When poweroff machine, kernel_power_off() call disable_nonboot_cpus().
And if we have HOTPLUG_CPU configured, disable_nonboot_cpus() is not an
empty function but attempt to actually disable the nonboot cpus. Since
system state is SYSTEM_POWER_OFF, play_dead() won't be called and thus
disable_nonboot_cpus() hangs. Therefore, we make this patch to avoid
poweroff failure.
V2:
Make the From: address the same as Signed-off-by address.
Signed-off-by: Huacai Chen <[email protected]>
Signed-off-by: Hongliang Tao <[email protected]>
Signed-off-by: Hua Yan <[email protected]>
Cc: Yong Zhang <[email protected]>
Cc: [email protected]
---
arch/mips/kernel/process.c | 4 +---
1 files changed, 1 insertions(+), 3 deletions(-)
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index e9a5fd7..69b17a9 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -72,9 +72,7 @@ void __noreturn cpu_idle(void)
}
}
#ifdef CONFIG_HOTPLUG_CPU
- if (!cpu_online(cpu) && !cpu_isset(cpu, cpu_callin_map) &&
- (system_state == SYSTEM_RUNNING ||
- system_state == SYSTEM_BOOTING))
+ if (!cpu_online(cpu) && !cpu_isset(cpu, cpu_callin_map))
play_dead();
#endif
rcu_idle_exit();
--
1.7.7.3
On Mon, Aug 13, 2012 at 08:52:24PM +0800, Huacai Chen wrote:
> When poweroff machine, kernel_power_off() call disable_nonboot_cpus().
> And if we have HOTPLUG_CPU configured, disable_nonboot_cpus() is not an
> empty function but attempt to actually disable the nonboot cpus. Since
> system state is SYSTEM_POWER_OFF, play_dead() won't be called and thus
> disable_nonboot_cpus() hangs. Therefore, we make this patch to avoid
> poweroff failure.
> diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
> index e9a5fd7..69b17a9 100644
> --- a/arch/mips/kernel/process.c
> +++ b/arch/mips/kernel/process.c
> @@ -72,9 +72,7 @@ void __noreturn cpu_idle(void)
> }
> }
> #ifdef CONFIG_HOTPLUG_CPU
> - if (!cpu_online(cpu) && !cpu_isset(cpu, cpu_callin_map) &&
> - (system_state == SYSTEM_RUNNING ||
> - system_state == SYSTEM_BOOTING))
> + if (!cpu_online(cpu) && !cpu_isset(cpu, cpu_callin_map))
Looks good - but I'm wondering if the "!cpu_isset(cpu, cpu_callin_map)"
can be removed as well?
Also, which -stable branches is this patch applicable?
Ralf
On Tue, Aug 14, 2012 at 7:48 PM, Ralf Baechle <[email protected]> wrote:
> On Mon, Aug 13, 2012 at 08:52:24PM +0800, Huacai Chen wrote:
>
>> When poweroff machine, kernel_power_off() call disable_nonboot_cpus().
>> And if we have HOTPLUG_CPU configured, disable_nonboot_cpus() is not an
>> empty function but attempt to actually disable the nonboot cpus. Since
>> system state is SYSTEM_POWER_OFF, play_dead() won't be called and thus
>> disable_nonboot_cpus() hangs. Therefore, we make this patch to avoid
>> poweroff failure.
>
>> diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
>> index e9a5fd7..69b17a9 100644
>> --- a/arch/mips/kernel/process.c
>> +++ b/arch/mips/kernel/process.c
>> @@ -72,9 +72,7 @@ void __noreturn cpu_idle(void)
>> }
>> }
>> #ifdef CONFIG_HOTPLUG_CPU
>> - if (!cpu_online(cpu) && !cpu_isset(cpu, cpu_callin_map) &&
>> - (system_state == SYSTEM_RUNNING ||
>> - system_state == SYSTEM_BOOTING))
>> + if (!cpu_online(cpu) && !cpu_isset(cpu, cpu_callin_map))
>
> Looks good - but I'm wondering if the "!cpu_isset(cpu, cpu_callin_map)"
> can be removed as well?
For X86, IA64, ARM, SPARC64 and most other arch, "!cpu_online(cpu)" is
the only condition of play_dead(). I keep "!cpu_isset(cpu,
cpu_callin_map)" because this does't refuse poweroff and I don't know
why the old condition of play_dead() is so complex.
>
> Also, which -stable branches is this patch applicable?
3.3, 3.4 and 3.5 branch can use it, 3.2 and earlier kernels should do
some small changes.
>
> Ralf
>
On Tue, Aug 14, 2012 at 7:48 PM, Ralf Baechle <[email protected]> wrote:
> On Mon, Aug 13, 2012 at 08:52:24PM +0800, Huacai Chen wrote:
>
>> When poweroff machine, kernel_power_off() call disable_nonboot_cpus().
>> And if we have HOTPLUG_CPU configured, disable_nonboot_cpus() is not an
>> empty function but attempt to actually disable the nonboot cpus. Since
>> system state is SYSTEM_POWER_OFF, play_dead() won't be called and thus
>> disable_nonboot_cpus() hangs. Therefore, we make this patch to avoid
>> poweroff failure.
>
>> diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
>> index e9a5fd7..69b17a9 100644
>> --- a/arch/mips/kernel/process.c
>> +++ b/arch/mips/kernel/process.c
>> @@ -72,9 +72,7 @@ void __noreturn cpu_idle(void)
>> }
>> }
>> #ifdef CONFIG_HOTPLUG_CPU
>> - if (!cpu_online(cpu) && !cpu_isset(cpu, cpu_callin_map) &&
>> - (system_state == SYSTEM_RUNNING ||
>> - system_state == SYSTEM_BOOTING))
>> + if (!cpu_online(cpu) && !cpu_isset(cpu, cpu_callin_map))
>
> Looks good - but I'm wondering if the "!cpu_isset(cpu, cpu_callin_map)"
> can be removed as well?
I removed "!cpu_isset(cpu, cpu_callin_map)" and it works well on
Loongson, but I don't know whether it will affect cavium-octeon...
>
> Also, which -stable branches is this patch applicable?
>
> Ralf
>
On Mon, Aug 13, 2012 at 5:52 AM, Huacai Chen <[email protected]> wrote:
> When poweroff machine, kernel_power_off() call disable_nonboot_cpus().
> And if we have HOTPLUG_CPU configured, disable_nonboot_cpus() is not an
> empty function but attempt to actually disable the nonboot cpus. Since
> system state is SYSTEM_POWER_OFF, play_dead() won't be called and thus
> disable_nonboot_cpus() hangs. Therefore, we make this patch to avoid
> poweroff failure.
I have seen the same problem; sometimes it causes a kernel oops too.
> #ifdef CONFIG_HOTPLUG_CPU
> - if (!cpu_online(cpu) && !cpu_isset(cpu, cpu_callin_map) &&
> - (system_state == SYSTEM_RUNNING ||
> - system_state == SYSTEM_BOOTING))
> + if (!cpu_online(cpu) && !cpu_isset(cpu, cpu_callin_map))
> play_dead();
This fix works for me.
Acked-by: Kevin Cernekee <[email protected]>
I do see SMP boot problems ("Attempted to kill the idle task!" panic)
on a 4-way box if the !cpu_isset() check is removed.