Re: [PATCH AUTOSEL 4.18 023/131] media: usbtv: use irqsave() in USB's complete callback

From: Sasha Levin
Date: Thu Sep 06 2018 - 20:22:48 EST


On Mon, Sep 03, 2018 at 09:16:32AM +0200, Sebastian Andrzej Siewior wrote:
>On 2018-09-02 13:03:27 [+0000], Sasha Levin wrote:
>> From: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
>>
>> [ Upstream commit 320905baa1dbddd3991c287432176d536e1d5b79 ]
>>
>> The USB completion callback does not disable interrupts while acquiring
>> the lock. We want to remove the local_irq_disable() invocation from
>> __usb_hcd_giveback_urb() and therefore it is required for the callback
>> handler to disable the interrupts while acquiring the lock.
>> The callback may be invoked either in IRQ or BH context depending on the
>> USB host controller.
>> Use the _irqsave() variant of the locking primitives.
>>
>> Cc: Hans Verkuil <hans.verkuil@xxxxxxxxx>
>> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
>> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
>> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
>
>This change (among the others that do the same in different drivers)
>does not fix a bug; it is just needed for "other reasons". While this
>series uncovered a few bugs, this is not one of them.
>There is no need to backport this stable.

Out it goes, thanks!