lkml.org 
[lkml]   [2017]   [Aug]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectQuestion about apds990x.ko
Date
Hello.

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
v4.12.

Consider the following case:

Thread 1: Thread 2:
apds990x_suspend
apds990x_resume apds990x_irq
-> apds990x_chip_on if (!pm_runtime_suspended
(chip->client->dev)){
-> 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
web: http://linuxtesting.org
e-mail: avolkov@ispras.ru

\
 
 \ /
  Last update: 2017-08-10 16:58    [W:0.032 / U:2.868 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site