Re: [PATCH 4.9 75/95] random: set up the NUMA crng instances after the CRNG is fully initialized

From: Greg KH
Date: Mon Apr 23 2018 - 14:02:08 EST


On Mon, Apr 23, 2018 at 11:56:37AM -0400, Theodore Y. Ts'o wrote:
> On Mon, Apr 23, 2018 at 07:21:10PM +0900, Tetsuo Handa wrote:
> > Greg Kroah-Hartman wrote:
> > > > I think this can be fixed by backporting commit 4a072c71f49b
> > > > "random: silence compiler warnings and fix race" but I'm not sure
> > > > whether that depends on other changes.
> > >
> > > According to Tetsuo Handa, it's also causing problems in mainline :(
> > >
> > > Ted, any thoughts as to what to do here?
> >
> > (Resending because Webmail post was rejected by both stable ML and linux-kernel ML.)
> >
> > Subject: random: GFP_KERNEL|__GFP_NOFAIL allocation from IRQ context
> >
> > Hello.
> >
> > Commit 8ef35c866f8862df ("random: set up the NUMA crng instances after
> > the CRNG is fully initialized") is causing sleep inside atomic warning
> > due to GFP_KERNEL|__GFP_NOFAIL allocation from IRQ context. Though it
> > unlikely sleeps because there will be enough free memory at boot up...
> >
> > Please don't backport that patch now.
>
> Yes, please hold off on this in the stable queues as well. What we'll
> probably need to do is call defer the processing to a workqueue in the
> CONFIG_NUMA case.

I've dropped this patch from 4.16.y, 4.14.y, and 4.9.y for now.

thanks,

greg k-h