Hi Andy,
Responding to Mauro's cover-letter of v4 at:
https://lore.kernel.org/cover.1745453655.git.mchehab+huawei@xxxxxxxxxx/
, which did not CC'd to you.
On Thu, 24 Apr 2025 08:16:20 +0800, Mauro Carvalho Chehab wrote:
> As reported by Andy, the Kernel build system runs kernel-doc script for DRM,
> when W=1. Due to Python's normal behavior, its JIT compiler will create
> a bytecode and store it under scripts/lib/*/__pycache__. As one may be using
> O= and even having the sources on a read-only mount point, disable its
> creation during build time.
>
> This is done by adding PYTHONDONTWRITEBYTECODE=1 on every place
> where the script is called within Kbuild and when called via another script.
>
> This only solves half of the issue though, as one may be manually running
> the script by hand, without asking Python to not store any bytecode.
> This should be OK, but afterwards, git status will list the __pycache__ as
> not committed. To prevent that, add *.pyc to .gitignore.
>
> This series contain 4 patches:
>
> - patch 1 adjusts a variable that pass extra data to scripts/kerneldoc.py;
> - patch 2moves scripts/kernel-doc location to the main makefile
> and exports it, as scripts/Makefile.build will need it;
> - patch 3 disables __pycache__ generation and ensure that the entire Kbuild
> will use KERNELDOC var for the location of kernel-doc;
> - patch 4 adds *.pyc at the list of object files to be ignored.
I see Jon has merged them all, but responding here anyway.
In https://lore.kernel.org/Z_zYXAJcTD-c3xTe@xxxxxxxxxxxxxxxxxx/, you said:
> This started well, until it becomes a scripts/lib/kdoc.
> So, it makes the `make O=...` builds dirty *). Please make sure this doesn't leave
> "disgusting turd" )as said by Linus) in the clean tree.
>
>*) it creates that __pycache__ disaster. And no, .gitignore IS NOT a solution.w
Andy, I don't agree with your words "__pycache__ disaster" and
".gitignore IS NOT a solution".
Running "find . -name ".gitignore" -exec grep -nH --null -F -e ".pyc" \{\} +"
under today's Linus master returns this:
-------------------------------------------------------------
./scripts/gdb/linux/.gitignore:2:*.pyc
./drivers/comedi/drivers/ni_routing/tools/.gitignore:3:*.pyc
./tools/perf/.gitignore:32:*.pyc
./tools/testing/selftests/tc-testing/.gitignore:3:*.pyc
./Documentation/.gitignore:3:*.pyc
-------------------------------------------------------------
, and they have been working perfectly.
Having seen your response at https://lore.kernel.org/aAoERIArkvj497ns@xxxxxxxxxxxxxxxxxx/ :
> I tried before, but I admit, that I have missed something. It was a mess
> in that case. Now I probably can't repeat as I don't remember what was
> the environment and settings I had that time. I'm really glad to see it
> is working this way!
, I'm guessing you had a traumatic experience caused by python's bytecode
caching in the past. Do you still believe ".gitignore IS NOT a solution"?
