Re: [PATCH RESENT] dm: Check kthread_run's return value

From: Minfei Huang
Date: Wed Jul 06 2016 - 09:38:49 EST


On 07/06/16 at 09:31P, Mike Snitzer wrote:
> On Wed, Jul 06 2016 at 9:27am -0400,
> Minfei Huang <mnghuan@xxxxxxxxx> wrote:
>
> > On 07/06/16 at 09:16P, Mike Snitzer wrote:
> > > On Mon, Jul 04 2016 at 11:25am -0400,
> > > Minfei Huang <mnghuan@xxxxxxxxx> wrote:
> > >
> > > > kthread function is used to process kthread_work. And there is no return
> > > > value checking during create this thread. Add this checking to fix this
> > > > issue.
> > > >
> > > > Signed-off-by: Minfei Huang <mnghuan@xxxxxxxxx>
> > > This needed rebasing against linux-dm.git's 'for-next'. I've now staged
> > > this fix for 4.8 inclusion, see:
> > > https://git.kernel.org/cgit/linux/kernel/git/device-mapper/linux-dm.git/commit/?h=for-next&id=7193a9defcab6f3d3f1eb64c68bad7534e5a39ad
> >
> > Seems that we should fix it in stable as well.
>
> Given the code movement it isn't easy to do (by simply adding a stable@
> cc). I've not seen a single report of an ignored kthread_run() failure
> for multipath using .request_fn interface.

Yep, this bug will be trigged in very restrict condition, also dm is
installed in boot time when there are a lot of memory avaiable.

Thanks
Minfei