Hi, On Sat, May 16, 2020 at 1:47 AM liwei (GF) <[email protected]> wrote: > > >> - kprobes_save_local_irqflag(kcb, regs); > >> + kernel_prepare_single_step(&kcb->saved_irqflag, regs); > > > > Is there some reason to have two functions? It seems like every time > > you call kernel_enable_single_step() you'd want to call > > kernel_prepare_single_step(). ...and every time you call > > kernel_disable_single_step() you'd want to call > > kernel_cleanup_single_step(). > > > > Maybe you can just add the flags parameter to > > kernel_enable_single_step() / kernel_disable_single_step() and put the > > code in there? > > > > As kernel_enable_single_step() / kernel_disable_single_step() are also called > in > breakpoint_handler() and watchpoint_handler(), i am not sure it's a right > thing > to put the daif flag prepare/cleanup into them, especially we don't have a > context > to save the flags.
I think you misunderstood what I was suggesting. Maybe better with examples? I was suggesting doing this: kcb->saved_irqflag = kernel_enable_single_step(regs); ... kernel_disable_single_step(kcb->saved_irqflag, regs); To me that seems better than what you have now: kcb->saved_irqflag = kernel_prepare_single_step(regs); kernel_enable_single_step(regs); ... kernel_cleanup_single_step(kcb->saved_irqflag, regs); kernel_disable_single_step(); ...or am I confused? -Doug
