Re: [RESEND PATCH] scsi: ufs: fix race between clock gating and devfreq scaling work

From: Subhash Jadavani
Date: Mon Oct 17 2016 - 20:15:41 EST


On 2016-10-14 13:47, Martin K. Petersen wrote:
"Subhash" == Subhash Jadavani <subhashj@xxxxxxxxxxxxxx> writes:

Subhash> UFS devfreq clock scaling work may require clocks to be ON if
Subhash> it need to execute some UFS commands hence it may request for
Subhash> clock hold before issuing the command. But if UFS clock gating
Subhash> work is already running in parallel, ungate work would end up
Subhash> waiting for the clock gating work to finish and as clock gating
Subhash> work would also wait for the clock scaling work to finish, we
Subhash> would enter in deadlock state. Here is the call trace during
Subhash> this deadlock state:

Somebody from the UFS camp, please review!

As there was no review so far, i have moved this patch as first patch in the new UFS bug fixes patch series ([PATCH v1 00/11] scsi: ufs: bug fixes patch series #1) sent by me today.

Thanks,
Subhash

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