Re: [PATCH 1/1] tty: serial: owl: Initialize lock before registering port

From: Greg Kroah-Hartman
Date: Sat Jul 11 2020 - 02:30:42 EST


On Fri, Jul 10, 2020 at 07:30:22PM +0300, Andy Shevchenko wrote:
> On Fri, Jul 10, 2020 at 06:58:06PM +0300, Cristian Ciocaltea wrote:
> > On Fri, Jul 10, 2020 at 03:35:42PM +0200, Greg Kroah-Hartman wrote:
> > > On Fri, Jul 10, 2020 at 03:05:49PM +0300, Cristian Ciocaltea wrote:
>
> ...
>
> > > But I think we now have a core fix for this, no need to do this in any
> > > individual driver, right? Can you test my tty-linus branch to see if
> > > your change is still needed or not?
> >
> > I was not aware of the alternative approach, at that time Andy
> > confirmed the expected behaviour is to have a proper initialization
> > of the spinlock in the driver:
> > https://lore.kernel.org/lkml/CAHp75Vcz0a87LSnb6Ubt5_bSF3wUcs21GbP119trXER5KBDxbQ@xxxxxxxxxxxxxx/
> > https://lore.kernel.org/lkml/CAHp75Vf8xJ2yX-11JsTDnRvZQOK+16aePcB1AUzq=5oO-mFCGQ@xxxxxxxxxxxxxx/
> >
> > I have just checked the tty-linus tree and the only related change
> > seems to be f743061a85f5
> > ("serial: core: Initialise spin lock before use in uart_configure_port()")
> >
> > I tested it on top of 5.8.0-rc4 and I confirm it fixes the splat,
>
> Thank you for the testing!
>
> > however I'm a bit confused now regarding the recommended approach since
> > there is at least one more commit in the tty-linux tree that still
> > handles a similar issue in the driver specific code:
> > f38278e9b810 ("serial: sh-sci: Initialize spinlock for uart console")
>
> They now should be reverted.

Please send patches for that :)

thanks,

greg k-h