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Subject: Re: [PATCH] vmlinux.lds.h: Force-align ELF notes section to four bytes
Date:   Thu, 27 Apr 2023 05:14:10 +0000
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PS: As additional information for posterity, there are various conditions that
explain why this is/was only a problem on some specific distributions:

* In addition to dwarves/pahole 1.24, binutils 2.40 seems to also be required
  for the problem to occur (in Arch, downgrading to binutils 2.39 fixes it).
* Debian (and thus derived distributions) configures binutils with
  `--disable-x86-used-note`, which by default disables emitting the GNU notes
  which ultimately cause the .notes section to be aligned to 8 bytes.

  On Debian Bookworm & Ubuntu 23.04, the problem reproduces when building like:
  ```
  export KCFLAGS="-Xassembler -mx86-used-note=yes"
  export KAFLAGS="-Xassembler -mx86-used-note=yes"
  make
  ```

Finally, here's a smaller .config to reproduce the problem on affected systems:
https://zealcharm.com/20230416-btf-dedup-bug-sample-configs/minimal-repro