[RFC PATCH v1 21/26] docs: reporting-bugs: details on writing and sending the report

From: Thorsten Leemhuis
Date: Thu Oct 01 2020 - 04:41:25 EST


Outline how to write the report. Give instructions that hopefully will
make people write better reports that ideally are also quick to evaluate
for kernel developers.

At the same time put some more faith into the readers to make them
provide all relevant data. That's a bit different to the old approach,
which told people to always send contents of files like /proc/ioports or
/proc/iomem, which in a lot of cases won't be needed and make reports
unnecessarily big.

That's also why this commit removes scripts/ver_linux as well: the
details it collects are only needed in some situations and make reports
bigger and harder to compile without good reason. Additionally, some
distributions do not ship it; a better, more modern script would likely
resist in tools/, then distros might start shipping it in packages like
"linux-tools".

Signed-off-by: Thorsten Leemhuis <linux@xxxxxxxxxxxxx>
---
Documentation/admin-guide/reporting-bugs.rst | 247 +++++++++++++++----
scripts/ver_linux | 81 ------
2 files changed, 198 insertions(+), 130 deletions(-)
delete mode 100755 scripts/ver_linux

diff --git a/Documentation/admin-guide/reporting-bugs.rst b/Documentation/admin-guide/reporting-bugs.rst
index 71c49347c544..b06935cad880 100644
--- a/Documentation/admin-guide/reporting-bugs.rst
+++ b/Documentation/admin-guide/reporting-bugs.rst
@@ -845,6 +845,204 @@ freshly to each newer kernel version you try. Afterwards run
enabling any new feature, as those are allowed to cause regressions.


+Write and send the report
+-------------------------
+
+ *Start to compile the report by writing a detailed description about the
+ issue. Always mentions a few things: the latest kernel version you installed
+ for reproducing, the Linux Distribution used, and your notes how to
+ reproduce the issue. Ideally, make the kernels build configuration (.config)
+ and the output from ``dmesg`` available somewhere on the net and link to it.
+ Include or upload all other information that might be relevant, like the
+ output/screenshot of an Oops or the output from ``lspci``. Once you wrote
+ this main part insert a normal length paragraph on top of it outlining the
+ issue and the impact quickly. On top of this add one sentence that briefly
+ describes the problem and gets people to read on. Now give the thing a
+ descriptive title or subject that yet again is shorter. Then you're ready to
+ send or file the report like the MAINTAINERS file told you, unless you are
+ dealing with one of those 'issues of high priority': they need special care
+ which is explained in 'Special handling for high priority issues' below.*
+
+Now that you have prepared everything it's time to write your report. How to do
+that is partly explained by the two documents linked to in the preface above.
+
+This text will only mention a few of the essentials as well as things apecific
+to the Linux kernel. There is one thing that fits both categories: the most
+crucial parts of your report are the title/subject, the first sentence and the
+first paragraph. Developers often get quite a lot of mail and have to quickly
+decide if one is really worth reading. Developer sometimes take just a few
+seconds to skim a mail before deciding if it's worth a closer look. Thus: the
+better the top section of your report, the higher are the chances that someone
+will look into it and help you. And that why you should ignore them for now
+and write the detailed report first. ;-)
+
+Things each report should mention
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Describe in detail how your issue happens with the fresh vanilla kernel you
+installed. Try to include the step-by-step instructions you wrote and optimized
+earlier that descibe how you and ideally others can reproduce the issue; in
+those rare cases where that's impossible try to describe what you did to trigger
+it.
+
+Also include all the relevant information others might need to understand the
+issue and its environment. What's actually needed depends a lot on the issue,
+but there are some things you should include always:
+
+ * the output from ``cat /proc/version``, which contains the Linux kernel
+ version number and the compiler it was built with.
+
+ * the Linux distribution the machine is running (``hostnamectl | grep
+ "Operating System"``)
+
+ * the architecture of the CPU and the operating system (``uname -mi``)
+
+ * if you are dealing with a regression and performed a bisection, mention the
+ subject and the commit-id of the culprit.
+
+In a lot of cases it's also wise to make two more things available to those
+that read your report:
+
+ * the configuration used for building your Linux kernel (the '.config' file)
+
+ * the kernels messages that you get from ``dmesg``. Make sure it near the top
+ contains a line like 'Linux version 5.8-1 (foobar@xxxxxxxxxxx) (gcc (GCC)
+ 10.2.1, GNU ld version 2.34) #1 SMP Mon Aug 3 14:54:37 UTC 2020', as
+ otherwise messages from the first boot phase are already gone from the
+ buffer. In this case instead consider using ``journalctl -b 0 -k``;
+ alternatively you can also reboot, reproduce the issue and call ``dmesg``
+ right afterwards.
+
+This data files are big, that's why it's a bad idea to put them directly into
+your report. If you are filing the issue in a bug tracker then attach them to
+the ticket. If you report the issue by mail do not attach them, as that makes
+the mail too large; instead do one of these things:
+
+ * Upload the files somewhere public (your website, a public file paste
+ service, a ticket created just for this purpose on `bugzilla.kernel.org
+ <https://bugzilla.kernel.org/>`_, ...) and include a link to them in your
+ report. Ideally use something where the files stay available for years, as
+ they could be useful to someone many years from now; this for example can
+ happen if somebody else runs into the same issue or when a developer works on
+ some code that was changed to fix your issue.
+
+ * Put the files aside and mention you will send them later in individual
+ replies to your own mail. Just remember to actually do that once the report
+ went out. ;-)
+
+Things that might be wise to provide
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Depending on the issue you might need to add more files with background data.
+Here are a few suggestions what often is good to provide:
+
+ * If you are dealing with a 'warning', an 'OOPS' or a 'panic' from the kernel,
+ include it. If you can't copy' n'paste it try to capture a netconsole trace
+ or take a picture of the screen.
+
+ * If the issue might be related to your computer hardware mention what kind of
+ system you use. If you for example have problems with your graphics card
+ mention its manufacturer and the cards model. If it's a Laptop mention its
+ name, but try to make sure it's meaningful. 'Dell XPS 13' for example is
+ not, because it might be the one from 2012; that one might look a bit similar
+ to the one sold today, but apart from that the two have nothing in common.
+ Hence, in such cases add the exact model number, which for example are
+ '9380' or '7390' for XPS 13 models introduced during 2019. Names like
+ 'Lenovo Thinkpad T590' are also somewhat ambiguous: there are variants of
+ this Laptop with and without a dedicated graphics chip, so try to find the
+ exact models name or specify the main components.
+
+ * Mention the Software in the environment that's relevant. If you have
+ problems with loading modules, you want to mention the versions of kmod,
+ systemd, and udev in use. If one of the DRM drivers misbehaves, you want to
+ state the versions of libdrm and Mesa; also specify your Wayland compositor
+ or the X-Server and its driver. If you have a filesystem issue, mention the
+ version of corresponding filesystem utilities (e2fsprogs, btrfs-progs,
+ xfsprogs, …).
+
+ * Gather additional information from the kernel that might be of interest. The
+ output from ``lspci -nn`` will for example help others to identify what
+ hardware you use. If you have a problem with hardware you even might want to
+ make the output from ``sudo lspci -vvv`` available, as that provides
+ insights how the components were configured. For some issues it might be
+ good to include the contents of files like ``/proc/cpuinfo``,
+ ``/proc/ioports``, ``/proc/iomem``, ``/proc/modules``, or
+ ``/proc/scsi/scsi``. Some subsystem also offer tools to collect relevant
+ information. One such tool is ``alsa-info.sh`` `which the audio/sound
+ subsystem developers provide <https://www.alsa-project.org/wiki/AlsaInfo>`_.
+
+That will give your some ideas what data might be wise to send, but you have to
+think yourself what might be helpful for others to know. Don't worry too much
+about forgetting something: developers will ask for additional details they
+need; but making everything important available from the start increases the
+chance someone will take a closer look.
+
+The important part: the head of your report
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Now that you have the detailed part of the report prepared let's get back to
+the most important section: the first few sentences. Thus go to the top, add
+something like 'The detailed description:' before the part you wrote and insert
+two newlines at the top. Now write one normal length paragraph that describes
+the issue roughly. Leave out all boring details and focus on the crucial parts
+readers need to know to understand what this is all about; if you think this
+bug affects a lot of users, mention this to get people interested.
+
+Once you did that insert two more lines at the top and write a one sentence
+summary that explains quickly what the report is about. After that you have to
+get even more abstract and write an even short subject/title for the report.
+
+Now that you have written this part take some time to optimize it, as it is the
+most important parts of your report: a lot of people will only read this before
+they decide if reading the rest is time well spend.
+
+Now send or file the report like the `MAINTAINERS file
+<https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/plain/MAINTAINERS>`_
+told you, unless it's one of those 'issues of high priority' outlined earlier:
+In that read the next subsection before sending the report.
+
+Special handling for high priority issues
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+High priority issues need special handling when sending the report:
+
+
+ * *Regression* If the issue is a regression add [REGRESSION] to the mails
+ subject or the title in the bug-tracker. If you did not perform a bisection
+ mention at least the latest mainline version you tested that worked fine (say
+ 5.7) and the oldest where the issue occurs (say 5.8). If you did a successful
+ bisection mention the commit id and subject of the change that causes the
+ regression. Also make sure to add the author of that change to your report;
+ if you need to file your bug in a bug-tracker forward the report to him in a
+ private mail and mention where your filed it.
+
+ * *Severe bug*: make sure the subject or ticket title as well as the first para
+ makes the severeness obvious.
+
+ * *Security issues*: for these issues your will have to evaluate if a
+ short-term risk to other users would arise if details were publicly
+ disclosed. If that's not the case simply proceed with reporting the issue as
+ described. For issues that bear such a risk you will need to adjust the
+ reporting process slightly:
+
+ * If the MAINTAINERS file instructed you to report the issue by mail, do not
+ CC any public mailing lists.
+
+ * If you were supposed to file the issue in a bug tracker make sure to mark
+ the ticket as 'private' or 'security issue'. If the bug tracker does not
+ offer a way to keep reports private, forget about it and send your report
+ as a private mail to the maintainers instead.
+
+ In both cases make sure to inform those that the MAINTAINERS file lists in
+ the section 'security contact'. Ideally CCing them on the mail with the
+ report. If you filed it in a bug tracker forward the reports text, but on top
+ of it put a small note where you mention that you filed it with a link to the
+ ticket.
+
+ See :ref:`Documentation/admin-guide/security-bugs.rst <securitybugs>` for more
+ information.
+
+
.. ############################################################################
.. Temporary marker added while this document is rewritten. Sections above
.. are new and dual-licensed under GPLv2+ and CC-BY 4.0, those below are old.
@@ -867,55 +1065,6 @@ How to report Linux kernel bugs
===============================


-Gather information
-------------------
-
-The most important information in a bug report is how to reproduce the
-bug. This includes system information, and (most importantly)
-step-by-step instructions for how a user can trigger the bug.
-
-If the failure includes an "OOPS:", take a picture of the screen, capture
-a netconsole trace, or type the message from your screen into the bug
-report.
-
-This is a suggested format for a bug report sent via email or bugzilla.
-Having a standardized bug report form makes it easier for you not to
-overlook things, and easier for the developers to find the pieces of
-information they're really interested in. If some information is not
-relevant to your bug, feel free to exclude it.
-
-First run the ver_linux script included as scripts/ver_linux, which
-reports the version of some important subsystems. Run this script with
-the command ``awk -f scripts/ver_linux``.
-
-Use that information to fill in all fields of the bug report form, and
-post it to the mailing list with a subject of "PROBLEM: <one line
-summary from [1.]>" for easy identification by the developers::
-
- [1.] One line summary of the problem:
- [2.] Full description of the problem/report:
- [3.] Keywords (i.e., modules, networking, kernel):
- [4.] Kernel information
- [4.1.] Kernel version (from /proc/version):
- [4.2.] Kernel .config file:
- [5.] Most recent kernel version which did not have the bug:
- [6.] Output of Oops.. message (if applicable) with symbolic information
- resolved (see Documentation/admin-guide/bug-hunting.rst)
- [7.] A small shell script or example program which triggers the
- problem (if possible)
- [8.] Environment
- [8.1.] Software (add the output of the ver_linux script here)
- [8.2.] Processor information (from /proc/cpuinfo):
- [8.3.] Module information (from /proc/modules):
- [8.4.] Loaded driver and hardware information (/proc/ioports, /proc/iomem)
- [8.5.] PCI information ('lspci -vvv' as root)
- [8.6.] SCSI information (from /proc/scsi/scsi)
- [8.7.] Other information that might be relevant to the problem
- (please look in /proc and include all information that you
- think to be relevant):
- [X.] Other notes, patches, fixes, workarounds:
-
-
Follow up
=========

diff --git a/scripts/ver_linux b/scripts/ver_linux
deleted file mode 100755
index 0968a3070eff..000000000000
--- a/scripts/ver_linux
+++ /dev/null
@@ -1,81 +0,0 @@
-#!/usr/bin/awk -f
-# SPDX-License-Identifier: GPL-2.0
-# Before running this script please ensure that your PATH is
-# typical as you use for compilation/installation. I use
-# /bin /sbin /usr/bin /usr/sbin /usr/local/bin, but it may
-# differ on your system.
-
-BEGIN {
- usage = "If some fields are empty or look unusual you may have an old version.\n"
- usage = usage "Compare to the current minimal requirements in Documentation/Changes.\n"
- print usage
-
- system("uname -a")
- printf("\n")
-
- vernum = "[0-9]+([.]?[0-9]+)+"
- libc = "libc[.]so[.][0-9]+$"
- libcpp = "(libg|stdc)[+]+[.]so[.][0-9]+$"
-
- printversion("GNU C", version("gcc -dumpversion"))
- printversion("GNU Make", version("make --version"))
- printversion("Binutils", version("ld -v"))
- printversion("Util-linux", version("mount --version"))
- printversion("Mount", version("mount --version"))
- printversion("Module-init-tools", version("depmod -V"))
- printversion("E2fsprogs", version("tune2fs"))
- printversion("Jfsutils", version("fsck.jfs -V"))
- printversion("Reiserfsprogs", version("reiserfsck -V"))
- printversion("Reiser4fsprogs", version("fsck.reiser4 -V"))
- printversion("Xfsprogs", version("xfs_db -V"))
- printversion("Pcmciautils", version("pccardctl -V"))
- printversion("Pcmcia-cs", version("cardmgr -V"))
- printversion("Quota-tools", version("quota -V"))
- printversion("PPP", version("pppd --version"))
- printversion("Isdn4k-utils", version("isdnctrl"))
- printversion("Nfs-utils", version("showmount --version"))
- printversion("Bison", version("bison --version"))
- printversion("Flex", version("flex --version"))
-
- while ("ldconfig -p 2>/dev/null" | getline > 0) {
- if ($NF ~ libc && !seen[ver = version("readlink " $NF)]++)
- printversion("Linux C Library", ver)
- else if ($NF ~ libcpp && !seen[ver = version("readlink " $NF)]++)
- printversion("Linux C++ Library", ver)
- }
-
- printversion("Dynamic linker (ldd)", version("ldd --version"))
- printversion("Procps", version("ps --version"))
- printversion("Net-tools", version("ifconfig --version"))
- printversion("Kbd", version("loadkeys -V"))
- printversion("Console-tools", version("loadkeys -V"))
- printversion("Oprofile", version("oprofiled --version"))
- printversion("Sh-utils", version("expr --v"))
- printversion("Udev", version("udevadm --version"))
- printversion("Wireless-tools", version("iwconfig --version"))
-
- while ("sort /proc/modules" | getline > 0) {
- mods = mods sep $1
- sep = " "
- }
- printversion("Modules Loaded", mods)
-}
-
-function version(cmd, ver) {
- cmd = cmd " 2>&1"
- while (cmd | getline > 0) {
- if (match($0, vernum)) {
- ver = substr($0, RSTART, RLENGTH)
- break
- }
- }
- close(cmd)
- return ver
-}
-
-function printversion(name, value, ofmt) {
- if (value != "") {
- ofmt = "%-20s\t%s\n"
- printf(ofmt, name, value)
- }
-}
--
2.26.2