Re: [RFC v3 2/2] arm64: kprobes: Allow reentering kprobes while single-stepping

On Fri, Jul 10, 2026 at 06:32:55AM +0000, Pu Hu wrote:

From: Pu Hu <redacted>

A kprobe can be hit while another kprobe is in KPROBE_HIT_SS state. This
can happen when tracing or perf code runs from the debug exception path
while the first kprobe is preparing or executing its out-of-line
single-step instruction.

I don't understand this part. The single-step runs with debug exceptions
disabled (kprobes_save_local_irqflag() sets PSTATE.D) so how do we end
up taking one?

Will