Re: kprobes broken since 0d00449c7a28 ("x86: Replace ist_enter() with nmi_enter()")

[Peter Zijlstra]

On Thu, Jan 28, 2021 at 06:45:56PM +0200, Nikolay Borisov wrote:
> it would be placed on the __fentry__ (and not endbr64) hence it works.
> So perhaps a workaround outside of bpf could essentially detect this
> scenario and adjust the probe to be on the __fentry__ and not preceding
> instruction if it's detected to be endbr64 ?

Arguably the fentry handler should also set the nmi context, it can,
after all, interrupt pretty much any other context by construction.