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Subject: Re: [PATCH] powerpc: Reduce scariness of interrupt frames in stack
 traces
From: Michael Ellerman <mpe@ellerman.id.au>
To: Paul Mackerras <paulus@samba.org>
Date: Wed, 18 Jun 2014 18:20:15 +1000
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On Thu, 2014-06-12 at 16:53 +1000, Paul Mackerras wrote:
> Some people see things like "Exception: 501" in stack traces in dmesg
> and assume that means that something has gone badly wrong, when in
> fact "Exception: 501" just means a device interrupt was taken.
> This changes "Exception" to "interrupt" to make it clearer that we
> are just recording the fact of a change in control flow rather than
> some error condition.

Surely this would be preferable:

> diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
> index 31d0215..aa103dc 100644
> --- a/arch/powerpc/kernel/process.c
> +++ b/arch/powerpc/kernel/process.c
> @@ -1577,7 +1577,7 @@ void show_stack(struct task_struct *tsk, unsigned long *stack)
>  			struct pt_regs *regs = (struct pt_regs *)
>  				(sp + STACK_FRAME_OVERHEAD);
>  			lr = regs->link;
> -			printk("--- Exception: %lx at %pS\n    LR = %pS\n",
> +			printk("--- 👋🌷🌹🌻🌼🐷🐰🐱💜: %lx at %pS\n    LR = %pS\n",
>  			       regs->trap, (void *)regs->nip, (void *)lr);
>  			firstframe = 1;
>  		}