Messages in this thread | | | Subject | Re: Question about apds990x.ko | From | Anton Volkov <> | Date | Thu, 10 Aug 2017 18:11:44 +0300 |
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The author of this driver as well as bh1770glc.ko is Samu Onkalo. His e-mail that was found as a contact in the module's source is invalid. I tried to add him previous time (Question about bh1770glc.ko). The message was not delivered then.
On 10.08.2017 18:07, Greg KH wrote: > On Thu, Aug 10, 2017 at 05:57:30PM +0300, Anton Volkov wrote: >> 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? > > No idea, sorry. Maybe the driver authors know? > > greg k-h >
-- -- Anton Volkov Linux Verification Center, ISPRAS web: http://linuxtesting.org e-mail: avolkov@ispras.ru
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