Messages in this thread | | | Date | Mon, 7 Jun 2021 10:06:44 +0200 | From | Johan Hovold <> | Subject | Re: [PATCH 2/3] dmaengine: usb-dmac: Fix PM reference leak in usb_dmac_probe() |
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On Thu, Jun 03, 2021 at 04:39:08PM +0530, Vinod Koul wrote: > On 31-05-21, 11:19, Johan Hovold wrote: > > On Mon, May 31, 2021 at 02:27:34PM +0530, Vinod Koul wrote: > > > On 31-05-21, 14:11, yukuai (C) wrote: > > > > On 2021/05/31 12:00, Vinod Koul wrote: > > > > > On 17-05-21, 16:18, Yu Kuai wrote: > > > > > > pm_runtime_get_sync will increment pm usage counter even it failed. > > > > > > Forgetting to putting operation will result in reference leak here. > > > > > > Fix it by replacing it with pm_runtime_resume_and_get to keep usage > > > > > > counter balanced.
> > > Yes the rumtime_pm is disabled on failure here and the count would have > > > no consequence... > > > > You should still balance the PM usage counter as it isn't reset for > > example when reloading the driver. > > Should I driver trust that on load PM usage counter is balanced and not > to be reset..?
Not sure what you're asking here. But a driver should never leave the PM usage counter unbalanced.
> > Using pm_runtime_resume_and_get() is one way of handling this, but > > alternatively you could also move the error_pm label above the > > pm_runtime_put() in the error path. > > That would be a better way I think
Johan
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