[PATCH v4 0/2] ARM: Remaining PREEMPT_RT bits

Sebastian Andrzej Siewior
2026-01-16T17:00:52Z

this is the last batch I have to enable PREEMPT_RT on the ARM
architecture. It is just sending a signal with disabled interrupts and finally
enabling PREEMPT_RT on ARM.

Is this okay?

v3…v4: https://lore.kernel.org/all/20251110145555.2555055-1-bigeasy@linutronix.de
- Dropped applied patches
- Rebased the remaining one on top of the recent fault handler and branch
predictor fixes.

v2…v3: https://lore.kernel.org/all/20251103101545.760243-1-bigeasy@linutronix.de
- Collected tags.

v1…v2: https://lore.kernel.org/all/20251029155918.503060-1-bigeasy@linutronix.de
- Allow to enable jump-labels on UP. The UP build does not involve
stop_machine(). Reworked by Arnd.

- Instead of forbidding HAVE_GUP_FAST with HIGHPTE enabled just
disable HIGHPTE on PREEMPT_RT. As Arnd explained, HIGHPTE is rarely
needed.

- Don't let ARCH_SUPPORTS_RT depend on HAVE_POSIX_CPU_TIMERS_TASK_WORK
which in turn depends on !KVM. Since KVM has been removed from ARM
it is sufficient to unconditionally allow ARCH_SUPPORTS_RT. Noted
by Arnd.

Sebastian Andrzej Siewior (1):
ARM: Allow to enable RT

Yadi.hu (1):
ARM: mm: fault: Enable interrupts before invoking __do_user_fault()

arch/arm/Kconfig | 1 +
arch/arm/mm/fault.c | 4 ++++
2 files changed, 5 insertions(+)

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2.51.0