Re: [RFC PATCH] binder: Don't require the binder lock when killed in binder_thread_read()
From: Greg KH
Date: Mon Apr 03 2017 - 09:25:23 EST
On Sat, Apr 01, 2017 at 07:34:53PM -0700, Doug Anderson wrote:
> Hi,
>
> On Fri, Mar 31, 2017 at 11:48 PM, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > On Fri, Mar 31, 2017 at 02:00:13PM -0700, Doug Anderson wrote:
> >> On Fri, Mar 31, 2017 at 12:29 PM, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> >> BTW: I presume that nobody has decided that it would be a wise idea to
> >> pick the OOM reaper code back to any stable trees? It seemed a bit
> >> too scary to me, so I wrote a dumber (but easier to backport) solution
> >> that avoided the deadlocks I was seeing. http://crosreview.com/465189
> >> and the 3 patches above it in case anyone else stumbles on this thread
> >> and is curious.
> >
> > What specific upstream OOM patches are you referring to? I'm always
> > glad to review patches for stable kernels, just email
> > stable@xxxxxxxxxxxxxxx the git commit ids and we can take it from there.
>
> +stable
>
> I was wondering about the concept of porting the OOM Reaper back to
> older kernels. The OOM reaper was originally introduced in:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/mm/oom_kill.c?id=aac453635549699c13a84ea1456d5b0e574ef855
>
> Basically the problem described in that patch exists in many older
> kernels and I've certainly seen crashes related to this in 3.10, but I
> believe older kernels see the same problems too.
>
> Personally I wouldn't know exactly which patches were important to
> backport and how far to go. One could arbitrarily try to backport up
> to 4.6.7 (since 4.6 was the first kernel to really have the OOM
> reaper) and ignore all the reaper fixes that landed since then. This
> would probably be doable for kernel 4.4, though if anyone was trying
> to support older kernels it might get harder.
Well, I would need someone to give me a list of commits, and actually
test it to see if it is something that people use/want before I can
queue anything up for a stable release...
{hint}
thanks,
greg k-h