One in a series of columns in which questions are asked of a kernel
developer and he tries to answer them. If you have unanswered questions
relating to technical or procedural things around Linux kernel
development, ask them in the comment section, or email them directly to
How do I open an effective communication channel with a kernel developer
to get my issues fixed?
Despite the size of most kernel subsystem maintainer's inbox, this is a
question that comes up a lot in conversations with users, so it is good
to get it out there.
The easiest way to communicate with a kernel developer about a problem
is to write an email and send it to the subsystem list that handles the
area in which you are having problems, and to copy the developers as
well to make sure that they see the message.
Ah, but how do you figure out what subsystem or mailing list to use?
Luckily the kernel contains a list of the mailing lists and the
developers responsible for the different kernel subsystems. The file,
MAINTAINERS in the Linux kernel source tree, lists all of the
different subsystems, the name of the maintainer, the email address, and
the mailing list that is the best place to bring up things on. If there
is no mailing list specified, then use the default linux-kernel mailing
If you narrow the problem down to a file that you are having questions
about, the script scripts/get_maintainer.pl in the kernel
source tree can find the proper people responsible for changing it
last, as well as any maintainer and mailing lists automatically.
For example, suppose you have a problem with the ftdi_sio driver, which
is located in drivers/usb/serial/ftdio_sio.c. By
running the get_maintainer.pl script with the -f
option, you would get the following:
$ scripts/get_maintainer.pl -f drivers/usb/serial/ftdi_sio.c
Greg Kroah-Hartman <email@example.com>
Alan Cox <firstname.lastname@example.org>
Make sure you always send a copy to a development mailing list, do not just
kernel developers privately, as their email load is quite high. By
emailing the mailing list, you offer up the ability for anyone to help
you out with your question - taking advantage of the large development
community - and you avoid overloading the individual maintainers any more
than they are already overloaded.
What happens if I get no response from my email?
Be persistent. If you do not hear back within a week, send a friendly
"did you miss this email?" type response.
In the BSD world, there is a "security officer." Why is there no
"security officer" for the Linux kernel?"
It is true there is no one person responsible for security for the Linux
kernel, it is a group of developers who have taken this role on. The
email address email@example.com goes directly to this group
of developers who will quickly respond to any reported problems.
Instructions on how to contact this list, and the rules around which
they operate concerning disclosure and amount of time before publicly
fixing the problem, can be found in the Linux kernel file
Documentation/SecurityBugs. If anyone has any questions
about these rules, feel free to contact the security team for
Do you look at the code of the BSDs in order to find new ideas and
concepts, or do you ignore them completely?
This is a personal decision on where to find ideas to implement
in Linux. As far as I am concerned, I have not looked at the BSDs in
many many years, as I have been busy with lots of Linux-only things
(driver model, USB, Linux Driver Project, etc.) But other kernel
developers do work with the BSD developers on coming up with solutions
to different problems, or to get proper hardware support for types of
Back in the early days of USB support in Linux, I did work with a number
of the BSD USB kernel developers to share how specific devices operated
so that drivers could be written for both operating systems, and
overall, the developers are quite friendly toward each other, as we are
working toward solving the same types of problems, but usually in
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