ARM: 7807/1: kexec: validate CPU hotplug support

Architectures should fully validate whether kexec is possible as part of
machine_kexec_prepare(), so that user-space's kexec_load() operation can
report any problems. Performing validation in machine_kexec() itself is
too late, since it is not allowed to return.

Prior to this patch, ARM's machine_kexec() was testing after-the-fact
whether machine_kexec_prepare() was able to disable all but one CPU.
Instead, modify machine_kexec_prepare() to validate all conditions
necessary for machine_kexec_prepare()'s to succeed. BUG if the validation
succeeded, yet disabling the CPUs didn't actually work.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Stephen Warren 2013-08-02 20:52:49 +01:00 committed by Russell King
parent 00efaa0250
commit 2103f6cba6
3 changed files with 29 additions and 4 deletions

View file

@ -145,6 +145,16 @@ int boot_secondary(unsigned int cpu, struct task_struct *idle)
return -ENOSYS;
}
int platform_can_cpu_hotplug(void)
{
#ifdef CONFIG_HOTPLUG_CPU
if (smp_ops.cpu_kill)
return 1;
#endif
return 0;
}
#ifdef CONFIG_HOTPLUG_CPU
static void percpu_timer_stop(void);