[PATCH] hwmon: (coretemp) remove duplicated coretemp for same core id

[shuwang@redhat.com]

From: Shu Wang <shuwang@redhat.com>

Fix kernel warning on my 4cpus 2core_id system. The cpu0 and cpu1 have
same core_id 0, so both cpu0 and cpu1 will try to create file temp2_label
when it's online.

- coretemp_cpu_online(cpu=0)
  - create_core_data(cpu=0, attr_no=2)
   - create_core_attrs(attr_no=2)
- coretemp_cpu_online(cpu=1)
  - create_core_data(cpu=1, attr_no=2)
   - create_core_attrs(attr_no=2)

$ grep -e processor -e 'core id' /proc/cpuinfo
processor       : 0
core id         : 0
processor       : 1
core id         : 0
processor       : 2
core id         : 1
processor       : 3
core id         : 1

dmesg:
sysfs: cannot create duplicate filename '/devices/platform/coretemp.0/hwmon/hwmon3/temp2_label'
sysfs: cannot create duplicate filename '/devices/platform/coretemp.0/hwmon/hwmon3/temp3_label'
WARNING: CPU: 3 PID: 27 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x58/0x70
Call Trace:
 sysfs_add_file_mode_ns+0x170/0x180
 internal_create_group+0xe3/0x2c0
 sysfs_create_group+0x13/0x20
 create_core_data+0x3ab/0x5e0 [coretemp]
 coretemp_cpu_online+0x14b/0x1f7 [coretemp]
 ? create_core_data+0x5e0/0x5e0 [coretemp]
 cpuhp_invoke_callback+0xae/0x5c0
 ? __schedule+0x295/0x880
 cpuhp_thread_fun+0xcb/0x170
 smpboot_thread_fn+0x110/0x160

Signed-off-by: Shu Wang <shuwang@redhat.com>
---
 drivers/hwmon/coretemp.c | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
index c13a4fd86b3c..2fb29ab1080b 100644
--- a/drivers/hwmon/coretemp.c
+++ b/drivers/hwmon/coretemp.c
@@ -459,6 +459,17 @@ static struct temp_data *init_temp_data(unsigned int cpu, int pkg_flag)
 	return tdata;
 }
 
+static void coretemp_remove_core(struct platform_data *pdata, int indx)
+{
+	struct temp_data *tdata = pdata->core_data[indx];
+
+	/* Remove the sysfs attributes */
+	sysfs_remove_group(&pdata->hwmon_dev->kobj, &tdata->attr_group);
+
+	kfree(pdata->core_data[indx]);
+	pdata->core_data[indx] = NULL;
+}
+
 static int create_core_data(struct platform_device *pdev, unsigned int cpu,
 			    int pkg_flag)
 {
@@ -479,6 +490,10 @@ static int create_core_data(struct platform_device *pdev, unsigned int cpu,
 	if (attr_no > MAX_CORE_DATA - 1)
 		return -ERANGE;
 
+	tdata = pdata->core_data[attr_no];
+	if (tdata != NULL)
+		coretemp_remove_core(pdata, attr_no);
+
 	tdata = init_temp_data(cpu, pkg_flag);
 	if (!tdata)
 		return -ENOMEM;
@@ -527,17 +542,6 @@ coretemp_add_core(struct platform_device *pdev, unsigned int cpu, int pkg_flag)
 		dev_err(&pdev->dev, "Adding Core %u failed\n", cpu);
 }
 
-static void coretemp_remove_core(struct platform_data *pdata, int indx)
-{
-	struct temp_data *tdata = pdata->core_data[indx];
-
-	/* Remove the sysfs attributes */
-	sysfs_remove_group(&pdata->hwmon_dev->kobj, &tdata->attr_group);
-
-	kfree(pdata->core_data[indx]);
-	pdata->core_data[indx] = NULL;
-}
-
 static int coretemp_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
-- 
2.13.5