[SRU][Bionic][Cosmic][PATCH 1/1] powerpc/livepatch: Implement reliable stack tracing for the consistency model

[Michael Ellerman]

Joseph Salisbury <joseph.salisbury at canonical.com> writes:
> diff --git a/arch/powerpc/kernel/stacktrace.c b/arch/powerpc/kernel/stacktrace.c
> index d534ed901538..26a50603177c 100644
> --- a/arch/powerpc/kernel/stacktrace.c
> +++ b/arch/powerpc/kernel/stacktrace.c
> @@ -76,3 +81,115 @@ save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace)
>  	save_context_stack(trace, regs->gpr[1], current, 0);
>  }
>  EXPORT_SYMBOL_GPL(save_stack_trace_regs);
> +
> +#ifdef CONFIG_HAVE_RELIABLE_STACKTRACE
> +int
> +save_stack_trace_tsk_reliable(struct task_struct *tsk,
> +				struct stack_trace *trace)
> +{
...
> +		/*
> +		 * Mark stacktraces with kretprobed functions on them
> +		 * as unreliable.
> +		 */
> +		if (ip == (unsigned long)kretprobe_trampoline)
> +			return 1;

You may also want:

5e3f0d15ae5f ("powerpc/livepatch: Fix build error with kprobes disabled.")

cheers