[Bug 1059827] Re: Non trivial grub2 installs no longer fit in small embed areas

[D3m0n1q_733rz]

Actually, Phillip, BtrFS requires 2MB for a Grub2 installation.  So, while you are correct that it does start at 1MB, the partitioner does have an error in not including that the rules for BtrFS are different.  The normal 1MB is a part of the normal MBR rules.  Since Grub2 requires some extra installation space for the BtrFS partition information, GParted should warn when BtrFS is used and a partition is started less than 2MB from the beginning of the drive.  For everything else, 1MB works fine.
So, this would be a problem with the partitioner not realizing the rules are different and the installer not seeing that the partitioner made a mistake and that Grub2 can not be properly installed inside of the 1MB space for a BtrFS partition.

Ext4 and other partitions that are not BtrFS have no problem with the
1MB start point.

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https://bugs.launchpad.net/bugs/1059827

Title:
  Non trivial grub2 installs no longer fit in small embed areas

Status in “grub2” package in Ubuntu:
  Triaged

Bug description:
  Traditionally the first boot track of the disk was left unpartitioned.
  This area is used to embed the grub2 core.img file.  The size of this
  area used to typically be 62 sectors.  In recent years the typical
  size has changed to 2048 sectors to keep the partitions aligned to a 1
  MiB boundary for performance reasons on SSDs and newer hard disks with
  4KiB sector sizes.  All but the most trivial configurations of grub no
  longer fit in the old 62 sector size embed area.  This results in grub
  complaining that your embed area is unusually small.

  Upstream appears to have no desire to support such configurations, so
  this is unlikely to be fixed, but I will leave this bug report open
  for now.  The workaround for the problem is to repartition the disk
  with modern partitioning tools that will align partitions to 1MiB,
  thus leaving 2048 sectors for the embed area.

  Another workaround is to setup a simple ext4 /boot partition rather
  than try to boot directly from raid or lvm or btrfs.

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