Commit c185ddec authored by Juergen Gross's avatar Juergen Gross

xen/x86: fix cpu hotplug

Commit dc6416f1 ("xen/x86: Call
cpu_startup_entry(CPUHP_AP_ONLINE_IDLE) from xen_play_dead()")
introduced an error leading to a stack overflow of the idle task when
a cpu was brought offline/online many times: by calling
cpu_startup_entry() instead of returning at the end of xen_play_dead()
do_idle() would be entered again and again.

Don't use cpu_startup_entry(), but cpuhp_online_idle() instead allowing
to return from xen_play_dead().

Cc: <stable@vger.kernel.org> # 4.12
Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
Reviewed-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
parent 29d11cfd
......@@ -19,6 +19,7 @@
#include <linux/irq_work.h>
#include <linux/tick.h>
#include <linux/nmi.h>
#include <linux/cpuhotplug.h>
#include <asm/paravirt.h>
#include <asm/desc.h>
......@@ -413,7 +414,7 @@ static void xen_pv_play_dead(void) /* used only with HOTPLUG_CPU */
*/
tick_nohz_idle_enter();
cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
cpuhp_online_idle(CPUHP_AP_ONLINE_IDLE);
}
#else /* !CONFIG_HOTPLUG_CPU */
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment