Web lists-archives.com

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




Hi Juergen,

At 09/13/2017 05:45 PM, Juergen Gross wrote:
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? ;-)

Oops, I am sorry I missed it. I will modify it.

...to solve the dump-capture kernel hangs, if there is a notsc option
in its command line.


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?

Yeah, yeah. poor english skill :-).


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>


Thank you for your acked, I will re-post it.

Thanks,
	dou.

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;