Hi All, I have built a kernel module against a 4.9.2 for arm board. while inserting this kernel module I am getting below message which is high lighted in red color what exactly mean loading out-of-tree module. what could be the possible reason to get this message? Please help me out to understand below message mean. ubuntu@ubuntu-armhf:/home/Madhu/i2c$ dmesg [ 704.283100] i2c_client: loading out-of-tree module taints kernel. [ 704.285359] driver initialization [ 704.285693] inside probe function Regards, Madhu
On Sat, Feb 11, 2017 at 3:28 PM, Madhu K <madhu.sk89@gmail.com> wrote:
Hi All,
I have built a kernel module against a 4.9.2 for arm board. while inserting this kernel module I am getting below message which is high lighted in red color what exactly mean loading out-of-tree module. what could be the possible reason to get this message?
Please help me out to understand below message mean.
ubuntu@ubuntu-armhf:/home/Madhu/i2c$ dmesg [ 704.283100] i2c_client: loading out-of-tree module taints kernel. [ 704.285359] driver initialization [ 704.285693] inside probe function
Regards, Madhu
_______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
An 'out-of-tree' message does not indicate an error. It is informing you that the module being loaded is not a part of the kernel source tree, but an 'out-of-tree' one, i.e. your custom module whose source code resides say in your home directory. To verify your module has been loaded successfully, run 'lsmod | grep your_module_name' after loading it with 'insmod'. Hope this helps.
Hi Alexander, Thank you so much for your valuable reply. yes, you are correct I have kernel-source in home directory and I did not install modules. To fix "out-of-tree" one, if I do make modules and modules_install will it go off? Thanks, Madhu On Sat, Feb 11, 2017 at 7:27 PM, Alexander Kapshuk < alexander.kapshuk@gmail.com> wrote:
On Sat, Feb 11, 2017 at 3:28 PM, Madhu K <madhu.sk89@gmail.com> wrote:
Hi All,
I have built a kernel module against a 4.9.2 for arm board. while inserting this kernel module I am getting below message which is high lighted in red color what exactly mean loading out-of-tree module. what could be the possible reason to get this message?
Please help me out to understand below message mean.
ubuntu@ubuntu-armhf:/home/Madhu/i2c$ dmesg [ 704.283100] i2c_client: loading out-of-tree module taints kernel. [ 704.285359] driver initialization [ 704.285693] inside probe function
Regards, Madhu
_______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
An 'out-of-tree' message does not indicate an error. It is informing you that the module being loaded is not a part of the kernel source tree, but an 'out-of-tree' one, i.e. your custom module whose source code resides say in your home directory.
To verify your module has been loaded successfully, run 'lsmod | grep your_module_name' after loading it with 'insmod'.
Hope this helps.
On Sat, Feb 11, 2017 at 6:32 PM, Madhu K <madhu.sk89@gmail.com> wrote:
Hi Alexander,
Thank you so much for your valuable reply.
yes, you are correct I have kernel-source in home directory and I did not install modules.
To fix "out-of-tree" one, if I do make modules and modules_install will it go off?
Thanks, Madhu
On Sat, Feb 11, 2017 at 7:27 PM, Alexander Kapshuk <alexander.kapshuk@gmail.com> wrote:
On Sat, Feb 11, 2017 at 3:28 PM, Madhu K <madhu.sk89@gmail.com> wrote:
Hi All,
I have built a kernel module against a 4.9.2 for arm board. while inserting this kernel module I am getting below message which is high lighted in red color what exactly mean loading out-of-tree module. what could be the possible reason to get this message?
Please help me out to understand below message mean.
ubuntu@ubuntu-armhf:/home/Madhu/i2c$ dmesg [ 704.283100] i2c_client: loading out-of-tree module taints kernel. [ 704.285359] driver initialization [ 704.285693] inside probe function
Regards, Madhu
_______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
An 'out-of-tree' message does not indicate an error. It is informing you that the module being loaded is not a part of the kernel source tree, but an 'out-of-tree' one, i.e. your custom module whose source code resides say in your home directory.
To verify your module has been loaded successfully, run 'lsmod | grep your_module_name' after loading it with 'insmod'.
Hope this helps.
You're welcome. Please do not top-post. As I already mentioned, the purpose of the 'loading out-of-tree module taints kernel' message is to inform the users of the i2c_client driver that it is not a part of the kernel source tree. It does not indicate a problem. So, to the best of my knowledge, the message won't go away.
<snip>
Please help me out to understand below message mean.
ubuntu@ubuntu-armhf:/home/Madhu/i2c$ dmesg [ 704.283100] i2c_client: loading out-of-tree module taints kernel. [ 704.285359] driver initialization [ 704.285693] inside probe function
What you should pay attention to more than worry about the out-of-tree module is the text immediately following that. Says "taints kernel" right ? What exactly that means is if you have problems later on with this kernel and require debugging or community support to identify then resolve a bug there will be no community support. When the kernel is tainted, it means that *it is in a state that is not supported by the community*. Most kernel developers will ignore bug reports involving tainted kernels, and community members may ask that you correct the tainting condition before they can proceed with diagnosing problems related to the kernel. In addition, some debugging functionality and API calls may be disabled when the kernel is tainted. [ reference: http://unix.stackexchange.com/questions/118116/linux-what-is-a-tainted-kerne... ] The primary reason for the *‘Tainted: ‘* string is to tell kernel debuggers if this is a clean kernel or if anything unusual has occurred. Tainting is permanent: even if an offending module is unloaded, the tainted value remains to indicate that the kernel is not trustworthy. [ reference: https://www.kernel.org/doc/html/latest/admin-guide/tainted-kernels.html?high... ] Looking at your dmesg output you posted your module initialized ok and your probe was called ok but if shit happens down the road your on your own. Meaning if you ask for help most folks will ask you to fix the taint issue before taking a look at your code :) Hope this helps - Aruna
Regards, Madhu
_______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Hi Aruna, Thank you so much for your information, Thanks, Madhu On Sat, Feb 11, 2017 at 9:15 PM, Aruna Hewapathirane < aruna.hewapathirane@gmail.com> wrote:
<snip>
Please help me out to understand below message mean.
ubuntu@ubuntu-armhf:/home/Madhu/i2c$ dmesg [ 704.283100] i2c_client: loading out-of-tree module taints kernel. [ 704.285359] driver initialization [ 704.285693] inside probe function
What you should pay attention to more than worry about the out-of-tree module is the text immediately following that. Says "taints kernel" right ? What exactly that means is if you have problems later on with this kernel and require debugging or community support to identify then resolve a bug there will be no community support.
When the kernel is tainted, it means that *it is in a state that is not supported by the community*. Most kernel developers will ignore bug reports involving tainted kernels, and community members may ask that you correct the tainting condition before they can proceed with diagnosing problems related to the kernel. In addition, some debugging functionality and API calls may be disabled when the kernel is tainted. [ reference: http://unix.stackexchange.com/questions/118116/linux-what- is-a-tainted-kernel ]
The primary reason for the *‘Tainted: ‘* string is to tell kernel debuggers if this is a clean kernel or if anything unusual has occurred. Tainting is permanent: even if an offending module is unloaded, the tainted value remains to indicate that the kernel is not trustworthy. [ reference: https://www.kernel.org/doc/html/latest/admin-guide/ tainted-kernels.html?highlight=tainted ]
Looking at your dmesg output you posted your module initialized ok and your probe was called ok but if shit happens down the road your on your own. Meaning if you ask for help most folks will ask you to fix the taint issue before taking a look at your code :)
Hope this helps - Aruna
Regards, Madhu
_______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
participants (3)
-
Alexander Kapshuk -
Aruna Hewapathirane -
Madhu K