Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Wed, 20 Mar 2019 14:35:04 -0500
From:   Bjorn Helgaas <helgaas@kernel.org>
To:     "Alex G." <mr.nuke.me@gmail.com>
Cc:     austin_bolen@dell.com, alex_gagniuc@dellteam.com,
        keith.busch@intel.com, Shyam_Iyer@Dell.com, lukas@wunner.de,
        okaya@kernel.org, torvalds@linux-foundation.org,
        linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] PCI/LINK: bw_notification: Do not leave interrupt
 handler NULL
Message-ID: <20190320193504.GC251185@google.com>
References: <CAHk-=wgM-5WfPW9LNHGfc1RxjVbDvHZqNfxyLVRSPP0R4jetDg@mail.gmail.com>
 <20190319011214.7847-1-mr.nuke.me@gmail.com>
 <20190320134632.GA251185@google.com>
 <dc22ee5c-5c63-a28d-c709-986287bb4a7e@gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <dc22ee5c-5c63-a28d-c709-986287bb4a7e@gmail.com>
User-Agent: Mutt/1.10.1 (2018-07-13)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Wed, Mar 20, 2019 at 08:48:33AM -0500, Alex G. wrote:
> On 3/20/19 8:46 AM, Bjorn Helgaas wrote:
> > 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@linux-foundation.org>
> > > Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
> > 
> > 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.

It would have been ideal to get the fix in -rc2, but I guess the end
of the week is OK because it's probably already too late for me to
apply it, run it through 0-day, get it in -next, and ask Linus to pull
it for -rc2.

Bjorn