On Fri, Aug 16, 2019 at 05:35:36PM +0900, Jiada Wang wrote: > From: Bhuvanesh Surachari <bhuvanesh_surachari@xxxxxxxxxx> > > The de-/serializer driver has defined only irq_mask "ds90ub927_irq_mask" and > irq_unmask "ds90ub927_irq_unmask" callback functions. And de-/serializer > driver doesn't implement the irq_disable and irq_enable callback functions. > Hence inorder to invoke irq_mask callback function when disable_irq_nosync is > called the IRQ_DISABLE_UNLAZY interrupt flag should be set. If not the > disable_irq_nosync will just increment the depth field in the irq > descriptor only once as shown below. > > disable_irq_nosync > __disable_irq_nosync > __disable_irq (desc->depth++) > irq_disable > if irq_disable present -----------> if IRQ_DISABLE_UNLAZYflag set > | no | > yes | yes | > | | > desc->irq_data.chip->irq_disable desc->irq_data.chip->irq_unmask > (ds90ub927_irq_mask) > disable_irq > __disable_irq_nosync > __disable_irq > (desc->depth++) > But the enable_irq will try to decrement the depth field twice which generates > the backtrace stating "Unbalanced enable for irq 293". This is because there is > no IRQ_DISABLE_UNLAZY flag check while calling irq_unmask callback function > of the "ds90ub927_irq_unmask" de-/serializer via enable_irq. > > enable_irq > __enable_irq (desc->depth--) > irq_enable > if irq_enable present -------------> desc->irq_data.chip->irq_unmask > | no (ds90ub927_irq_unmask) > yes | enable_irq > | __enable_irq (desc->depth--) > (desc->irq_data.chip->irq_enable) I'd prefer if we instead did not use the disable_irq_nosync() in the driver. Thanks. -- Dmitry
