On Wed, Jul 1, 2020 at 2:17 AM Daniel Borkmann <daniel@xxxxxxxxxxxxx> wrote:
> ("bpf: Replace cant_sleep() with cant_migrate()"). So perhaps one way to catch
> bugs for sleepable progs is to add a __might_sleep() into __bpf_prog_enter_sleepable()
that's a good idea.
> in order to trigger the assertion generally for DEBUG_ATOMIC_SLEEP configured
> kernels when we're in non-sleepable sections? Still not perfect since the code
> needs to be exercised first but better than nothing at all.
>
> >> What about others like security_sock_rcv_skb() for example which could be
> >> bh_lock_sock()'ed (or, generally hooks running in softirq context)?
> >
> > ahh. it's in running in bh at that point? then it should be added to blacklist.
>
> Yep.
I'm assuming KP will take care of it soon.
If not I'll come back to this set some time in August.
In the meantime I've pushed patch 1 that removes redundant sync_rcu to bpf-next,
since it's independent and it benefits from being in the tree as much
as possible.
