Re: [PATCH] pci/switchtec: fix stream_open.cocci warnings (fwd)

[Julia Lawall]

On Wed, 19 Jun 2019, Bjorn Helgaas wrote:

> On Wed, Jun 19, 2019 at 04:27:52PM +0000, Kirill Smelkov wrote:
> > Hi Julia, everyone.
> >
> > On Wed, Jun 19, 2019 at 12:28:47PM +0200, Julia Lawall wrote:
> > > Hi,
> > >
> > > Can you forward this patch to the people below if you think it is
> > > appropriate?
> >
> > Yes, this patch is appropriate. It was actually part of
> > git.kernel.org/linus/c5bf68fe0c86 . It should be safe, (and desirable as
> > it removes a chance for deadlock) to apply it.
> >
> > Sebastian, Kurt, Logan, Bjorn, please consider picking it up.
>
> I don't get it.  This appeared in v5.2-rc1 as c5bf68fe0c86 ("*: convert
> stream-like files from nonseekable_open -> stream_open"), so it looks like
> this is already done.  What would you like me to do with it?

Somehow 0-day got a hold of it...  If there is nothing to do, just ignore
it.

thanks,
julia

>
> > > Could I tell the kbuild people to add you to the CC list for
> > > this semantic patch?
> >
> > Yes, sure. Please feel free to add me to CC list for stream_open.cocci
> > related patches.
> >
> > Kirill
> >
> >
> > > thanks,
> > > julia
> > >
> > > ---------- Forwarded message ----------
> > > Date: Wed, 19 Jun 2019 18:23:18 +0800
> > > From: kbuild test robot <lkp@xxxxxxxxx>
> > > To: kbuild@xxxxxx
> > > Cc: Julia Lawall <julia.lawall@xxxxxxx>
> > > Subject: [PATCH] pci/switchtec: fix stream_open.cocci warnings
> > >
> > > CC: kbuild-all@xxxxxx
> > > TO: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
> > > CC: Kurt Schwemmer <kurt.schwemmer@xxxxxxxxxxxxx>
> > > CC: Logan Gunthorpe <logang@xxxxxxxxxxxx>
> > > CC: Bjorn Helgaas <helgaas@xxxxxxxxxx>
> > > CC: linux-pci@xxxxxxxxxxxxxxx
> > > CC: linux-kernel@xxxxxxxxxxxxxxx
> > >
> > > From: kbuild test robot <lkp@xxxxxxxxx>
> > >
> > > drivers/pci/switch/switchtec.c:395:1-17: ERROR: switchtec_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
> > >
> > > Generated by: scripts/coccinelle/api/stream_open.cocci
> > >
> > > Fixes: a3a1e895d4fa ("pci/switchtec: Don't use completion's wait queue")
> > > Signed-off-by: kbuild test robot <lkp@xxxxxxxxx>
> > > ---
> > >
> > > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-5.0.y-rt-rebase
> > > head:   31cc76d5590f5e60c2f26f029e40bc7d0441d93f
> > > commit: a3a1e895d4fa0508e11ac9107ace883a5b2a4d3b [171/305] pci/switchtec: Don't use completion's wait queue
> > > :::::: branch date: 6 days ago
> > > :::::: commit date: 6 days ago
> > >
> > > Please take the patch only if it's a positive warning. Thanks!
> > >
> > >  switchtec.c |    2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > --- a/drivers/pci/switch/switchtec.c
> > > +++ b/drivers/pci/switch/switchtec.c
> > > @@ -392,7 +392,7 @@ static int switchtec_dev_open(struct ino
> > >  		return PTR_ERR(stuser);
> > >
> > >  	filp->private_data = stuser;
> > > -	nonseekable_open(inode, filp);
> > > +	stream_open(inode, filp);
> > >
> > >  	dev_dbg(&stdev->dev, "%s: %p\n", __func__, stuser);
> > >
>