On Thu, Feb 4, 2021 at 6:26 AM Lai Jiangshan <jiangshan...@gmail.com> wrote: > > From: Lai Jiangshan <la...@linux.alibaba.com> > > When FSGSBASE is enabled, paranoid_entry() fetches the per-CPU > GSBASE value via __per_cpu_offset or pcpu_unit_offsets. > > When data breakpoint is set on __per_cpu_offset[cpu] (read-write > operation), the specific cpu will be stuck in the infinite #DB loop. > RCU will try to send NMI to the specific cpu, but it is not working > either since NMI also relies on paranoid_entry().
Should we consider having a .percpu..noinstr section and having objtool enforce this?
