[PATCH v3] docs: admin-guide: Clarify sentences
From: Cristian Souza
Date: Fri Apr 10 2020 - 16:04:14 EST
Changes to make the text more formal and organized. The reasons are now cited and described at the same time.
Minor grammatical problems have also been fixed.
Signed-off-by: Cristian Souza <cristianmsbr@xxxxxxxxx>
---
Changes in v2:
- Text more formal and organized
Changes in v3:
- Authors at the top of the file
- Removal of the source file in which the message is located
- All lines under 80 characters
Documentation/admin-guide/init.rst | 57 +++++++++++++++---------------
1 file changed, 28 insertions(+), 29 deletions(-)
diff --git a/Documentation/admin-guide/init.rst b/Documentation/admin-guide/init.rst
index 0c2c9138f268..41f06a09152e 100644
--- a/Documentation/admin-guide/init.rst
+++ b/Documentation/admin-guide/init.rst
@@ -1,38 +1,39 @@
Explaining the "No working init found." boot hang message
=========================================================
-
-Message location: ``init/main.c``
+:Authors: Andreas Mohr <andi at lisas period de>
+ Cristian Souza <cristianmsbr at gmail period com>
This document provides some high-level reasons for failure
(listed roughly in order of execution) to load the init binary.
-1) **Unable to mount root FS**: Set "debug" kernel parameter (in bootloader config file or CONFIG_CMDLINE)
- to get more detailed kernel messages.
+1) **Unable to mount root FS**: Set "debug" kernel parameter (in bootloader
+ config file or CONFIG_CMDLINE) to get more detailed kernel messages.
-2) **init binary doesn't exist on rootfs**: Make sure you have the correct root FS type
- (and ``root=`` kernel parameter points to the correct partition),
- required drivers such as storage hardware (such as SCSI or USB!)
- and filesystem (ext3, jffs2, etc.) are builtin (alternatively as modules,
- to be pre-loaded by an initrd).
+2) **init binary doesn't exist on rootfs**: Make sure you have the correct
+ root FS type (and ``root=`` kernel parameter points to the correct
+ partition), required drivers such as storage hardware (such as SCSI or
+ USB!) and filesystem (ext3, jffs2, etc.) are builtin (alternatively as
+ modules, to be pre-loaded by an initrd).
-3) **Broken console device**: Possibly a conflict in ``console= setup`` --> initial console unavailable.
- E.g. some serial consoles are unreliable due to serial IRQ issues (e.g.
- missing interrupt-based configuration).
+3) **Broken console device**: Possibly a conflict in ``console= setup``
+ --> initial console unavailable. E.g. some serial consoles are unreliable
+ due to serial IRQ issues (e.g. missing interrupt-based configuration).
Try using a different ``console= device`` or e.g. ``netconsole=``.
-4) **Binary exists but dependencies not available**: E.g. required library dependencies of the init binary such as
- ``/lib/ld-linux.so.2`` missing or broken. Use
- ``readelf -d <INIT>|grep NEEDED`` to find out which libraries are required.
-
-5) **Binary cannot be loaded**: Make sure the binary's architecture matches your hardware.
- E.g. i386 vs. x86_64 mismatch, or trying to load x86 on ARM hardware.
- In case you tried loading a non-binary file here (shell script?),
- you should make sure that the script specifies an interpreter in its shebang
- header line (``#!/...``) that is fully working (including its library
- dependencies). And before tackling scripts, better first test a simple
- non-script binary such as ``/bin/sh`` and confirm its successful execution.
- To find out more, add code ``to init/main.c`` to display kernel_execve()s
- return values.
+4) **Binary exists but dependencies not available**: E.g. required library
+ dependencies of the init binary such as ``/lib/ld-linux.so.2`` missing or
+ broken. Use ``readelf -d <INIT>|grep NEEDED`` to find out which libraries
+ are required.
+
+5) **Binary cannot be loaded**: Make sure the binary's architecture matches
+ your hardware. E.g. i386 vs. x86_64 mismatch, or trying to load x86 on ARM
+ hardware. In case you tried loading a non-binary file here (shell script?),
+ you should make sure that the script specifies an interpreter in its
+ shebang header line (``#!/...``) that is fully working (including its
+ library dependencies). And before tackling scripts, better first test a
+ simple non-script binary such as ``/bin/sh`` and confirm its successful
+ execution. To find out more, add code ``to init/main.c`` to display
+ kernel_execve()s return values.
Please extend this explanation whenever you find new failure causes
(after all loading the init binary is a CRITICAL and hard transition step
@@ -42,8 +43,6 @@ Further TODOs:
- Implement the various ``run_init_process()`` invocations via a struct array
which can then store the ``kernel_execve()`` result value and on failure
log it all by iterating over **all** results (very important usability fix).
-- Try to make the implementation itself more helpful in general,
- e.g. by providing additional error messages at affected places.
+- Try to make the implementation itself more helpful in general, e.g. by
+ providing additional error messages at affected places.
-Andreas Mohr <andi at lisas period de>
-Cristian Souza <cristianmsbr at gmail period com>
--
2.25.1