Re: [PATCH] tty add compat_ioctl

[Paul Fulghum <paulkf@microgate.com>]

Paul Fulghum wrote:
> Arnd Bergmann wrote:
>> - In your driver you don't get the big kernel lock in the 
>> compat_ioctl function. I assume that this is correct for
>> the particular driver, but it may be nice if you could
>> consequently also add an unlocked_ioctl function that can
>> be used without the BKL for native ioctls. It would be good
>> to hear an opinon on this from someone who has an insight
>> in tty locking issues though, so I'm Cc:ing some people
>> who have touched that recently.
> 
> I don't count on higher level locking for
> synchronization issues specific to the driver.
> 
> I thought the current compat_ioctl() was already
> meant to *not* have the BKL just like unlocked_ioctl.
> My thought was that any driver getting a recent update
> like compat_ioctl() would need to be reviewed for BKL
> safety and take the lock manually if necessary.

Nevermind. I misread what you wrote (I'm tired).
Yes, adding an unlocked_ioctl() makes sense.

--
Paul