Today in gripes that about 5 people including me will have: it's really difficult to find a unified way to get a tarball from something on kernel.org to the Fedora dist-git in a way that meets the Fedora packaging guidelines.
Let's start with my pettiest gripe: the lack of a trailing 0 on official releases. Official kernel releases are usually versioned like 5.1, 5.2. Note the lack of a trailing 0 there. Stable updates are 5.2.3, 5.2.3 etc. This would be okay except for if you look at the Makefile for stable releases, there's still a 0 in the SUBLEVEL filed where stable updates come from. "But Laura, there's macros to take care of that" yes, in the kernel itself. I'm working on going from the kernel to dist-git so this means I'm writing scripts which have to re-do this work and think about this when generating a version string. If I wanted to be really petty, I'd start a conversation about changing the kernel versioning completely. The 5.0 numbering means nothing. The bump from 4.x to 5.x was because the second number was getting to high. The numbers mean nothing at this point except they keep getting larger. I'd love to see the numbers correspond to a date since the kernel is basically on a time base release at this point anyway.
Fedora has packaging guidelines describing how packages should work. It's to the benefit of everyone to follow these guidelines. The guidelines for Source recommend using tarballs and give a few other suggestions for how to set Source0 appropriately.
The Fedora kernel generates 3 types of kernel releases: official releases (v5.2, v5.2.1), rc releases (v5.3-rc6), and snapshots that don't correspond to an official tag. Currently, the way we generate all these is starting with the base (e.g. 5.2) and then applying a patch on top of it (patch-5.3-rc6, patch-5.2.10). We do this by grabbing the individual tarballs and patches from kernel.org.
I've been looking at switching Fedora to a src-git for a number of reasons (I gave a talk at Flock, the video doesn't seem to be up yet). The idea would be to use the src-git tree primarily and only use the dist-git for generating the rpm. Because of this, I was looking at switching to single tarballs instead of the patching model because that matches what the src-git tree looks like: an upstream tarball plus a bunch of patches. It turns out this is a pain.
If you look at kernel.org, the -rc tarballs are generated only from Linus' git tree and not synced to the cdn. That make sense given -rc tarballs are really only interesting for a week at a time. Except that means we technically need a different Source0 for -rc and not -rc releases. Okay, Fedora offers an option to generate an archive from a git url, so we could just use the git tree. Except stable updates don't come from Linus' tree they come from the stable tree. This means we would end up needing a different Source0 depending on whether or not we're getting a tarball from a stable tree vs. a base release.
The Fedora guidelines do have a clause for stating you don't have to give a URL for some circumstances and that could be an option. But the point of giving a URL is to help with auditing of the package. Maybe you don't trust these names who push broken updates and can't even spell 'kernel' half the time so you want to see where the source comes from. This is an important part of open source and I do think transparency of where tarballs come from is important.
None of this is a complaint for the kernel.org administrators either. The kernel.org team does a wonderful job of supporting a variety of needs. This is just a set of particularly narrow complaints.