[PATCH] platform/x86: think-lmi: Fix "Call Trace" error warning

[PATCH] platform/x86: think-lmi: Fix "Call Trace" error warning

[goutongchen]

From: goutongchen <goutongchen@uniontech.com>

The maximum BIOS password length returned by the Lenovo platform BIOS/WMI
exceeded the size assumed by the think_lmi driver's internal static
buffer, causing the driver to trigger a WARN_ON() during self-checks.

Increase TLMI_PWD_BUFSIZE from 128 to 256 to eliminate the recurring
Call Trace warnings.

Here is the kernel warning triggered by the bug:

  kernel: WARNING: CPU: 4 PID: 665 at drivers/platform/x86/think-lmi.c:326
  kernel:        tlmi_get_pwd_settings.constprop.0+0xe6/0x130 [think_lmi]
  kernel: Call Trace:
  kernel:  tlmi_analyze+0x31c/0x640 [think_lmi]
  ...

Fixes: 651b57dd4087 ("platform/x86: Move Lenovo files into lenovo subdir")
Signed-off-by: goutongchen <goutongchen@uniontech.com>
---
 drivers/platform/x86/lenovo/think-lmi.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/platform/x86/lenovo/think-lmi.h b/drivers/platform/x86/lenovo/think-lmi.h
index 017644323d46..d643cf3b81b0 100644
--- a/drivers/platform/x86/lenovo/think-lmi.h
+++ b/drivers/platform/x86/lenovo/think-lmi.h
@@ -8,7 +8,7 @@
 
 #define TLMI_SETTINGS_COUNT  256
 #define TLMI_SETTINGS_MAXLEN 512
-#define TLMI_PWD_BUFSIZE     129
+#define TLMI_PWD_BUFSIZE     256
 #define TLMI_LANG_MAXLEN       4
 #define TLMI_INDEX_MAX        32
 
-- 
2.20.1

Re: [PATCH] platform/x86: think-lmi: Fix "Call Trace" error warning

[Mark Pearson]

Hi

On Tue, Jul 7, 2026, at 5:15 AM, goutongchen@uniontech.com wrote:
> From: goutongchen <goutongchen@uniontech.com>
>
> The maximum BIOS password length returned by the Lenovo platform BIOS/WMI
> exceeded the size assumed by the think_lmi driver's internal static
> buffer, causing the driver to trigger a WARN_ON() during self-checks.
>
> Increase TLMI_PWD_BUFSIZE from 128 to 256 to eliminate the recurring
> Call Trace warnings.
>
> Here is the kernel warning triggered by the bug:
>
>   kernel: WARNING: CPU: 4 PID: 665 at drivers/platform/x86/think-lmi.c:326
>   kernel:        tlmi_get_pwd_settings.constprop.0+0xe6/0x130 [think_lmi]
>   kernel: Call Trace:
>   kernel:  tlmi_analyze+0x31c/0x640 [think_lmi]
>   ...
>
> Fixes: 651b57dd4087 ("platform/x86: Move Lenovo files into lenovo subdir")

Minor - but I don't think this is really the culprit :)

> Signed-off-by: goutongchen <goutongchen@uniontech.com>
> ---
>  drivers/platform/x86/lenovo/think-lmi.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/platform/x86/lenovo/think-lmi.h 
> b/drivers/platform/x86/lenovo/think-lmi.h
> index 017644323d46..d643cf3b81b0 100644
> --- a/drivers/platform/x86/lenovo/think-lmi.h
> +++ b/drivers/platform/x86/lenovo/think-lmi.h
> @@ -8,7 +8,7 @@
> 
>  #define TLMI_SETTINGS_COUNT  256
>  #define TLMI_SETTINGS_MAXLEN 512
> -#define TLMI_PWD_BUFSIZE     129
> +#define TLMI_PWD_BUFSIZE     256
>  #define TLMI_LANG_MAXLEN       4
>  #define TLMI_INDEX_MAX        32
> 
> -- 
> 2.20.1

Which platform are you seeing this on please? The maxlen for passwords from the BIOS is supposed to be 128 so I'm intrigued as to where you're seeing different. It maybe should be fixed in a platform BIOS?

Mark

Re: [PATCH] platform/x86: think-lmi: Fix "Call Trace" error warning

[Andy Shevchenko]

On Tue, Jul 07, 2026 at 05:15:55PM +0800, goutongchen@uniontech.com wrote:
> From: goutongchen <goutongchen@uniontech.com>

Use your real name and not an alias.

> The maximum BIOS password length returned by the Lenovo platform BIOS/WMI

Which platform? We need more details about the BIOS/HW.

> exceeded the size assumed by the think_lmi driver's internal static
> buffer, causing the driver to trigger a WARN_ON() during self-checks.
> 
> Increase TLMI_PWD_BUFSIZE from 128 to 256 to eliminate the recurring
> Call Trace warnings.
> 
> Here is the kernel warning triggered by the bug:
> 
>   kernel: WARNING: CPU: 4 PID: 665 at drivers/platform/x86/think-lmi.c:326
>   kernel:        tlmi_get_pwd_settings.constprop.0+0xe6/0x130 [think_lmi]
>   kernel: Call Trace:
>   kernel:  tlmi_analyze+0x31c/0x640 [think_lmi]
>   ...

> Fixes: 651b57dd4087 ("platform/x86: Move Lenovo files into lenovo subdir")
> Signed-off-by: goutongchen <goutongchen@uniontech.com>

Ditto.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH] platform/x86: think-lmi: Fix "Call Trace" error warning

[Gou Tongchen]

On 7/7/26 21:31, Mark Pearson wrote:
Hi
> Hi
>
> On Tue, Jul 7, 2026, at 5:15 AM, goutongchen@uniontech.com wrote:
>> From: goutongchen <goutongchen@uniontech.com>
>>
>> The maximum BIOS password length returned by the Lenovo platform BIOS/WMI
>> exceeded the size assumed by the think_lmi driver's internal static
>> buffer, causing the driver to trigger a WARN_ON() during self-checks.
>>
>> Increase TLMI_PWD_BUFSIZE from 128 to 256 to eliminate the recurring
>> Call Trace warnings.
>>
>> Here is the kernel warning triggered by the bug:
>>
>>    kernel: WARNING: CPU: 4 PID: 665 at drivers/platform/x86/think-lmi.c:326
>>    kernel:        tlmi_get_pwd_settings.constprop.0+0xe6/0x130 [think_lmi]
>>    kernel: Call Trace:
>>    kernel:  tlmi_analyze+0x31c/0x640 [think_lmi]
>>    ...
>>
>> Fixes: 651b57dd4087 ("platform/x86: Move Lenovo files into lenovo subdir")
> Minor - but I don't think this is really the culprit :)
Gou Tongchen - Because it was initially discovered on an older kernel 
version, the path hadn't been changed at that time.
>
>> Signed-off-by: goutongchen <goutongchen@uniontech.com>
>> ---
>>   drivers/platform/x86/lenovo/think-lmi.h | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/platform/x86/lenovo/think-lmi.h
>> b/drivers/platform/x86/lenovo/think-lmi.h
>> index 017644323d46..d643cf3b81b0 100644
>> --- a/drivers/platform/x86/lenovo/think-lmi.h
>> +++ b/drivers/platform/x86/lenovo/think-lmi.h
>> @@ -8,7 +8,7 @@
>>
>>   #define TLMI_SETTINGS_COUNT  256
>>   #define TLMI_SETTINGS_MAXLEN 512
>> -#define TLMI_PWD_BUFSIZE     129
>> +#define TLMI_PWD_BUFSIZE     256
>>   #define TLMI_LANG_MAXLEN       4
>>   #define TLMI_INDEX_MAX        32
>>
>> -- 
>> 2.20.1
> Which platform are you seeing this on please? The maxlen for passwords from the BIOS is supposed to be 128 so I'm intrigued as to where you're seeing different. It maybe should be fixed in a platform BIOS?
>
> Mark

The hardware platform is a Lenovo X7h with a Hygon 4 CPU. The specific model and BIOS version are as follows:

kernel: DMI: KaiTian /LXKT-HG4M-X7, BIOS W0WKT1FA 11/18/2025

I found through kernel log printing that the BIOS returned a password length of 255, so I increased TLMI_PWD_BUFSIZE to 256.

Thanks.

Gou Tongchen

>

Re: [PATCH] platform/x86: think-lmi: Fix "Call Trace" error warning

[Ilpo Järvinen]

[-- Attachment #1: Type: text/plain, Size: 2974 bytes --]

On Wed, 8 Jul 2026, Gou Tongchen wrote:
> On 7/7/26 21:31, Mark Pearson wrote:
> > On Tue, Jul 7, 2026, at 5:15 AM, goutongchen@uniontech.com wrote:
> > > From: goutongchen <goutongchen@uniontech.com>
> > > 
> > > The maximum BIOS password length returned by the Lenovo platform BIOS/WMI
> > > exceeded the size assumed by the think_lmi driver's internal static
> > > buffer, causing the driver to trigger a WARN_ON() during self-checks.
> > > 
> > > Increase TLMI_PWD_BUFSIZE from 128 to 256 to eliminate the recurring
> > > Call Trace warnings.
> > > 
> > > Here is the kernel warning triggered by the bug:
> > > 
> > >    kernel: WARNING: CPU: 4 PID: 665 at
> > > drivers/platform/x86/think-lmi.c:326
> > >    kernel:        tlmi_get_pwd_settings.constprop.0+0xe6/0x130 [think_lmi]
> > >    kernel: Call Trace:
> > >    kernel:  tlmi_analyze+0x31c/0x640 [think_lmi]
> > >    ...
> > > 
> > > Fixes: 651b57dd4087 ("platform/x86: Move Lenovo files into lenovo subdir")
> > Minor - but I don't think this is really the culprit :)
>
> Gou Tongchen - Because it was initially discovered on an older kernel version,
> the path hadn't been changed at that time.

Please try to find the commit past that. You can use e.g.

git annotate 651b57dd4087^

to start annotating from right before that commit.

> > > Signed-off-by: goutongchen <goutongchen@uniontech.com>
> > > ---
> > >   drivers/platform/x86/lenovo/think-lmi.h | 2 +-
> > >   1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/platform/x86/lenovo/think-lmi.h
> > > b/drivers/platform/x86/lenovo/think-lmi.h
> > > index 017644323d46..d643cf3b81b0 100644
> > > --- a/drivers/platform/x86/lenovo/think-lmi.h
> > > +++ b/drivers/platform/x86/lenovo/think-lmi.h
> > > @@ -8,7 +8,7 @@
> > > 
> > >   #define TLMI_SETTINGS_COUNT  256
> > >   #define TLMI_SETTINGS_MAXLEN 512
> > > -#define TLMI_PWD_BUFSIZE     129
> > > +#define TLMI_PWD_BUFSIZE     256
> > >   #define TLMI_LANG_MAXLEN       4
> > >   #define TLMI_INDEX_MAX        32
> > > 
> > > -- 
> > > 2.20.1
> > Which platform are you seeing this on please? The maxlen for passwords from
> > the BIOS is supposed to be 128 so I'm intrigued as to where you're seeing
> > different. It maybe should be fixed in a platform BIOS?
> > 
> > Mark
> 
> The hardware platform is a Lenovo X7h with a Hygon 4 CPU. The specific
> model and BIOS version are as follows:
>
> kernel: DMI: KaiTian /LXKT-HG4M-X7, BIOS W0WKT1FA 11/18/2025

This kind of information should be in the changelog, but lets wait a bit 
if Mark wants to check this internally.

We'll probably need to make this change anyway to avoid triggering 
the WARN_ON() even if it would be fixed by some version of the BIOS.

> I found through kernel log printing that the BIOS returned a password
> length of 255, so I increased TLMI_PWD_BUFSIZE to 256.


-- 
 i.