[PATCH 0/4] ACPI and PM patches for Euler stable from mainline v3.6

[PATCH 0/4] ACPI and PM patches for Euler stable from mainline v3.6

[Hanjun Guo]

Hi Zefan,

These four patches are bugfix for ACPI and power management from mainline 
v3.6, comments are welcomed!

Thanks
Hanjun Guo


Colin Cross (1):
  cpuidle: fix error handling in __cpuidle_register_device

Stephen Boyd (1):
  cpufreq: Fix sysfs deadlock with concurrent hotplug/frequency switch

Thomas Renninger (2):
  ACPI: Untangle a return statement for better readability
  ACPI: Only count valid srat memory structures

 arch/ia64/kernel/acpi.c   |    5 +++--
 arch/x86/mm/srat.c        |   16 +++++++++-------
 drivers/acpi/numa.c       |   12 ++++++++----
 drivers/cpufreq/cpufreq.c |   35 +++++++++++++++++++++++++++--------
 drivers/cpuidle/cpuidle.c |   13 +++++++++----
 include/linux/acpi.h      |    2 +-
 6 files changed, 57 insertions(+), 26 deletions(-)

[PATCH 1/4] cpuidle: fix error handling in __cpuidle_register_device

[Hanjun Guo]

From: Colin Cross <ccross@android.com>

mainline inclusion
from mainline-3.6
upstream commit 3af272ab75c7a0c7fa5ae5507724d961f7e7718b
category: bugfix

--------------------------------------------------------

Fix the error handling in __cpuidle_register_device to include
the missing list_del.  Move it to a label, which will simplify
the error handling when coupled states are added.

Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Colin Cross <ccross@android.com>
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
Integrated-by: Hanjun Guo <guohanjun@huawei.com>
---
 drivers/cpuidle/cpuidle.c |   13 +++++++++----
 1 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 2f0083a..7407a98 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -387,13 +387,18 @@ static int __cpuidle_register_device(struct cpuidle_device *dev)
 
 	per_cpu(cpuidle_devices, dev->cpu) = dev;
 	list_add(&dev->device_list, &cpuidle_detected_devices);
-	if ((ret = cpuidle_add_sysfs(cpu_dev))) {
-		module_put(cpuidle_driver->owner);
-		return ret;
-	}
+	ret = cpuidle_add_sysfs(cpu_dev);
+	if (ret)
+		goto err_sysfs;
 
 	dev->registered = 1;
 	return 0;
+
+err_sysfs:
+	list_del(&dev->device_list);
+	per_cpu(cpuidle_devices, dev->cpu) = NULL;
+	module_put(cpuidle_driver->owner);
+	return ret;
 }
 
 /**
-- 
1.6.0.2

[PATCH 2/4] cpufreq: Fix sysfs deadlock with concurrent hotplug/frequency switch

[Hanjun Guo]

From: Stephen Boyd <sboyd@codeaurora.org>

mainline inclusion
from mainline-3.6
upstream commit a9144436271583115a2230db15d0b6ae2c481d3c
category: bugfix

As cpu offline/online and DVFS will be used in the actual
production environment, this patch is worth to be backported.

--------------------------------------------------------

Running one program that continuously hotplugs and replugs a cpu
concurrently with another program that continuously writes to the
scaling_setspeed node eventually deadlocks with:

=============================================
[ INFO: possible recursive locking detected ]
3.4.0 #37 Tainted: G        W
---------------------------------------------
filemonkey/122 is trying to acquire lock:
 (s_active#13){++++.+}, at: [<c01a3d28>] sysfs_remove_dir+0x9c/0xb4

but task is already holding lock:
 (s_active#13){++++.+}, at: [<c01a22f0>] sysfs_write_file+0xe8/0x140

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(s_active#13);
  lock(s_active#13);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by filemonkey/122:
 #0:  (&buffer->mutex){+.+.+.}, at: [<c01a2230>] sysfs_write_file+0x28/0x140
 #1:  (s_active#13){++++.+}, at: [<c01a22f0>] sysfs_write_file+0xe8/0x140

stack backtrace:
[<c0014fcc>] (unwind_backtrace+0x0/0x120) from [<c00ca600>] (validate_chain+0x6f8/0x1054)
[<c00ca600>] (validate_chain+0x6f8/0x1054) from [<c00cb778>] (__lock_acquire+0x81c/0x8d8)
[<c00cb778>] (__lock_acquire+0x81c/0x8d8) from [<c00cb9c0>] (lock_acquire+0x18c/0x1e8)
[<c00cb9c0>] (lock_acquire+0x18c/0x1e8) from [<c01a3ba8>] (sysfs_addrm_finish+0xd0/0x180)
[<c01a3ba8>] (sysfs_addrm_finish+0xd0/0x180) from [<c01a3d28>] (sysfs_remove_dir+0x9c/0xb4)
[<c01a3d28>] (sysfs_remove_dir+0x9c/0xb4) from [<c02d0e5c>] (kobject_del+0x10/0x38)
[<c02d0e5c>] (kobject_del+0x10/0x38) from [<c02d0f74>] (kobject_release+0xf0/0x194)
[<c02d0f74>] (kobject_release+0xf0/0x194) from [<c0565a98>] (cpufreq_cpu_put+0xc/0x24)
[<c0565a98>] (cpufreq_cpu_put+0xc/0x24) from [<c05683f0>] (store+0x6c/0x74)
[<c05683f0>] (store+0x6c/0x74) from [<c01a2314>] (sysfs_write_file+0x10c/0x140)
[<c01a2314>] (sysfs_write_file+0x10c/0x140) from [<c014af44>] (vfs_write+0xb0/0x128)
[<c014af44>] (vfs_write+0xb0/0x128) from [<c014b06c>] (sys_write+0x3c/0x68)
[<c014b06c>] (sys_write+0x3c/0x68) from [<c000e0e0>] (ret_fast_syscall+0x0/0x3c)

This is because store() in cpufreq.c indirectly calls
kobject_get() via cpufreq_cpu_get() and is the last one to call
kobject_put() via cpufreq_cpu_put(). Sysfs code should not call
kobject_get() or kobject_put() directly (see the comment around
sysfs_schedule_callback() for more information).

Fix this deadlock by introducing two new functions:

	struct cpufreq_policy *cpufreq_cpu_get_sysfs(unsigned int cpu)
	void cpufreq_cpu_put_sysfs(struct cpufreq_policy *data)

which do the same thing as cpufreq_cpu_{get,put}() but don't call
kobject functions.

To easily trigger this deadlock you can insert an msleep() with a
reasonably large value right after the fail label at the bottom
of the store() function in cpufreq.c and then write
scaling_setspeed in one task and offline the cpu in another. The
first task will hang and be detected by the hung task detector.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Integrated-by: Hanjun Guo <guohanjun@huawei.com>
---
 drivers/cpufreq/cpufreq.c |   35 +++++++++++++++++++++++++++--------
 1 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 7f2f149..fb8a527 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -138,7 +138,7 @@ void disable_cpufreq(void)
 static LIST_HEAD(cpufreq_governor_list);
 static DEFINE_MUTEX(cpufreq_governor_mutex);
 
-struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
+static struct cpufreq_policy *__cpufreq_cpu_get(unsigned int cpu, bool sysfs)
 {
 	struct cpufreq_policy *data;
 	unsigned long flags;
@@ -162,7 +162,7 @@ struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
 	if (!data)
 		goto err_out_put_module;
 
-	if (!kobject_get(&data->kobj))
+	if (!sysfs && !kobject_get(&data->kobj))
 		goto err_out_put_module;
 
 	spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
@@ -175,16 +175,35 @@ err_out_unlock:
 err_out:
 	return NULL;
 }
+
+struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
+{
+	return __cpufreq_cpu_get(cpu, false);
+}
 EXPORT_SYMBOL_GPL(cpufreq_cpu_get);
 
+static struct cpufreq_policy *cpufreq_cpu_get_sysfs(unsigned int cpu)
+{
+	return __cpufreq_cpu_get(cpu, true);
+}
 
-void cpufreq_cpu_put(struct cpufreq_policy *data)
+static void __cpufreq_cpu_put(struct cpufreq_policy *data, bool sysfs)
 {
-	kobject_put(&data->kobj);
+	if (!sysfs)
+		kobject_put(&data->kobj);
 	module_put(cpufreq_driver->owner);
 }
+
+void cpufreq_cpu_put(struct cpufreq_policy *data)
+{
+	__cpufreq_cpu_put(data, false);
+}
 EXPORT_SYMBOL_GPL(cpufreq_cpu_put);
 
+static void cpufreq_cpu_put_sysfs(struct cpufreq_policy *data)
+{
+	__cpufreq_cpu_put(data, true);
+}
 
 /*********************************************************************
  *            EXTERNALLY AFFECTING FREQUENCY CHANGES                 *
@@ -617,7 +636,7 @@ static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
 	struct cpufreq_policy *policy = to_policy(kobj);
 	struct freq_attr *fattr = to_attr(attr);
 	ssize_t ret = -EINVAL;
-	policy = cpufreq_cpu_get(policy->cpu);
+	policy = cpufreq_cpu_get_sysfs(policy->cpu);
 	if (!policy)
 		goto no_policy;
 
@@ -631,7 +650,7 @@ static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
 
 	unlock_policy_rwsem_read(policy->cpu);
 fail:
-	cpufreq_cpu_put(policy);
+	cpufreq_cpu_put_sysfs(policy);
 no_policy:
 	return ret;
 }
@@ -642,7 +661,7 @@ static ssize_t store(struct kobject *kobj, struct attribute *attr,
 	struct cpufreq_policy *policy = to_policy(kobj);
 	struct freq_attr *fattr = to_attr(attr);
 	ssize_t ret = -EINVAL;
-	policy = cpufreq_cpu_get(policy->cpu);
+	policy = cpufreq_cpu_get_sysfs(policy->cpu);
 	if (!policy)
 		goto no_policy;
 
@@ -656,7 +675,7 @@ static ssize_t store(struct kobject *kobj, struct attribute *attr,
 
 	unlock_policy_rwsem_write(policy->cpu);
 fail:
-	cpufreq_cpu_put(policy);
+	cpufreq_cpu_put_sysfs(policy);
 no_policy:
 	return ret;
 }
-- 
1.6.0.2

[PATCH 3/4] ACPI: Untangle a return statement for better readability

[Hanjun Guo]

From: Thomas Renninger <trenn@suse.de>

mainline inclusion
from mainline-3.6
upstream commit f3946fb6e50b750d34f445188fa6746d14596afa
category: cleanup

This patch is cleanup patch, but the next bugfix patch is
upon it.

--------------------------------------------------------

No functional change.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Integrated-by: Hanjun Guo <guohanjun@huawei.com>
---
 drivers/acpi/numa.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa.c
index e56f3be..2a63993 100644
--- a/drivers/acpi/numa.c
+++ b/drivers/acpi/numa.c
@@ -304,8 +304,10 @@ int __init acpi_numa_init(void)
 
 	acpi_numa_arch_fixup();
 
-	if (cnt <= 0)
-		return cnt ?: -ENOENT;
+	if (cnt < 0)
+		return cnt;
+	else if (cnt == 0)
+		return -ENOENT;
 	return 0;
 }
 
-- 
1.6.0.2

[PATCH 4/4] ACPI: Only count valid srat memory structures

[Hanjun Guo]

From: Thomas Renninger <trenn@suse.de>

mainline inclusion
from mainline-3.6
upstream commit 095adbb6441172985f5ddc3b9e88cb3191bdeac4
category: bugfix

If BIOS provide OS with SRAT table which contains only one disabled
memory affinity structure, this will trigger a WARN_ON.

This patch is based on the former one "ACPI: Untangle a return
statement for better readability".

--------------------------------------------------------

Otherwise you could run into:
WARN_ON in numa_register_memblks(), because node_possible_map is zero

References: https://bugzilla.novell.com/show_bug.cgi?id=757888

On this machine (ProLiant ML570 G3) the SRAT table contains:
  - No processor affinities
  - One memory affinity structure (which is set disabled)

CC: Per Jessen <per@opensuse.org>
CC: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Integrated-by: Hanjun Guo <guohanjun@huawei.com>
---
 arch/ia64/kernel/acpi.c |    5 +++--
 arch/x86/mm/srat.c      |   16 +++++++++-------
 drivers/acpi/numa.c     |    8 +++++---
 include/linux/acpi.h    |    2 +-
 4 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/arch/ia64/kernel/acpi.c b/arch/ia64/kernel/acpi.c
index 6f38b61..4405788 100644
--- a/arch/ia64/kernel/acpi.c
+++ b/arch/ia64/kernel/acpi.c
@@ -497,7 +497,7 @@ acpi_numa_processor_affinity_init(struct acpi_srat_cpu_affinity *pa)
 	srat_num_cpus++;
 }
 
-void __init
+int __init
 acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma)
 {
 	unsigned long paddr, size;
@@ -512,7 +512,7 @@ acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma)
 
 	/* Ignore disabled entries */
 	if (!(ma->flags & ACPI_SRAT_MEM_ENABLED))
-		return;
+		return -1;
 
 	/* record this node in proximity bitmap */
 	pxm_bit_set(pxm);
@@ -531,6 +531,7 @@ acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma)
 	p->size = size;
 	p->nid = pxm;
 	num_node_memblks++;
+	return 0;
 }
 
 void __init acpi_numa_arch_fixup(void)
diff --git a/arch/x86/mm/srat.c b/arch/x86/mm/srat.c
index efb5b4b..db870ec 100644
--- a/arch/x86/mm/srat.c
+++ b/arch/x86/mm/srat.c
@@ -142,23 +142,23 @@ static inline int save_add_info(void) {return 0;}
 #endif
 
 /* Callback for parsing of the Proximity Domain <-> Memory Area mappings */
-void __init
+int __init
 acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma)
 {
 	u64 start, end;
 	int node, pxm;
 
 	if (srat_disabled())
-		return;
+		return -1;
 	if (ma->header.length != sizeof(struct acpi_srat_mem_affinity)) {
 		bad_srat();
-		return;
+		return -1;
 	}
 	if ((ma->flags & ACPI_SRAT_MEM_ENABLED) == 0)
-		return;
+		return -1;
 
 	if ((ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) && !save_add_info())
-		return;
+		return -1;
 	start = ma->base_address;
 	end = start + ma->length;
 	pxm = ma->proximity_domain;
@@ -168,16 +168,18 @@ acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma)
 	if (node < 0) {
 		printk(KERN_ERR "SRAT: Too many proximity domains.\n");
 		bad_srat();
-		return;
+		return -1;
 	}
 
 	if (numa_add_memblk(node, start, end) < 0) {
 		bad_srat();
-		return;
+		return -1;
 	}
 
 	printk(KERN_INFO "SRAT: Node %u PXM %u %Lx-%Lx\n", node, pxm,
 	       start, end);
+  
+	return 0;
 }
 
 void __init acpi_numa_arch_fixup(void) {}
diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa.c
index 2a63993..cb31298 100644
--- a/drivers/acpi/numa.c
+++ b/drivers/acpi/numa.c
@@ -237,6 +237,8 @@ acpi_parse_processor_affinity(struct acpi_subtable_header *header,
 	return 0;
 }
 
+static int __initdata parsed_numa_memblks;
+
 static int __init
 acpi_parse_memory_affinity(struct acpi_subtable_header * header,
 			   const unsigned long end)
@@ -250,8 +252,8 @@ acpi_parse_memory_affinity(struct acpi_subtable_header * header,
 	acpi_table_print_srat_entry(header);
 
 	/* let architecture-dependent part to do it */
-	acpi_numa_memory_affinity_init(memory_affinity);
-
+	if (!acpi_numa_memory_affinity_init(memory_affinity))
+		parsed_numa_memblks++;
 	return 0;
 }
 
@@ -306,7 +308,7 @@ int __init acpi_numa_init(void)
 
 	if (cnt < 0)
 		return cnt;
-	else if (cnt == 0)
+	else if (!parsed_numa_memblks)
 		return -ENOENT;
 	return 0;
 }
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index f421dd8..8b88441 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -96,7 +96,7 @@ void acpi_table_print_madt_entry (struct acpi_subtable_header *madt);
 void acpi_numa_slit_init (struct acpi_table_slit *slit);
 void acpi_numa_processor_affinity_init (struct acpi_srat_cpu_affinity *pa);
 void acpi_numa_x2apic_affinity_init(struct acpi_srat_x2apic_cpu_affinity *pa);
-void acpi_numa_memory_affinity_init (struct acpi_srat_mem_affinity *ma);
+int acpi_numa_memory_affinity_init (struct acpi_srat_mem_affinity *ma);
 void acpi_numa_arch_fixup(void);
 
 #ifdef CONFIG_ACPI_HOTPLUG_CPU
-- 
1.6.0.2

Re: [PATCH 0/4] ACPI and PM patches for Euler stable from mainline v3.6

[Hanjun Guo]

I made a mistake in sending email, sorry for the bothering, please ignore it.

On 2013/4/10 18:22, Hanjun Guo wrote:
> Hi Zefan,
> 
> These four patches are bugfix for ACPI and power management from mainline 
> v3.6, comments are welcomed!
> 
> Thanks
> Hanjun Guo
> 
> 
> Colin Cross (1):
>   cpuidle: fix error handling in __cpuidle_register_device
> 
> Stephen Boyd (1):
>   cpufreq: Fix sysfs deadlock with concurrent hotplug/frequency switch
> 
> Thomas Renninger (2):
>   ACPI: Untangle a return statement for better readability
>   ACPI: Only count valid srat memory structures
> 
>  arch/ia64/kernel/acpi.c   |    5 +++--
>  arch/x86/mm/srat.c        |   16 +++++++++-------
>  drivers/acpi/numa.c       |   12 ++++++++----
>  drivers/cpufreq/cpufreq.c |   35 +++++++++++++++++++++++++++--------
>  drivers/cpuidle/cpuidle.c |   13 +++++++++----
>  include/linux/acpi.h      |    2 +-
>  6 files changed, 57 insertions(+), 26 deletions(-)
> 
> 
> _______________________________________________
> Kernel.openeuler mailing list
> Kernel.openeuler@huawei.com
> http://rnd-openeuler.huawei.com/mailman/listinfo/kernel.openeuler
> 
>