Hi, as it turns out, syslinux in stretch is in a quite sorry state. To summarize:
1. Booting from ext4 partitions created with Debian stretch does not work, because ext4's 64bit feature is enabled by default (since Debian stretch) and not supported by syslinux [1]. 2. Booting from btrfs does not work [2]. 3. A bug in the isolinux isohybrid MBR causing boot failures with some old BIOS [3]. 4. Booting from xfs does not work (which was already the case in jessie, so not a regression in stretch) [4]. You will notice that this does not really leave any modern Unix filesystem for syslinux/extlinux to boot from… from the above problems, 1-3 are a regression compared to Debian jessie. [1] https://bugs.debian.org/833057 [2] https://bugs.debian.org/865462 [3] I didn't think to open a separate bug against syslinux, which would have been the right thing to do… the bug against debian-cd, which is affected by this problem, holds relevant information: https://bugs.debian.org/857597 [4] https://bugs.debian.org/803938 Problems 1 and 2 have an upstream fix each [5, 6] which is pretty small in size. I'm able to locally reproduce each of the two problems and also confirm that the respective patches fix the problems. Problem 3 also has a small and self-contained upstream fix. And although I have no way to test this myself, the built isohdpfx.bin file (with the fix applied) is identical to a known-good and tested version. Problem 4 is fixed upstream as well (which I have not tested yet), but the number of changes for that is pretty high. Since this is both a large patch and a not a regression from jessie, I don't intend to fix this in Debian stretch. [5] http://git.zytor.com/syslinux/syslinux.git/commit/?id=af7e95c32cea40c1e443ae301e64b27f068b4915 [6] http://git.zytor.com/syslinux/syslinux.git/commit/?id=548386049cd41e887079cdb904d3954365eb28f3 The current version in unstable contains the patches for 2 and 3 already and I've just requested sponsorship for another update which also fixes 1. Provided we do not find any regressions related to the fixes for problems 1-3, I would like to push those patches [7, 8, 9] to the version in Debian stretch in the next point release. I know the next point release is still ~6 weeks off, but bootloader changes are obviously critical. So I wanted to raise this issue well before the deadline to get an idea how (or if) I should proceed: * Is this a reasonable request, or are these changes too dangerous for a point release anyways? * What kind of testing is required / expected so these changes can be considered? Thanks Lukas [7] https://anonscm.debian.org/git/debian-cd/syslinux.git/tree/debian/patches/0016-btrfs-fix.patch?id=c61f3d0ef77ca726a0ff242c6ca6f1db90a8b9c6 [8] https://anonscm.debian.org/git/debian-cd/syslinux.git/tree/debian/patches/0017-isohdpfx.S-correct-heads-sectors.patch?id=c61f3d0ef77ca726a0ff242c6ca6f1db90a8b9c6 [9] https://anonscm.debian.org/git/debian-cd/syslinux.git/tree/debian/patches/0018-ext4-Fix-64bit-feature.patch?id=c61f3d0ef77ca726a0ff242c6ca6f1db90a8b9c6
