Re: [Xen-devel] [PATCH v9 10/12] x86/xen: Bypass intr mode setup in enlighten_pv system

From: Juergen Gross
Date: Wed Sep 13 2017 - 05:45:33 EST


On 13/09/17 11:12, Dou Liyang wrote:
> XEN PV overrides smp_prepare_cpus(). xen_pv_smp_prepare_cpus()
> initializes interrupts in the XEN PV specific way and does not invoke
> native_smp_prepare_cpus(). As a consequence, x86_init.intr_mode_init() is
> not invoked either.
>
> The invocation of x86_init.intr_mode_init() will be moved from
> native_smp_prepare_cpus() in a follow up patch to solve <INSERT
> REASON/PROBLEM>.

I asked you to be more specific here before. So: what will be solved?
Can I select a problem I like? ;-)

> That move would cause the invocation of x86_init.intr_mode_init() for XEN
> PV platforms. To prevent that, override the default x86_init.intr_mode_init()
> callback with a noop().
>
> [Rewrited by Thomas Gleixner <tglx@xxxxxxxxxxxxx>]

Rewritten?

> Signed-off-by: Dou Liyang <douly.fnst@xxxxxxxxxxxxxx>
> Cc: xen-devel@xxxxxxxxxxxxxxxxxxxx
> Cc: boris.ostrovsky@xxxxxxxxxx
> Cc: Juergen Gross <jgross@xxxxxxxx>

Regarding the changes below:

Acked-by: Juergen Gross <jgross@xxxxxxxx>


Juergen

> ---
> arch/x86/xen/enlighten_pv.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
> index ae2a2e2..934dc7f 100644
> --- a/arch/x86/xen/enlighten_pv.c
> +++ b/arch/x86/xen/enlighten_pv.c
> @@ -1232,6 +1232,7 @@ asmlinkage __visible void __init xen_start_kernel(void)
> x86_platform.get_nmi_reason = xen_get_nmi_reason;
>
> x86_init.resources.memory_setup = xen_memory_setup;
> + x86_init.irqs.intr_mode_init = x86_init_noop;
> x86_init.oem.arch_setup = xen_arch_setup;
> x86_init.oem.banner = xen_banner;
>
>