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authorAndi Shyti <andi.shyti@linux.intel.com>2026-08-22 14:19:12 +0200
committerAndi Shyti <andi.shyti@linux.intel.com>2026-08-22 14:19:34 +0200
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Merge tag 'rust-i2c-for-7.3' into i2c/i2cgrafted
i2c: rust: mark I2cAdapter methods as inline A single cleanup for the Rust I2C abstractions, targeting 7.3. `I2cAdapter::get`, `inc_ref`, and `dec_ref` are trivial wrappers around `i2c_get_adapter`/`i2c_put_adapter` and were showing up as their own symbols in the build. Mark them `#[inline]` so they get folded into their callers instead. Signed-off-by: Igor Korotin <igor.korotin@linux.dev> * tag 'rust-i2c-for-7.3': i2c: rust: mark I2cAdapter methods as inline
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+Explaining the "No working init found." boot hang message
+=========================================================
+: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.
+
+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).
+ 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.
+
+Please extend this explanation whenever you find new failure causes
+(after all loading the init binary is a CRITICAL and hard transition step
+which needs to be made as painless as possible), then submit a patch to LKML.
+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.
+