6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Zhang Rui <rui.zhang@xxxxxxxxx>
[ Upstream commit fdaf0c8629d4524a168cb9e4ad4231875749b28c ]
Before commit 7108b80a542b ("hwmon/coretemp: Handle large core ID
value"), there is a fixed mapping between
1. cpu_core_id
2. the index in pdata->core_data[] array
3. the sysfs attr name, aka "tempX_"
The later two always equal cpu_core_id + 2.
After the commit, pdata->core_data[] index is got from ida so that it
can handle sparse core ids and support more cores within a package.
However, the commit erroneously maps the sysfs attr name to
pdata->core_data[] index instead of cpu_core_id + 2.
As a result, the code is not aligned with the comments, and brings user
visible changes in hwmon sysfs on systems with sparse core id.
For example, before commit 7108b80a542b ("hwmon/coretemp: Handle large
core ID value"),
/sys/class/hwmon/hwmon2/temp2_label:Core 0
/sys/class/hwmon/hwmon2/temp3_label:Core 1
/sys/class/hwmon/hwmon2/temp4_label:Core 2
/sys/class/hwmon/hwmon2/temp5_label:Core 3
/sys/class/hwmon/hwmon2/temp6_label:Core 4
/sys/class/hwmon/hwmon3/temp10_label:Core 8
/sys/class/hwmon/hwmon3/temp11_label:Core 9
after commit,
/sys/class/hwmon/hwmon2/temp2_label:Core 0
/sys/class/hwmon/hwmon2/temp3_label:Core 1
/sys/class/hwmon/hwmon2/temp4_label:Core 2
/sys/class/hwmon/hwmon2/temp5_label:Core 3
/sys/class/hwmon/hwmon2/temp6_label:Core 4
/sys/class/hwmon/hwmon2/temp7_label:Core 8
/sys/class/hwmon/hwmon2/temp8_label:Core 9
Restore the previous behavior and rework the code, comments and variable
names to avoid future confusions.
Fixes: 7108b80a542b ("hwmon/coretemp: Handle large core ID value")
Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx>
Link: https://lore.kernel.org/r/20240202092144.71180-3-rui.zhang@xxxxxxxxx
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/hwmon/coretemp.c | 32 +++++++++++++++++++-------------
1 file changed, 19 insertions(+), 13 deletions(-)
diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
index e78c76919111..95f4c0b00b2d 100644
--- a/drivers/hwmon/coretemp.c
+++ b/drivers/hwmon/coretemp.c
@@ -419,7 +419,7 @@ static ssize_t show_temp(struct device *dev,
}
static int create_core_attrs(struct temp_data *tdata, struct device *dev,
- int attr_no)
+ int index)
{
int i;
static ssize_t (*const rd_ptr[TOTAL_ATTRS]) (struct device *dev,
@@ -431,13 +431,20 @@ static int create_core_attrs(struct temp_data *tdata, struct device *dev,
};
for (i = 0; i < tdata->attr_size; i++) {
+ /*
+ * We map the attr number to core id of the CPU
+ * The attr number is always core id + 2
+ * The Pkgtemp will always show up as temp1_*, if available
+ */
+ int attr_no = tdata->is_pkg_data ? 1 : tdata->cpu_core_id + 2;
+
snprintf(tdata->attr_name[i], CORETEMP_NAME_LENGTH,
"temp%d_%s", attr_no, suffixes[i]);
sysfs_attr_init(&tdata->sd_attrs[i].dev_attr.attr);
tdata->sd_attrs[i].dev_attr.attr.name = tdata->attr_name[i];
tdata->sd_attrs[i].dev_attr.attr.mode = 0444;
tdata->sd_attrs[i].dev_attr.show = rd_ptr[i];
- tdata->sd_attrs[i].index = attr_no;
+ tdata->sd_attrs[i].index = index;
tdata->attrs[i] = &tdata->sd_attrs[i].dev_attr.attr;
}
tdata->attr_group.attrs = tdata->attrs;
@@ -495,26 +502,25 @@ static int create_core_data(struct platform_device *pdev, unsigned int cpu,
struct platform_data *pdata = platform_get_drvdata(pdev);
struct cpuinfo_x86 *c = &cpu_data(cpu);
u32 eax, edx;
- int err, index, attr_no;
+ int err, index;
if (!housekeeping_cpu(cpu, HK_TYPE_MISC))
return 0;
/*
- * Find attr number for sysfs:
- * We map the attr number to core id of the CPU
- * The attr number is always core id + 2
- * The Pkgtemp will always show up as temp1_*, if available
+ * Get the index of tdata in pdata->core_data[]
+ * tdata for package: pdata->core_data[1]
+ * tdata for core: pdata->core_data[2] .. pdata->core_data[NUM_REAL_CORES + 1]
*/
if (pkg_flag) {
- attr_no = PKG_SYSFS_ATTR_NO;
+ index = PKG_SYSFS_ATTR_NO;
} else {
index = ida_alloc_max(&pdata->ida, NUM_REAL_CORES - 1, GFP_KERNEL);
if (index < 0)
return index;
pdata->cpu_map[index] = topology_core_id(cpu);
- attr_no = index + BASE_SYSFS_ATTR_NO;
+ index += BASE_SYSFS_ATTR_NO;
}
tdata = init_temp_data(cpu, pkg_flag);
@@ -540,20 +546,20 @@ static int create_core_data(struct platform_device *pdev, unsigned int cpu,
if (get_ttarget(tdata, &pdev->dev) >= 0)
tdata->attr_size++;
- pdata->core_data[attr_no] = tdata;
+ pdata->core_data[index] = tdata;
/* Create sysfs interfaces */
- err = create_core_attrs(tdata, pdata->hwmon_dev, attr_no);
+ err = create_core_attrs(tdata, pdata->hwmon_dev, index);
if (err)
goto exit_free;
return 0;
exit_free:
- pdata->core_data[attr_no] = NULL;
+ pdata->core_data[index] = NULL;
kfree(tdata);
ida_free:
if (!pkg_flag)
- ida_free(&pdata->ida, index);
+ ida_free(&pdata->ida, index - BASE_SYSFS_ATTR_NO);
return err;
}
--
2.43.0
