Re: [PATCH] bpf: Fix preempt_enable_no_resched() abuse
From: Linus Torvalds
Date: Tue Apr 23 2019 - 16:45:40 EST
On Tue, Apr 23, 2019 at 1:35 PM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
>
> That one 'funnily' doesn't actually work; cond_resched() is a no-op on
> PREEMPT=y.
Uhhuh. I "knew" that, but it's one of those bitrotting things.
Which does make your argument stronger, of course. This is way too
easy to get wrong even if you think you are being careful.
I guess it could be another thing to check for with objtool, since you
have now gotten the experience with it ;)
Linus