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Quoting the header comments, IRQF_ONESHOT is "Used by threaded interrupts
which need to keep the irq line disabled until the threaded handler has
been run.". When applied to an interrupt that doesn't request a threaded
irq then IRQF_ONESHOT has a lesser known (undocumented?) side effect,
which it to disable the forced threading of the irq. For "normal" kernels
(without forced threading) then, if there is no thread_fn, then
IRQF_ONESHOT is a nop.

In this case disabling forced threading is not appropriate for this driver
because it calls wake_up_all() and this API cannot be called from
no-thread interrupt handlers on PREEMPT_RT systems (deadlock risk, triggers
sleeping-while-atomic warnings).

Fix this by removing IRQF_ONESHOT.

Fixes: 22094814

 ("soc: qcom: Add AOSS QMP driver")
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
[bjorn: Added Fixes tag]
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/...