Re: [PATCH v2 2/2] platform/x86: think-lmi: Clean up display of current_value on Thinkstation

From: Mirsad Goran Todorovac
Date: Mon Apr 03 2023 - 04:22:31 EST


On 3.4.2023. 3:31, Mark Pearson wrote:
On ThinkStations on retrieving the attribute value the BIOS appends the
possible values to the string.
Clean up the display in the current_value_show function so the options
part is not displayed.

Fixes: a40cd7ef22fb ("platform/x86: think-lmi: Add WMI interface support on Lenovo platforms")
Reported by Mario Limoncello <Mario.Limonciello@xxxxxxx>
Link: https://github.com/fwupd/fwupd/issues/5077#issuecomment-1488730526
Signed-off-by: Mark Pearson <mpearson-lenovo@xxxxxxxxx>
---
Changes in v2: For some reason v2 doesn't apply cleanly so rebased and
started again. Hopefully this one works

drivers/platform/x86/think-lmi.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/platform/x86/think-lmi.c b/drivers/platform/x86/think-lmi.c
index 87f832142d8d..78dc82bda4dd 100644
--- a/drivers/platform/x86/think-lmi.c
+++ b/drivers/platform/x86/think-lmi.c
@@ -920,7 +920,7 @@ static ssize_t display_name_show(struct kobject *kobj, struct kobj_attribute *at
static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
{
struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
- char *item, *value;
+ char *item, *value, *p;
int ret;
ret = tlmi_setting(setting->index, &item, LENOVO_BIOS_SETTING_GUID);
@@ -931,9 +931,12 @@ static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *a
value = strpbrk(item, ",");
if (!value || value == item || !strlen(value + 1))
ret = -EINVAL;
- else
+ else {
+ /* On Workstations remove the Options part after the value */
+ p = strchrnul(value, ';');
+ *p = '\0';
ret = sysfs_emit(buf, "%s\n", value + 1);
-
+ }
kfree(item);
return ret;

I can confirm the build against the Torvalds 6.3-rc5 tree and Armin's patch
applied w these.

[root@pc-mtodorov kernel]# uname -rms
Linux 6.3.0-rc5-mt-20230401-00005-g10de4cefccf7 x86_64
[root@pc-mtodorov kernel]# cat /sys/kernel/debug/kmemleak
[root@pc-mtodorov kernel]# echo scan > !$
echo scan > /sys/kernel/debug/kmemleak
[root@pc-mtodorov kernel]# cat /sys/kernel/debug/kmemleak
[root@pc-mtodorov kernel]# echo scan > /sys/kernel/debug/kmemleak
[root@pc-mtodorov kernel]# cat /sys/kernel/debug/kmemleak
[root@pc-mtodorov kernel]# echo scan > /sys/kernel/debug/kmemleak
[root@pc-mtodorov kernel]# cat /sys/kernel/debug/kmemleak
[root@pc-mtodorov kernel]#

The leak is apparently gone in the original setup that reproduced the leak.

At your convenience, you can please add

Tested-by: Mirsad Goran Todorovac <mirsad.todorovac@xxxxxxxxxxxx>

Have a nice day.

Best regards,
Mirsad

--
Mirsad Todorovac
System engineer
Faculty of Graphic Arts | Academy of Fine Arts
University of Zagreb
Republic of Croatia, the European Union

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