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SubjectQuestion about apds990x.ko

While searching for races in the Linux kernel I've come across
"drivers/misc/apds990x.ko" module. Here are questions that I came up
with while analyzing results. Lines are given using the info from Linux

Consider the following case:

Thread 1: Thread 2:
apds990x_resume apds990x_irq
-> apds990x_chip_on if (!pm_runtime_suspended
-> apds990x_configure if (status & APDS990X_ST_AINT) {
chip->again_meas = 1 chip->again_meas = chip->again_next
(apds990x.c: line 571) (apds990x.c: line 505)

First question. Is this race feasible from your point of view?
Second question. The check for the device suspension status
(pm_runtime_suspended()) is present in the interrupt handler, but the
functions pm_runtime_set_suspended / pm_runtime_set_active are not used
in apds990x_suspend / apds990x_resume respectively. Do you know about
any other method being used to make the modification of suspension status?

Thank you for your time.

-- Anton Volkov
Linux Verification Center, ISPRAS

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