- 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.
-----BEGIN PGP SIGNATURE-----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=zIi4
-----END PGP SIGNATURE-----
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