Re: [PATCH v2 5/9] powerpc: Use preempt_model_str().

[Christophe Leroy]

Le 03/02/2025 à 15:16, Sebastian Andrzej Siewior a écrit :
> Use preempt_model_str() instead of manually conducting the preemption
> model. Use pr_emerg() instead of printk() to pass a loglevel.

Why use pr_emerg() for that line and not all other ones ?

The purpose of using printk() is to get it at the level defined by 
CONFIG_MESSAGE_LOGLEVEL_DEFAULT and I think it is important to have the 
full Oops block at the same level.

> Cc: Madhavan Srinivasan <maddy@xxxxxxxxxxxxx>
> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
> Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
> Cc: Naveen N Rao <naveen@xxxxxxxxxx>
> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
> ---
>   arch/powerpc/kernel/traps.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
> index edf5cabe5dfdb..9eb383189cfb2 100644
> --- a/arch/powerpc/kernel/traps.c
> +++ b/arch/powerpc/kernel/traps.c
> @@ -263,10 +263,10 @@ static int __die(const char *str, struct pt_regs *regs, long err)
>   {
>   	printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
>   
> -	printk("%s PAGE_SIZE=%luK%s%s%s%s%s%s %s\n",
> +	pr_emerg("%s PAGE_SIZE=%luK%s %s %s%s%s%s %s\n",
>   	       IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN) ? "LE" : "BE",
>   	       PAGE_SIZE / 1024, get_mmu_str(),
> -	       IS_ENABLED(CONFIG_PREEMPT) ? " PREEMPT" : "",
> +	       preempt_model_str(),
>   	       IS_ENABLED(CONFIG_SMP) ? " SMP" : "",
>   	       IS_ENABLED(CONFIG_SMP) ? (" NR_CPUS=" __stringify(NR_CPUS)) : "",
>   	       debug_pagealloc_enabled() ? " DEBUG_PAGEALLOC" : "",