Re: [PATCH RFC] fix sun6i crash on setup_pagetables

[Julien Grall <julien.grall@linaro.org>]

On 07/24/2013 01:14 PM, Bamvor Jian Zhang wrote:
> this patch move set_processor_id in front of setup_pagetables
> in order to fix crash when calling this_cpu in that functions.
> the HPTIDR is unknown value according to ARM ARM 7AR(DDI0406C),
> B4-1598. we should use it before using it.
> 
> but i do not know why other board like arndale board. should
> bootloader write this register?

On the Arndale, by default the value of HPTIDR is equal to 0. So it
works without any issue.

During the afternoon, I have noticed this error and send a similar
patch few minutes ago. I also moved percpu_init_areas earlier.

For the next patches, could you add the appropriate people? It will
avoid to loose your patch with the other mail of the mailing list :).

> 
> Signed-off-by: Bamvor Jian Zhang <bjzhang@suse.com>
> ---
>  xen/arch/arm/setup.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
> index 2f9fdc8..3bf1b40 100644
> --- a/xen/arch/arm/setup.c
> +++ b/xen/arch/arm/setup.c
> @@ -437,6 +437,7 @@ void __init start_xen(unsigned long boot_phys_offset,
>      cpus = smp_get_max_cpus();
>      cmdline_parse(device_tree_bootargs(device_tree_flattened));
>  
> +    set_processor_id(0); /* needed early, for this_cpu() */
>      setup_pagetables(boot_phys_offset, get_xen_paddr());
>      setup_mm(fdt_paddr, fdt_size);
>  
> @@ -459,7 +460,6 @@ void __init start_xen(unsigned long boot_phys_offset,
>      make_cpus_ready(cpus, boot_phys_offset);
>  
>      percpu_init_areas();

I think you can also move percpu_init_areas earlier.

> -    set_processor_id(0); /* needed early, for smp_processor_id() */
>      set_current((struct vcpu *)0xfffff000); /* debug sanity */
>      idle_vcpu[0] = current;
>  
>