Re: [PATCH 2/2] xen/x86: Call cpu_startup_entry(CPUHP_AP_ONLINE_IDLE) from xen_play_dead()

From: Boris Ostrovsky
Date: Fri Mar 25 2016 - 11:08:36 EST


On 03/25/2016 10:53 AM, Konrad Rzeszutek Wilk wrote:
On Thu, Mar 17, 2016 at 09:03:25AM -0400, Boris Ostrovsky wrote:
This call has always been missing from xen_play dead() but until
recently this was rather benign. With new cpu hotplug framework
however this call is required, otherwise a hot-plugged CPU will not
Could you include the commit id of the 'new cpu hotplug' in case
anybody wants to backport this?

Sure.

It's commit 8df3e07e7f21 ("cpu/hotplug: Let upcoming cpu bring itself fully up").

Do you (or David) want me to re-send it?

-boris




Thanks!
be properly brough up (by never calling cpuhp_online_idle())

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
---
arch/x86/xen/smp.c | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 3c6d17f..719cf29 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -545,6 +545,8 @@ static void xen_play_dead(void) /* used only with HOTPLUG_CPU */
* data back is to call:
*/
tick_nohz_idle_enter();
+
+ cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
}
#else /* !CONFIG_HOTPLUG_CPU */
--
1.7.1