Re: [PATCH] PCI/LINK: bw_notification: Do not leave interrupt handler NULL

[Alex G.]

On 3/20/19 8:46 AM, Bjorn Helgaas wrote:
> Hi Alexandru,
>
> On Mon, Mar 18, 2019 at 08:12:04PM -0500, Alexandru Gagniuc wrote:
> > A threaded IRQ with a NULL handler does not work with level-triggered
> > interrupts. request_threaded_irq() will return an error:
> >
> >    genirq: Threaded irq requested with handler=NULL and !ONESHOT for irq 16
> >    pcie_bw_notification: probe of 0000:00:1b.0:pcie010 failed with error -22
> >
> > For level interrupts we need to silence the interrupt before exiting
> > the IRQ handler, so just clear the PCI_EXP_LNKSTA_LBMS bit there.
> >
> > Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Alexandru Gagniuc <mr.nuke.me@xxxxxxxxx>
>
> What's your thought regarding Lukas' comment?  If you do repost this,
> please add a Fixes: tag to help connect this with the initial commit.

I like Lukas's idea. I should have this re-posted by end of week, unless 
there's an urgency to get it out earlier.

Alex