Hi Dmitry On 2019/08/17 2:26, Dmitry Torokhov wrote:
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.
sorry for the mistake, during forward port, I have already eliminated disable_irq_nosync(), so this patch is no longer needed, will drop it in v2 patch-set Thanks， Jiada
Thanks.
