x86: intel_epb: Don't rely on link order
authorJames Morse <james.morse@arm.com>
Tue, 21 Nov 2023 13:44:00 +0000 (13:44 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 6 Dec 2023 03:41:48 +0000 (12:41 +0900)
commitd87c49377d5bbf3f5e5729c67f3892e1d2e6f661
tree4e843b81962c29522323e952be78e1eb56635c14
parentc72bbf200162a3b4b9e1baedec9008d8d710b427
x86: intel_epb: Don't rely on link order

intel_epb_init() is called as a subsys_initcall() to register cpuhp
callbacks. The callbacks make use of get_cpu_device() which will return
NULL unless register_cpu() has been called. register_cpu() is called
from topology_init(), which is also a subsys_initcall().

This is fragile. Moving the register_cpu() to a different
subsys_initcall()  leads to a NULL dereference during boot.

Make intel_epb_init() a late_initcall(), user-space can't provide a
policy before this point anyway.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>
Acked-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/E1r5R2m-00Csyb-2S@rmk-PC.armlinux.org.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/kernel/cpu/intel_epb.c