2020-07-04 10:02:06 +02:00
Makefile genirq/timings: Add selftest for circular array 2019-06-12 10:47:04 +02:00
manage.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
matrix.c genirq/matrix: Deal with the sillyness of for_each_cpu() on UP 2020-08-30 19:17:28 +02:00
migration.c genirq/migration: Avoid out of line call if pending is not set 2018-06-06 15:18:20 +02:00
msi.c x86/apic/msi: Plug non-maskable MSI affinity race 2020-02-01 09:31:47 +01:00
pm.c genirq/PM: Always unlock IRQ descriptor in rearm_wake_irq() 2020-08-12 11:04:05 +02:00
proc.c genirq/proc: Reject invalid affinity masks (again) 2020-02-14 09:43:17 +01:00
resend.c treewide: Replace DECLARE_TASKLET() with DECLARE_TASKLET_OLD() 2020-07-30 11:15:58 -07:00
settings.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
spurious.c genirq: Add missing __must_hold() sparse annotation 2020-01-09 18:03:37 +01:00
timings.c genirq/timings: Add selftest for next event computation 2019-06-12 10:47:05 +02:00