Although the EFI specification enforces support for FAT ESP, it's free for EFI implementations to implement support for ESPs with other formats (e.g. ext4, ntfs, etc), and at least U-Boot EFI will support ext4 ESP if U-Boot is built with ext4 support. In some situations a GRUB installation on such a non-FAT ESP could be useful (e.g. a NTFS-based USB disk that can dual boot a Windows installation media and a Linux LiveCD).
As this is advanced and implementation-dependent behavior, let grub-install allow this kind of installation, but only when --force is specified. Signed-off-by: Icenowy Zheng <u...@icenowy.me> --- util/grub-install.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/util/grub-install.c b/util/grub-install.c index d601c3e8d..1f5d58b2b 100644 --- a/util/grub-install.c +++ b/util/grub-install.c @@ -1092,7 +1092,15 @@ main (int argc, char *argv[]) efidir_is_mac = 1; if (!efidir_is_mac && grub_strcmp (fs->name, "fat") != 0) - grub_util_error (_("%s doesn't look like an EFI partition"), efidir); + { + if (force) + grub_util_warn (_ + ("%s doesn't look like an EFI partition, system may not boot"), + efidir); + else + grub_util_error (_("%s doesn't look like an EFI partition"), + efidir); + } /* The EFI specification requires that an EFI System Partition must contain an "EFI" subdirectory, and that OS loaders are stored in -- 2.35.1 _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel