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* [PATCH] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n
@ 2021-09-26  2:51 ` Xiaoming Ni
  0 siblings, 0 replies; 12+ messages in thread
From: Xiaoming Ni @ 2021-09-26  2:51 UTC (permalink / raw)
  To: linux-kernel, oss, mpe, benh, paulus, paul.gortmaker,
	Yuantian.Tang, chenhui.zhao, linuxppc-dev
  Cc: nixiaoming, wangle6, wangxiongfeng2

When CONFIG_SMP=y, timebase synchronization is required when the second
 kernel is started.
	arch/powerpc/kernel/smp.c:
	int __cpu_up(unsigned int cpu, struct task_struct *tidle)
	{
		...
		if (smp_ops->give_timebase)
			smp_ops->give_timebase();
		...
	}

	void start_secondary(void *unused)
	{
		...
		if (smp_ops->take_timebase)
			smp_ops->take_timebase();
		...
	}

When CONFIG_HOTPLUG_CPU=n and CONFIG_KEXEC_CORE=n,
 smp_85xx_ops.give_timebase is NULL,
 smp_85xx_ops.take_timebase is NULL,
As a result, the timebase is not synchronized.

Timebase  synchronization does not depend on CONFIG_HOTPLUG_CPU.

Fixes: 56f1ba280719 ("powerpc/mpc85xx: refactor the PM operations")
Cc: stable@vger.kernel.org #v4.6
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
---
 arch/powerpc/platforms/85xx/Makefile         | 2 +-
 arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c | 4 ++++
 arch/powerpc/platforms/85xx/smp.c            | 9 ++++-----
 3 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/platforms/85xx/Makefile b/arch/powerpc/platforms/85xx/Makefile
index 60e4e97a929d..71ce1f6b6966 100644
--- a/arch/powerpc/platforms/85xx/Makefile
+++ b/arch/powerpc/platforms/85xx/Makefile
@@ -3,7 +3,7 @@
 # Makefile for the PowerPC 85xx linux kernel.
 #
 obj-$(CONFIG_SMP) += smp.o
-obj-$(CONFIG_FSL_PMC)		  += mpc85xx_pm_ops.o
+obj-$(CONFIG_SMP) += mpc85xx_pm_ops.o
 
 obj-y += common.o
 
diff --git a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
index 7c0133f558d0..a5656b3e9701 100644
--- a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
+++ b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
@@ -17,6 +17,7 @@
 
 static struct ccsr_guts __iomem *guts;
 
+#ifdef CONFIG_FSL_PMC
 static void mpc85xx_irq_mask(int cpu)
 {
 
@@ -49,6 +50,7 @@ static void mpc85xx_cpu_up_prepare(int cpu)
 {
 
 }
+#endif
 
 static void mpc85xx_freeze_time_base(bool freeze)
 {
@@ -76,10 +78,12 @@ static const struct of_device_id mpc85xx_smp_guts_ids[] = {
 
 static const struct fsl_pm_ops mpc85xx_pm_ops = {
 	.freeze_time_base = mpc85xx_freeze_time_base,
+#ifdef CONFIG_FSL_PMC
 	.irq_mask = mpc85xx_irq_mask,
 	.irq_unmask = mpc85xx_irq_unmask,
 	.cpu_die = mpc85xx_cpu_die,
 	.cpu_up_prepare = mpc85xx_cpu_up_prepare,
+#endif
 };
 
 int __init mpc85xx_setup_pmc(void)
diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
index c6df294054fe..349298cd9671 100644
--- a/arch/powerpc/platforms/85xx/smp.c
+++ b/arch/powerpc/platforms/85xx/smp.c
@@ -40,7 +40,6 @@ struct epapr_spin_table {
 	u32	pir;
 };
 
-#ifdef CONFIG_HOTPLUG_CPU
 static u64 timebase;
 static int tb_req;
 static int tb_valid;
@@ -112,6 +111,7 @@ static void mpc85xx_take_timebase(void)
 	local_irq_restore(flags);
 }
 
+#ifdef CONFIG_HOTPLUG_CPU
 static void smp_85xx_cpu_offline_self(void)
 {
 	unsigned int cpu = smp_processor_id();
@@ -499,17 +499,16 @@ void __init mpc85xx_smp_init(void)
 #ifdef CONFIG_FSL_CORENET_RCPM
 	fsl_rcpm_init();
 #endif
-
-#ifdef CONFIG_FSL_PMC
-	mpc85xx_setup_pmc();
 #endif
+	mpc85xx_setup_pmc();
 	if (qoriq_pm_ops) {
 		smp_85xx_ops.give_timebase = mpc85xx_give_timebase;
 		smp_85xx_ops.take_timebase = mpc85xx_take_timebase;
+#ifdef CONFIG_HOTPLUG_CPU
 		smp_85xx_ops.cpu_offline_self = smp_85xx_cpu_offline_self;
 		smp_85xx_ops.cpu_die = qoriq_cpu_kill;
-	}
 #endif
+	}
 	smp_ops = &smp_85xx_ops;
 
 #ifdef CONFIG_KEXEC_CORE
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread
* [PATCH] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n
@ 2021-09-26  2:51 ` Xiaoming Ni
  0 siblings, 0 replies; 12+ messages in thread
From: Xiaoming Ni @ 2021-09-26  2:51 UTC (permalink / raw)
  To: linux-kernel, oss, mpe, benh, paulus, paul.gortmaker,
	Yuantian.Tang, chenhui.zhao, linuxppc-dev
  Cc: wangle6, nixiaoming, wangxiongfeng2

When CONFIG_SMP=y, timebase synchronization is required when the second
 kernel is started.
	arch/powerpc/kernel/smp.c:
	int __cpu_up(unsigned int cpu, struct task_struct *tidle)
	{
		...
		if (smp_ops->give_timebase)
			smp_ops->give_timebase();
		...
	}

	void start_secondary(void *unused)
	{
		...
		if (smp_ops->take_timebase)
			smp_ops->take_timebase();
		...
	}

When CONFIG_HOTPLUG_CPU=n and CONFIG_KEXEC_CORE=n,
 smp_85xx_ops.give_timebase is NULL,
 smp_85xx_ops.take_timebase is NULL,
As a result, the timebase is not synchronized.

Timebase  synchronization does not depend on CONFIG_HOTPLUG_CPU.

Fixes: 56f1ba280719 ("powerpc/mpc85xx: refactor the PM operations")
Cc: stable@vger.kernel.org #v4.6
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
---
 arch/powerpc/platforms/85xx/Makefile         | 2 +-
 arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c | 4 ++++
 arch/powerpc/platforms/85xx/smp.c            | 9 ++++-----
 3 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/platforms/85xx/Makefile b/arch/powerpc/platforms/85xx/Makefile
index 60e4e97a929d..71ce1f6b6966 100644
--- a/arch/powerpc/platforms/85xx/Makefile
+++ b/arch/powerpc/platforms/85xx/Makefile
@@ -3,7 +3,7 @@
 # Makefile for the PowerPC 85xx linux kernel.
 #
 obj-$(CONFIG_SMP) += smp.o
-obj-$(CONFIG_FSL_PMC)		  += mpc85xx_pm_ops.o
+obj-$(CONFIG_SMP) += mpc85xx_pm_ops.o
 
 obj-y += common.o
 
diff --git a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
index 7c0133f558d0..a5656b3e9701 100644
--- a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
+++ b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
@@ -17,6 +17,7 @@
 
 static struct ccsr_guts __iomem *guts;
 
+#ifdef CONFIG_FSL_PMC
 static void mpc85xx_irq_mask(int cpu)
 {
 
@@ -49,6 +50,7 @@ static void mpc85xx_cpu_up_prepare(int cpu)
 {
 
 }
+#endif
 
 static void mpc85xx_freeze_time_base(bool freeze)
 {
@@ -76,10 +78,12 @@ static const struct of_device_id mpc85xx_smp_guts_ids[] = {
 
 static const struct fsl_pm_ops mpc85xx_pm_ops = {
 	.freeze_time_base = mpc85xx_freeze_time_base,
+#ifdef CONFIG_FSL_PMC
 	.irq_mask = mpc85xx_irq_mask,
 	.irq_unmask = mpc85xx_irq_unmask,
 	.cpu_die = mpc85xx_cpu_die,
 	.cpu_up_prepare = mpc85xx_cpu_up_prepare,
+#endif
 };
 
 int __init mpc85xx_setup_pmc(void)
diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
index c6df294054fe..349298cd9671 100644
--- a/arch/powerpc/platforms/85xx/smp.c
+++ b/arch/powerpc/platforms/85xx/smp.c
@@ -40,7 +40,6 @@ struct epapr_spin_table {
 	u32	pir;
 };
 
-#ifdef CONFIG_HOTPLUG_CPU
 static u64 timebase;
 static int tb_req;
 static int tb_valid;
@@ -112,6 +111,7 @@ static void mpc85xx_take_timebase(void)
 	local_irq_restore(flags);
 }
 
+#ifdef CONFIG_HOTPLUG_CPU
 static void smp_85xx_cpu_offline_self(void)
 {
 	unsigned int cpu = smp_processor_id();
@@ -499,17 +499,16 @@ void __init mpc85xx_smp_init(void)
 #ifdef CONFIG_FSL_CORENET_RCPM
 	fsl_rcpm_init();
 #endif
-
-#ifdef CONFIG_FSL_PMC
-	mpc85xx_setup_pmc();
 #endif
+	mpc85xx_setup_pmc();
 	if (qoriq_pm_ops) {
 		smp_85xx_ops.give_timebase = mpc85xx_give_timebase;
 		smp_85xx_ops.take_timebase = mpc85xx_take_timebase;
+#ifdef CONFIG_HOTPLUG_CPU
 		smp_85xx_ops.cpu_offline_self = smp_85xx_cpu_offline_self;
 		smp_85xx_ops.cpu_die = qoriq_cpu_kill;
-	}
 #endif
+	}
 	smp_ops = &smp_85xx_ops;
 
 #ifdef CONFIG_KEXEC_CORE
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread
* Re: [PATCH] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n
  2021-09-26  2:51 ` Xiaoming Ni
@ 2021-09-26 12:34   ` Xiaoming Ni
  -1 siblings, 0 replies; 12+ messages in thread
From: Xiaoming Ni @ 2021-09-26 12:34 UTC (permalink / raw)
  To: linux-kernel, oss, mpe, benh, paulus, paul.gortmaker,
	Yuantian.Tang, chenhui.zhao, linuxppc-dev
  Cc: wangle6, wangxiongfeng2

On 2021/9/26 10:51, Xiaoming Ni wrote:
> When CONFIG_SMP=y, timebase synchronization is required when the second
>   kernel is started.
> 	arch/powerpc/kernel/smp.c:
> 	int __cpu_up(unsigned int cpu, struct task_struct *tidle)
> 	{
> 		...
> 		if (smp_ops->give_timebase)
> 			smp_ops->give_timebase();
> 		...
> 	}
> 
> 	void start_secondary(void *unused)
> 	{
> 		...
> 		if (smp_ops->take_timebase)
> 			smp_ops->take_timebase();
> 		...
> 	}
> 
> When CONFIG_HOTPLUG_CPU=n and CONFIG_KEXEC_CORE=n,
>   smp_85xx_ops.give_timebase is NULL,
>   smp_85xx_ops.take_timebase is NULL,
> As a result, the timebase is not synchronized.
> 
> Timebase  synchronization does not depend on CONFIG_HOTPLUG_CPU.
> 
> Fixes: 56f1ba280719 ("powerpc/mpc85xx: refactor the PM operations")
> Cc: stable@vger.kernel.org #v4.6
> Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
> ---
>   arch/powerpc/platforms/85xx/Makefile         | 2 +-
>   arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c | 4 ++++
>   arch/powerpc/platforms/85xx/smp.c            | 9 ++++-----
>   3 files changed, 9 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/85xx/Makefile b/arch/powerpc/platforms/85xx/Makefile
> index 60e4e97a929d..71ce1f6b6966 100644
> --- a/arch/powerpc/platforms/85xx/Makefile
> +++ b/arch/powerpc/platforms/85xx/Makefile
> @@ -3,7 +3,7 @@
>   # Makefile for the PowerPC 85xx linux kernel.
>   #
>   obj-$(CONFIG_SMP) += smp.o
> -obj-$(CONFIG_FSL_PMC)		  += mpc85xx_pm_ops.o
> +obj-$(CONFIG_SMP) += mpc85xx_pm_ops.o
>   
>   obj-y += common.o
>   
> diff --git a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
> index 7c0133f558d0..a5656b3e9701 100644
> --- a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
> +++ b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
> @@ -17,6 +17,7 @@
>   
>   static struct ccsr_guts __iomem *guts;
>   
> +#ifdef CONFIG_FSL_PMC
>   static void mpc85xx_irq_mask(int cpu)
>   {
>   
> @@ -49,6 +50,7 @@ static void mpc85xx_cpu_up_prepare(int cpu)
>   {
>   
>   }
> +#endif
>   
>   static void mpc85xx_freeze_time_base(bool freeze)
>   {
> @@ -76,10 +78,12 @@ static const struct of_device_id mpc85xx_smp_guts_ids[] = {
>   
>   static const struct fsl_pm_ops mpc85xx_pm_ops = {
>   	.freeze_time_base = mpc85xx_freeze_time_base,
> +#ifdef CONFIG_FSL_PMC
>   	.irq_mask = mpc85xx_irq_mask,
>   	.irq_unmask = mpc85xx_irq_unmask,
>   	.cpu_die = mpc85xx_cpu_die,
>   	.cpu_up_prepare = mpc85xx_cpu_up_prepare,
> +#endif
>   };
>   
>   int __init mpc85xx_setup_pmc(void)
> diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
> index c6df294054fe..349298cd9671 100644
> --- a/arch/powerpc/platforms/85xx/smp.c
> +++ b/arch/powerpc/platforms/85xx/smp.c
> @@ -40,7 +40,6 @@ struct epapr_spin_table {
>   	u32	pir;
>   };
>   
> -#ifdef CONFIG_HOTPLUG_CPU
>   static u64 timebase;
>   static int tb_req;
>   static int tb_valid;
> @@ -112,6 +111,7 @@ static void mpc85xx_take_timebase(void)
>   	local_irq_restore(flags);
>   }
>   
> +#ifdef CONFIG_HOTPLUG_CPU
>   static void smp_85xx_cpu_offline_self(void)
>   {
>   	unsigned int cpu = smp_processor_id();
> @@ -499,17 +499,16 @@ void __init mpc85xx_smp_init(void)
>   #ifdef CONFIG_FSL_CORENET_RCPM
>   	fsl_rcpm_init();
>   #endif
> -
> -#ifdef CONFIG_FSL_PMC
> -	mpc85xx_setup_pmc();
>   #endif
> +	mpc85xx_setup_pmc();
>   	if (qoriq_pm_ops) {
>   		smp_85xx_ops.give_timebase = mpc85xx_give_timebase;
>   		smp_85xx_ops.take_timebase = mpc85xx_take_timebase;
> +#ifdef CONFIG_HOTPLUG_CPU
>   		smp_85xx_ops.cpu_offline_self = smp_85xx_cpu_offline_self;
>   		smp_85xx_ops.cpu_die = qoriq_cpu_kill;
> -	}
>   #endif
> +	}
>   	smp_ops = &smp_85xx_ops;
>   
>   #ifdef CONFIG_KEXEC_CORE
> 


I found inconsistent time values on different CPUs on my mpc8572 and 
used this patch to fix it.
But today I found out in ppc64 testing that this patch causes the system 
to trigger oops in the function mpc85xx_freeze_time_base(): the variable 
"guts" is a null pointer.

I'm sorry to bother you.
I'll fix it and resend v2 later,

Thanks
Xiaoming Ni

^ permalink raw reply	[flat|nested] 12+ messages in thread
* Re: [PATCH] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n
@ 2021-09-26 12:34   ` Xiaoming Ni
  0 siblings, 0 replies; 12+ messages in thread
From: Xiaoming Ni @ 2021-09-26 12:34 UTC (permalink / raw)
  To: linux-kernel, oss, mpe, benh, paulus, paul.gortmaker,
	Yuantian.Tang, chenhui.zhao, linuxppc-dev
  Cc: wangle6, wangxiongfeng2

On 2021/9/26 10:51, Xiaoming Ni wrote:
> When CONFIG_SMP=y, timebase synchronization is required when the second
>   kernel is started.
> 	arch/powerpc/kernel/smp.c:
> 	int __cpu_up(unsigned int cpu, struct task_struct *tidle)
> 	{
> 		...
> 		if (smp_ops->give_timebase)
> 			smp_ops->give_timebase();
> 		...
> 	}
> 
> 	void start_secondary(void *unused)
> 	{
> 		...
> 		if (smp_ops->take_timebase)
> 			smp_ops->take_timebase();
> 		...
> 	}
> 
> When CONFIG_HOTPLUG_CPU=n and CONFIG_KEXEC_CORE=n,
>   smp_85xx_ops.give_timebase is NULL,
>   smp_85xx_ops.take_timebase is NULL,
> As a result, the timebase is not synchronized.
> 
> Timebase  synchronization does not depend on CONFIG_HOTPLUG_CPU.
> 
> Fixes: 56f1ba280719 ("powerpc/mpc85xx: refactor the PM operations")
> Cc: stable@vger.kernel.org #v4.6
> Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
> ---
>   arch/powerpc/platforms/85xx/Makefile         | 2 +-
>   arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c | 4 ++++
>   arch/powerpc/platforms/85xx/smp.c            | 9 ++++-----
>   3 files changed, 9 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/85xx/Makefile b/arch/powerpc/platforms/85xx/Makefile
> index 60e4e97a929d..71ce1f6b6966 100644
> --- a/arch/powerpc/platforms/85xx/Makefile
> +++ b/arch/powerpc/platforms/85xx/Makefile
> @@ -3,7 +3,7 @@
>   # Makefile for the PowerPC 85xx linux kernel.
>   #
>   obj-$(CONFIG_SMP) += smp.o
> -obj-$(CONFIG_FSL_PMC)		  += mpc85xx_pm_ops.o
> +obj-$(CONFIG_SMP) += mpc85xx_pm_ops.o
>   
>   obj-y += common.o
>   
> diff --git a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
> index 7c0133f558d0..a5656b3e9701 100644
> --- a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
> +++ b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
> @@ -17,6 +17,7 @@
>   
>   static struct ccsr_guts __iomem *guts;
>   
> +#ifdef CONFIG_FSL_PMC
>   static void mpc85xx_irq_mask(int cpu)
>   {
>   
> @@ -49,6 +50,7 @@ static void mpc85xx_cpu_up_prepare(int cpu)
>   {
>   
>   }
> +#endif
>   
>   static void mpc85xx_freeze_time_base(bool freeze)
>   {
> @@ -76,10 +78,12 @@ static const struct of_device_id mpc85xx_smp_guts_ids[] = {
>   
>   static const struct fsl_pm_ops mpc85xx_pm_ops = {
>   	.freeze_time_base = mpc85xx_freeze_time_base,
> +#ifdef CONFIG_FSL_PMC
>   	.irq_mask = mpc85xx_irq_mask,
>   	.irq_unmask = mpc85xx_irq_unmask,
>   	.cpu_die = mpc85xx_cpu_die,
>   	.cpu_up_prepare = mpc85xx_cpu_up_prepare,
> +#endif
>   };
>   
>   int __init mpc85xx_setup_pmc(void)
> diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
> index c6df294054fe..349298cd9671 100644
> --- a/arch/powerpc/platforms/85xx/smp.c
> +++ b/arch/powerpc/platforms/85xx/smp.c
> @@ -40,7 +40,6 @@ struct epapr_spin_table {
>   	u32	pir;
>   };
>   
> -#ifdef CONFIG_HOTPLUG_CPU
>   static u64 timebase;
>   static int tb_req;
>   static int tb_valid;
> @@ -112,6 +111,7 @@ static void mpc85xx_take_timebase(void)
>   	local_irq_restore(flags);
>   }
>   
> +#ifdef CONFIG_HOTPLUG_CPU
>   static void smp_85xx_cpu_offline_self(void)
>   {
>   	unsigned int cpu = smp_processor_id();
> @@ -499,17 +499,16 @@ void __init mpc85xx_smp_init(void)
>   #ifdef CONFIG_FSL_CORENET_RCPM
>   	fsl_rcpm_init();
>   #endif
> -
> -#ifdef CONFIG_FSL_PMC
> -	mpc85xx_setup_pmc();
>   #endif
> +	mpc85xx_setup_pmc();
>   	if (qoriq_pm_ops) {
>   		smp_85xx_ops.give_timebase = mpc85xx_give_timebase;
>   		smp_85xx_ops.take_timebase = mpc85xx_take_timebase;
> +#ifdef CONFIG_HOTPLUG_CPU
>   		smp_85xx_ops.cpu_offline_self = smp_85xx_cpu_offline_self;
>   		smp_85xx_ops.cpu_die = qoriq_cpu_kill;
> -	}
>   #endif
> +	}
>   	smp_ops = &smp_85xx_ops;
>   
>   #ifdef CONFIG_KEXEC_CORE
> 


I found inconsistent time values on different CPUs on my mpc8572 and 
used this patch to fix it.
But today I found out in ppc64 testing that this patch causes the system 
to trigger oops in the function mpc85xx_freeze_time_base(): the variable 
"guts" is a null pointer.

I'm sorry to bother you.
I'll fix it and resend v2 later,

Thanks
Xiaoming Ni

^ permalink raw reply	[flat|nested] 12+ messages in thread
* [PATCH v2 0/2] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n
  2021-09-26 12:34   ` Xiaoming Ni
@ 2021-09-29  3:36     ` Xiaoming Ni
  -1 siblings, 0 replies; 12+ messages in thread
From: Xiaoming Ni @ 2021-09-29  3:36 UTC (permalink / raw)
  To: oss, mpe, benh, paulus, paul.gortmaker, chenhui.zhao,
	Yuantian.Tang, linuxppc-dev, linux-kernel, stable, gregkh
  Cc: wangle6, liuwenliang, chenjianguo3, nixiaoming

When CONFIG_SMP=y, timebase synchronization is required for mpc8572 when
 the second kernel is started
	arch/powerpc/kernel/smp.c:
	int __cpu_up(unsigned int cpu, struct task_struct *tidle)
	{
		...
		if (smp_ops->give_timebase)
			smp_ops->give_timebase();
		...
	}

	void start_secondary(void *unused)
	{
		...
		if (smp_ops->take_timebase)
			smp_ops->take_timebase();
		...
	}

When CONFIG_HOTPLUG_CPU=n and CONFIG_KEXEC_CORE=n,
 smp_85xx_ops.give_timebase is NULL,
 smp_85xx_ops.take_timebase is NULL,
As a result, the timebase is not synchronized.

test code:
	for i in $(seq 1 3); do taskset 1 date; taskset 2 date; sleep 1; echo;done
log:
	Sat Sep 25 18:50:00 CST 2021
	Sat Sep 25 19:07:47 CST 2021

	Sat Sep 25 18:50:01 CST 2021
	Sat Sep 25 19:07:48 CST 2021

	Sat Sep 25 18:50:02 CST 2021
	Sat Sep 25 19:07:49 CST 2021

Code snippet about give_timebase and take_timebase assignments:
	arch/powerpc/platforms/85xx/smp.c:
	#ifdef CONFIG_HOTPLUG_CPU
	#ifdef CONFIG_FSL_CORENET_RCPM
		fsl_rcpm_init();
	#endif
	#ifdef CONFIG_FSL_PMC
		mpc85xx_setup_pmc();
	#endif
		if (qoriq_pm_ops) {
			smp_85xx_ops.give_timebase = mpc85xx_give_timebase;
			smp_85xx_ops.take_timebase = mpc85xx_take_timebase;

config dependency:
	FSL_CORENET_RCPM depends on the PPC_E500MC.
	FSL_PMC depends on SUSPEND.
	SUSPEND depends on ARCH_SUSPEND_POSSIBLE.
	ARCH_SUSPEND_POSSIBLE depends on !PPC_E500MC.

CONFIG_HOTPLUG_CPU and CONFIG_FSL_PMC require the timebase function, but
the timebase should not depend on CONFIG_HOTPLUG_CPU and CONFIG_FSL_PMC.
Therefore, adjust the macro control range. Ensure that the corresponding
 timebase hook function is not empty when the dtsi node is configured.

-----
changes in v2:
 1. add new patch: "powerpc:85xx:Fix oops when mpc85xx_smp_guts_ids node
  cannot be found"
 2. Using !CONFIG_FSL_CORENET_RCPM to manage the timebase code of !PPC_E500MC

v1:
 https://lore.kernel.org/lkml/20210926025144.55674-1-nixiaoming@huawei.com
------

Xiaoming Ni (2):
  powerpc:85xx:Fix oops when mpc85xx_smp_guts_ids node cannot be found
  powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n

 arch/powerpc/platforms/85xx/Makefile         |  4 +++-
 arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c |  7 +++++--
 arch/powerpc/platforms/85xx/smp.c            | 12 ++++++------
 3 files changed, 14 insertions(+), 9 deletions(-)

-- 
2.27.0


^ permalink raw reply	[flat|nested] 12+ messages in thread
* [PATCH v2 0/2] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n
@ 2021-09-29  3:36     ` Xiaoming Ni
  0 siblings, 0 replies; 12+ messages in thread
From: Xiaoming Ni @ 2021-09-29  3:36 UTC (permalink / raw)
  To: oss, mpe, benh, paulus, paul.gortmaker, chenhui.zhao,
	Yuantian.Tang, linuxppc-dev, linux-kernel, stable, gregkh
  Cc: liuwenliang, wangle6, nixiaoming, chenjianguo3

When CONFIG_SMP=y, timebase synchronization is required for mpc8572 when
 the second kernel is started
	arch/powerpc/kernel/smp.c:
	int __cpu_up(unsigned int cpu, struct task_struct *tidle)
	{
		...
		if (smp_ops->give_timebase)
			smp_ops->give_timebase();
		...
	}

	void start_secondary(void *unused)
	{
		...
		if (smp_ops->take_timebase)
			smp_ops->take_timebase();
		...
	}

When CONFIG_HOTPLUG_CPU=n and CONFIG_KEXEC_CORE=n,
 smp_85xx_ops.give_timebase is NULL,
 smp_85xx_ops.take_timebase is NULL,
As a result, the timebase is not synchronized.

test code:
	for i in $(seq 1 3); do taskset 1 date; taskset 2 date; sleep 1; echo;done
log:
	Sat Sep 25 18:50:00 CST 2021
	Sat Sep 25 19:07:47 CST 2021

	Sat Sep 25 18:50:01 CST 2021
	Sat Sep 25 19:07:48 CST 2021

	Sat Sep 25 18:50:02 CST 2021
	Sat Sep 25 19:07:49 CST 2021

Code snippet about give_timebase and take_timebase assignments:
	arch/powerpc/platforms/85xx/smp.c:
	#ifdef CONFIG_HOTPLUG_CPU
	#ifdef CONFIG_FSL_CORENET_RCPM
		fsl_rcpm_init();
	#endif
	#ifdef CONFIG_FSL_PMC
		mpc85xx_setup_pmc();
	#endif
		if (qoriq_pm_ops) {
			smp_85xx_ops.give_timebase = mpc85xx_give_timebase;
			smp_85xx_ops.take_timebase = mpc85xx_take_timebase;

config dependency:
	FSL_CORENET_RCPM depends on the PPC_E500MC.
	FSL_PMC depends on SUSPEND.
	SUSPEND depends on ARCH_SUSPEND_POSSIBLE.
	ARCH_SUSPEND_POSSIBLE depends on !PPC_E500MC.

CONFIG_HOTPLUG_CPU and CONFIG_FSL_PMC require the timebase function, but
the timebase should not depend on CONFIG_HOTPLUG_CPU and CONFIG_FSL_PMC.
Therefore, adjust the macro control range. Ensure that the corresponding
 timebase hook function is not empty when the dtsi node is configured.

-----
changes in v2:
 1. add new patch: "powerpc:85xx:Fix oops when mpc85xx_smp_guts_ids node
  cannot be found"
 2. Using !CONFIG_FSL_CORENET_RCPM to manage the timebase code of !PPC_E500MC

v1:
 https://lore.kernel.org/lkml/20210926025144.55674-1-nixiaoming@huawei.com
------

Xiaoming Ni (2):
  powerpc:85xx:Fix oops when mpc85xx_smp_guts_ids node cannot be found
  powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n

 arch/powerpc/platforms/85xx/Makefile         |  4 +++-
 arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c |  7 +++++--
 arch/powerpc/platforms/85xx/smp.c            | 12 ++++++------
 3 files changed, 14 insertions(+), 9 deletions(-)

-- 
2.27.0


^ permalink raw reply	[flat|nested] 12+ messages in thread
* [PATCH v2 1/2] powerpc:85xx:Fix oops when mpc85xx_smp_guts_ids node cannot be found
  2021-09-29  3:36     ` Xiaoming Ni
@ 2021-09-29  3:36       ` Xiaoming Ni
  -1 siblings, 0 replies; 12+ messages in thread
From: Xiaoming Ni @ 2021-09-29  3:36 UTC (permalink / raw)
  To: oss, mpe, benh, paulus, paul.gortmaker, chenhui.zhao,
	Yuantian.Tang, linuxppc-dev, linux-kernel, stable, gregkh
  Cc: wangle6, liuwenliang, chenjianguo3, nixiaoming

When the field described in mpc85xx_smp_guts_ids[] is not configured in
 dtb, the mpc85xx_setup_pmc() does not assign a value to the "guts"
 variable. As a result, the oops is triggered when
 mpc85xx_freeze_time_base() is executed.

Fixes:56f1ba280719 ("powerpc/mpc85xx: refactor the PM operations")
Cc: stable@vger.kernel.org #v4.6
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
---
 arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
index 7c0133f558d0..ffa8a7a6a2db 100644
--- a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
+++ b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
@@ -94,9 +94,8 @@ int __init mpc85xx_setup_pmc(void)
 			pr_err("Could not map guts node address\n");
 			return -ENOMEM;
 		}
+		qoriq_pm_ops = &mpc85xx_pm_ops;
 	}
 
-	qoriq_pm_ops = &mpc85xx_pm_ops;
-
 	return 0;
 }
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread
* [PATCH v2 1/2] powerpc:85xx:Fix oops when mpc85xx_smp_guts_ids node cannot be found
@ 2021-09-29  3:36       ` Xiaoming Ni
  0 siblings, 0 replies; 12+ messages in thread
From: Xiaoming Ni @ 2021-09-29  3:36 UTC (permalink / raw)
  To: oss, mpe, benh, paulus, paul.gortmaker, chenhui.zhao,
	Yuantian.Tang, linuxppc-dev, linux-kernel, stable, gregkh
  Cc: liuwenliang, wangle6, nixiaoming, chenjianguo3

When the field described in mpc85xx_smp_guts_ids[] is not configured in
 dtb, the mpc85xx_setup_pmc() does not assign a value to the "guts"
 variable. As a result, the oops is triggered when
 mpc85xx_freeze_time_base() is executed.

Fixes:56f1ba280719 ("powerpc/mpc85xx: refactor the PM operations")
Cc: stable@vger.kernel.org #v4.6
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
---
 arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
index 7c0133f558d0..ffa8a7a6a2db 100644
--- a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
+++ b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
@@ -94,9 +94,8 @@ int __init mpc85xx_setup_pmc(void)
 			pr_err("Could not map guts node address\n");
 			return -ENOMEM;
 		}
+		qoriq_pm_ops = &mpc85xx_pm_ops;
 	}
 
-	qoriq_pm_ops = &mpc85xx_pm_ops;
-
 	return 0;
 }
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread
* [PATCH v2 2/2] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n
  2021-09-29  3:36     ` Xiaoming Ni
@ 2021-09-29  3:36       ` Xiaoming Ni
  -1 siblings, 0 replies; 12+ messages in thread
From: Xiaoming Ni @ 2021-09-29  3:36 UTC (permalink / raw)
  To: oss, mpe, benh, paulus, paul.gortmaker, chenhui.zhao,
	Yuantian.Tang, linuxppc-dev, linux-kernel, stable, gregkh
  Cc: wangle6, liuwenliang, chenjianguo3, nixiaoming

When CONFIG_SMP=y, timebase synchronization is required when the second
 kernel is started.
	arch/powerpc/kernel/smp.c:
	int __cpu_up(unsigned int cpu, struct task_struct *tidle)
	{
		...
		if (smp_ops->give_timebase)
			smp_ops->give_timebase();
		...
	}

	void start_secondary(void *unused)
	{
		...
		if (smp_ops->take_timebase)
			smp_ops->take_timebase();
		...
	}

When CONFIG_HOTPLUG_CPU=n and CONFIG_KEXEC_CORE=n,
 smp_85xx_ops.give_timebase is NULL,
 smp_85xx_ops.take_timebase is NULL,
As a result, the timebase is not synchronized.

Timebase  synchronization does not depend on CONFIG_HOTPLUG_CPU.

Fixes: 56f1ba280719 ("powerpc/mpc85xx: refactor the PM operations")
Cc: stable@vger.kernel.org #v4.6
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
---
 arch/powerpc/platforms/85xx/Makefile         |  4 +++-
 arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c |  4 ++++
 arch/powerpc/platforms/85xx/smp.c            | 12 ++++++------
 3 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/platforms/85xx/Makefile b/arch/powerpc/platforms/85xx/Makefile
index 60e4e97a929d..260fbad7967b 100644
--- a/arch/powerpc/platforms/85xx/Makefile
+++ b/arch/powerpc/platforms/85xx/Makefile
@@ -3,7 +3,9 @@
 # Makefile for the PowerPC 85xx linux kernel.
 #
 obj-$(CONFIG_SMP) += smp.o
-obj-$(CONFIG_FSL_PMC)		  += mpc85xx_pm_ops.o
+ifneq ($(CONFIG_FSL_CORENET_RCPM),y)
+obj-$(CONFIG_SMP) += mpc85xx_pm_ops.o
+endif
 
 obj-y += common.o
 
diff --git a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
index ffa8a7a6a2db..4a8af80011a6 100644
--- a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
+++ b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
@@ -17,6 +17,7 @@
 
 static struct ccsr_guts __iomem *guts;
 
+#ifdef CONFIG_FSL_PMC
 static void mpc85xx_irq_mask(int cpu)
 {
 
@@ -49,6 +50,7 @@ static void mpc85xx_cpu_up_prepare(int cpu)
 {
 
 }
+#endif
 
 static void mpc85xx_freeze_time_base(bool freeze)
 {
@@ -76,10 +78,12 @@ static const struct of_device_id mpc85xx_smp_guts_ids[] = {
 
 static const struct fsl_pm_ops mpc85xx_pm_ops = {
 	.freeze_time_base = mpc85xx_freeze_time_base,
+#ifdef CONFIG_FSL_PMC
 	.irq_mask = mpc85xx_irq_mask,
 	.irq_unmask = mpc85xx_irq_unmask,
 	.cpu_die = mpc85xx_cpu_die,
 	.cpu_up_prepare = mpc85xx_cpu_up_prepare,
+#endif
 };
 
 int __init mpc85xx_setup_pmc(void)
diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
index c6df294054fe..83f4a6389a28 100644
--- a/arch/powerpc/platforms/85xx/smp.c
+++ b/arch/powerpc/platforms/85xx/smp.c
@@ -40,7 +40,6 @@ struct epapr_spin_table {
 	u32	pir;
 };
 
-#ifdef CONFIG_HOTPLUG_CPU
 static u64 timebase;
 static int tb_req;
 static int tb_valid;
@@ -112,6 +111,7 @@ static void mpc85xx_take_timebase(void)
 	local_irq_restore(flags);
 }
 
+#ifdef CONFIG_HOTPLUG_CPU
 static void smp_85xx_cpu_offline_self(void)
 {
 	unsigned int cpu = smp_processor_id();
@@ -495,21 +495,21 @@ void __init mpc85xx_smp_init(void)
 		smp_85xx_ops.probe = NULL;
 	}
 
-#ifdef CONFIG_HOTPLUG_CPU
 #ifdef CONFIG_FSL_CORENET_RCPM
+	/* Assign a value to qoriq_pm_ops on PPC_E500MC */
 	fsl_rcpm_init();
-#endif
-
-#ifdef CONFIG_FSL_PMC
+#else
+	/* Assign a value to qoriq_pm_ops on !PPC_E500MC */
 	mpc85xx_setup_pmc();
 #endif
 	if (qoriq_pm_ops) {
 		smp_85xx_ops.give_timebase = mpc85xx_give_timebase;
 		smp_85xx_ops.take_timebase = mpc85xx_take_timebase;
+#ifdef CONFIG_HOTPLUG_CPU
 		smp_85xx_ops.cpu_offline_self = smp_85xx_cpu_offline_self;
 		smp_85xx_ops.cpu_die = qoriq_cpu_kill;
-	}
 #endif
+	}
 	smp_ops = &smp_85xx_ops;
 
 #ifdef CONFIG_KEXEC_CORE
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread
* [PATCH v2 2/2] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n
@ 2021-09-29  3:36       ` Xiaoming Ni
  0 siblings, 0 replies; 12+ messages in thread
From: Xiaoming Ni @ 2021-09-29  3:36 UTC (permalink / raw)
  To: oss, mpe, benh, paulus, paul.gortmaker, chenhui.zhao,
	Yuantian.Tang, linuxppc-dev, linux-kernel, stable, gregkh
  Cc: liuwenliang, wangle6, nixiaoming, chenjianguo3

When CONFIG_SMP=y, timebase synchronization is required when the second
 kernel is started.
	arch/powerpc/kernel/smp.c:
	int __cpu_up(unsigned int cpu, struct task_struct *tidle)
	{
		...
		if (smp_ops->give_timebase)
			smp_ops->give_timebase();
		...
	}

	void start_secondary(void *unused)
	{
		...
		if (smp_ops->take_timebase)
			smp_ops->take_timebase();
		...
	}

When CONFIG_HOTPLUG_CPU=n and CONFIG_KEXEC_CORE=n,
 smp_85xx_ops.give_timebase is NULL,
 smp_85xx_ops.take_timebase is NULL,
As a result, the timebase is not synchronized.

Timebase  synchronization does not depend on CONFIG_HOTPLUG_CPU.

Fixes: 56f1ba280719 ("powerpc/mpc85xx: refactor the PM operations")
Cc: stable@vger.kernel.org #v4.6
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
---
 arch/powerpc/platforms/85xx/Makefile         |  4 +++-
 arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c |  4 ++++
 arch/powerpc/platforms/85xx/smp.c            | 12 ++++++------
 3 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/platforms/85xx/Makefile b/arch/powerpc/platforms/85xx/Makefile
index 60e4e97a929d..260fbad7967b 100644
--- a/arch/powerpc/platforms/85xx/Makefile
+++ b/arch/powerpc/platforms/85xx/Makefile
@@ -3,7 +3,9 @@
 # Makefile for the PowerPC 85xx linux kernel.
 #
 obj-$(CONFIG_SMP) += smp.o
-obj-$(CONFIG_FSL_PMC)		  += mpc85xx_pm_ops.o
+ifneq ($(CONFIG_FSL_CORENET_RCPM),y)
+obj-$(CONFIG_SMP) += mpc85xx_pm_ops.o
+endif
 
 obj-y += common.o
 
diff --git a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
index ffa8a7a6a2db..4a8af80011a6 100644
--- a/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
+++ b/arch/powerpc/platforms/85xx/mpc85xx_pm_ops.c
@@ -17,6 +17,7 @@
 
 static struct ccsr_guts __iomem *guts;
 
+#ifdef CONFIG_FSL_PMC
 static void mpc85xx_irq_mask(int cpu)
 {
 
@@ -49,6 +50,7 @@ static void mpc85xx_cpu_up_prepare(int cpu)
 {
 
 }
+#endif
 
 static void mpc85xx_freeze_time_base(bool freeze)
 {
@@ -76,10 +78,12 @@ static const struct of_device_id mpc85xx_smp_guts_ids[] = {
 
 static const struct fsl_pm_ops mpc85xx_pm_ops = {
 	.freeze_time_base = mpc85xx_freeze_time_base,
+#ifdef CONFIG_FSL_PMC
 	.irq_mask = mpc85xx_irq_mask,
 	.irq_unmask = mpc85xx_irq_unmask,
 	.cpu_die = mpc85xx_cpu_die,
 	.cpu_up_prepare = mpc85xx_cpu_up_prepare,
+#endif
 };
 
 int __init mpc85xx_setup_pmc(void)
diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
index c6df294054fe..83f4a6389a28 100644
--- a/arch/powerpc/platforms/85xx/smp.c
+++ b/arch/powerpc/platforms/85xx/smp.c
@@ -40,7 +40,6 @@ struct epapr_spin_table {
 	u32	pir;
 };
 
-#ifdef CONFIG_HOTPLUG_CPU
 static u64 timebase;
 static int tb_req;
 static int tb_valid;
@@ -112,6 +111,7 @@ static void mpc85xx_take_timebase(void)
 	local_irq_restore(flags);
 }
 
+#ifdef CONFIG_HOTPLUG_CPU
 static void smp_85xx_cpu_offline_self(void)
 {
 	unsigned int cpu = smp_processor_id();
@@ -495,21 +495,21 @@ void __init mpc85xx_smp_init(void)
 		smp_85xx_ops.probe = NULL;
 	}
 
-#ifdef CONFIG_HOTPLUG_CPU
 #ifdef CONFIG_FSL_CORENET_RCPM
+	/* Assign a value to qoriq_pm_ops on PPC_E500MC */
 	fsl_rcpm_init();
-#endif
-
-#ifdef CONFIG_FSL_PMC
+#else
+	/* Assign a value to qoriq_pm_ops on !PPC_E500MC */
 	mpc85xx_setup_pmc();
 #endif
 	if (qoriq_pm_ops) {
 		smp_85xx_ops.give_timebase = mpc85xx_give_timebase;
 		smp_85xx_ops.take_timebase = mpc85xx_take_timebase;
+#ifdef CONFIG_HOTPLUG_CPU
 		smp_85xx_ops.cpu_offline_self = smp_85xx_cpu_offline_self;
 		smp_85xx_ops.cpu_die = qoriq_cpu_kill;
-	}
 #endif
+	}
 	smp_ops = &smp_85xx_ops;
 
 #ifdef CONFIG_KEXEC_CORE
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 12+ messages in thread
* Re: [PATCH v2 0/2] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n
  2021-09-29  3:36     ` Xiaoming Ni
@ 2021-10-11 12:06       ` Michael Ellerman
  -1 siblings, 0 replies; 12+ messages in thread
From: Michael Ellerman @ 2021-10-11 12:06 UTC (permalink / raw)
  To: paul.gortmaker, linuxppc-dev, mpe, Xiaoming Ni, stable, oss,
	benh, chenhui.zhao, linux-kernel, gregkh, paulus, Yuantian.Tang
  Cc: liuwenliang, chenjianguo3, wangle6

On Wed, 29 Sep 2021 11:36:44 +0800, Xiaoming Ni wrote:
> When CONFIG_SMP=y, timebase synchronization is required for mpc8572 when
>  the second kernel is started
> 	arch/powerpc/kernel/smp.c:
> 	int __cpu_up(unsigned int cpu, struct task_struct *tidle)
> 	{
> 		...
> 		if (smp_ops->give_timebase)
> 			smp_ops->give_timebase();
> 		...
> 	}
> 
> [...]

Applied to powerpc/next.

[1/2] powerpc:85xx:Fix oops when mpc85xx_smp_guts_ids node cannot be found
      https://git.kernel.org/powerpc/c/3c2172c1c47b4079c29f0e6637d764a99355ebcd
[2/2] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n
      https://git.kernel.org/powerpc/c/c45361abb9185b1e172bd75eff51ad5f601ccae4

cheers

^ permalink raw reply	[flat|nested] 12+ messages in thread
* Re: [PATCH v2 0/2] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n
@ 2021-10-11 12:06       ` Michael Ellerman
  0 siblings, 0 replies; 12+ messages in thread
From: Michael Ellerman @ 2021-10-11 12:06 UTC (permalink / raw)
  To: paul.gortmaker, linuxppc-dev, mpe, Xiaoming Ni, stable, oss,
	benh, chenhui.zhao, linux-kernel, gregkh, paulus, Yuantian.Tang
  Cc: liuwenliang, wangle6, chenjianguo3

On Wed, 29 Sep 2021 11:36:44 +0800, Xiaoming Ni wrote:
> When CONFIG_SMP=y, timebase synchronization is required for mpc8572 when
>  the second kernel is started
> 	arch/powerpc/kernel/smp.c:
> 	int __cpu_up(unsigned int cpu, struct task_struct *tidle)
> 	{
> 		...
> 		if (smp_ops->give_timebase)
> 			smp_ops->give_timebase();
> 		...
> 	}
> 
> [...]

Applied to powerpc/next.

[1/2] powerpc:85xx:Fix oops when mpc85xx_smp_guts_ids node cannot be found
      https://git.kernel.org/powerpc/c/3c2172c1c47b4079c29f0e6637d764a99355ebcd
[2/2] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n
      https://git.kernel.org/powerpc/c/c45361abb9185b1e172bd75eff51ad5f601ccae4

cheers

^ permalink raw reply	[flat|nested] 12+ messages in thread
end of thread, other threads:[~2021-10-11 12:12 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-09-26  2:51 [PATCH] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n Xiaoming Ni
2021-09-26  2:51 ` Xiaoming Ni
2021-09-26 12:34 ` Xiaoming Ni
2021-09-26 12:34   ` Xiaoming Ni
2021-09-29  3:36   ` [PATCH v2 0/2] " Xiaoming Ni
2021-09-29  3:36     ` Xiaoming Ni
2021-09-29  3:36     ` [PATCH v2 1/2] powerpc:85xx:Fix oops when mpc85xx_smp_guts_ids node cannot be found Xiaoming Ni
2021-09-29  3:36       ` Xiaoming Ni
2021-09-29  3:36     ` [PATCH v2 2/2] powerpc:85xx: fix timebase sync issue when CONFIG_HOTPLUG_CPU=n Xiaoming Ni
2021-09-29  3:36       ` Xiaoming Ni
2021-10-11 12:06     ` [PATCH v2 0/2] " Michael Ellerman
2021-10-11 12:06       ` Michael Ellerman

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