Originally written: 3/14/2012; last Web page update:
-12/15/2013, referencing rEFInd 0.7.6
+12/12/2015, referencing rEFInd 0.10.1
-
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+
This Web page is provided free of charge and with no annoying outside ads; however, I did take time to prepare it, and Web hosting does cost money. If you find this Web page useful, please consider making a small donation to help keep this site up and running. Thanks!
As described in reference to version 0.9.2 on the Revisions page, rEFInd includes a
+ delicate and hackish workaround to a problem introduced by Shim
+ 0.8. Developing a better solution to that problem is a high
+ priority.
+
The support for booting legacy (BIOS) OSes on UEFI-based PCs
currently has a number of limitations. Most importantly, it works
off of the list of boot devices stored in the computer's NVRAM. I'd
@@ -171,16 +173,21 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
optical drives and uses generic icons rather than OS-specific
icons.
-
Currently, rEFInd can detect whether it's compiled for x86
- or x86-64 systems and displays this information in its
- "About" screen (AboutrEFInd() in main.c). I'd
- like to add detection for Itanium and ARM systems, but I have no
- way to test such changes.
+
rEFInd's Makefiles and, to a lesser extent, C code,
+ support x86, x86-64, and ARM64 CPUs. EFI is also
+ available for Itanium (IA-64) and ARM32 CPUs, so I'd like to add
+ this support.
+
+
Currently, rEFInd can detect whether it's compiled for x86,
+ x86-64, or ARM64 systems and displays this information in
+ its "About" screen (AboutrEFInd() in main.c). I'd
+ like to add detection for Itanium and 32-bit ARM systems, but I
+ have no way to test such changes.
-
Although the ICNS file format used by rEFInd supports multiple
- image sizes, if a size that rEFInd needs isn't present in the file,
- rEFInd can't use the icon. The ability to scale images to the
- desired size would be useful.
+
Further to the preceding, rEFInd's GPT-scanning code (used to
+ extract partition names) includes assumptions about byte order, and
+ so will work only on little-endian CPUs such as the x86 and
+ x86-64.
A way to set the color of the font would be useful for theming
purposes.
@@ -190,20 +197,8 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
characters, and by enabling use of variable-width as well as
monospace fonts.
-
I would like to be able to specify the volume on which a boot
- loader resides using a partition GUID value, but extracting a GUID
- from the partition data is harder than extracting the volume's
- label or counting up the filesystem numbers.
-
-
Currently, if a filesystem's label comes up empty, rEFInd
- substitutes the size, so you get displays like boot
- EFI\foo\bar.efi from 90 GiB volume. I'd like to add more
- checks to substitute the GPT partition label if the
- filesystem label comes up empty.
-
-
Along the lines of the previous item, the
- default_selection might be expanded to support some form
- of specification of disk types, as in a special entry for any
+
The default_selection might be expanded to support some
+ form of specification of disk types, as in a special entry for any
optical disk or any external disk, no matter what its name is.
It would be useful to be able to specify paths to boot loaders
@@ -215,7 +210,21 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
upper-left corner of the screen. Having an option to support a
transparent background is desirable to some users.
-
+
When delivering rEFInd as a boot loader from a network server,
+ rEFInd is limited to its default options and can boot only local
+ OSes, not network OSes. The cause is that the server delivers a
+ single file, so rEFInd is divorced from its configuration and
+ support files.
+
+
A way to identify specific Windows versions and present unique
+ icons or change the text is desirable. Currently, a crude
+ distinction of XP and earlier vs. Vista and later is possible for
+ BIOS-booting on Macs, but no such distinction is made for EFI-mode
+ booting, and nothing finer-grained is attempted. Improvements will
+ probably require identifying unique features of each version's boot
+ loader files or boot sector code.
+
+
Known bugs that need squashing:
@@ -229,8 +238,7 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
removing rEFInd's drivers has caused the problem to go into
remission.
Some EFIs have bugs that cause the allegedly case-insensitive
StriCmp() function to perform a case-sensitive comparison.
This causes any number of bugs in file matching. For instance:
Changing the case of icon filename extensions (or various other
@@ -238,14 +246,10 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
"generic" ones; and rEFInd sometimes appears in its own menu (the
firmware sometimes returns an all-caps version of the filename, but
other times returns the filename with the correct case, causing a
- mismatch if the path includes lowercase elements). Some of these
- problems can be overcome by converting both strings to be compared
- to one case before doing the comparison, but others aren't so easy,
- since I think StriCmp() is being called internally to the
- EFI. In any event, it'd be nice to fix some of these problems.
- OTOH, this is a workaround for a bug on just one EFI
- implementation, and a dismal one at that, so I'm inclined to just
- let it go.
+ mismatch if the path includes lowercase elements). This problem is
+ worse when compiling rEFInd with GNU-EFI than with Tianocore.
+ Version 0.9.1 has made improvements on this score, but some issues
+ may continue to lurk.
The Shutdown option works correctly on Macs, but not on many UEFI-based
PCs. On such systems, Shutdown reboots the computer. This should be
@@ -266,6 +270,13 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
have the equipment and skill to do so, I'd be interested in
receiving a patch.
+
If you use a true MBR disk on a Mac to boot Windows or some other
+ BIOS-only OS, and if that disk has an extended partition, bogus
+ additional BIOS/legacy-bootable options may appear in the rEFInd
+ menu. The reason appears to be a bug in the handling of
+ extended/logical partitions in the refind/lib.c file, but
+ I haven't fully tracked it down.
+
The re-scan feature occasionally produces odd results, such as
ignoring new media or keeping old media that have been ejected.
This should be investigated and fixed.
The code is in need of review to search for memory leaks and
similar problems.
-
If the user has a Linux software RAID 1 array, rEFInd will detect
- kernels or boot loaders in RAID 1 twice. This could be fixed by
- adding a check for duplicate filesystem UUIDs to the
- partition-scanning code.
+
If the user has a Linux software RAID 1 array with Btrfs, HFS+,
+ or FAT filesystem, rEFInd will detect kernels or boot loaders in
+ RAID 1 twice. Checks to prevent this with ext2/3/4fs and ReiserFS
+ already exist; these checks could be expanded to block such
+ duplication with more filesystems.
Some Macs experience problems with waking up from suspend states
when rEFInd is installed. Unfortunately, I lack the hardware to
@@ -304,7 +316,13 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
pmset to disable the autopoweroff option is
claimed
- by some to at least partially fix the problem, though.
+ by some to at least partially fix the problem, though. Using
+ the --ownhfs installation option may also help in some
+ cases.
+
+
If you activate BIOS-mode support on UEFI-based PCs, you may find
+ multiple copies of the BIOS-mode loaders added to your firmware's
+ boot manager. Only one copy shows up in rEFInd, though.
EFI supports network boots. rEFInd doesn't, but it would be nice if
- it would.
-
There's currently no way to create a manual boot stanza for a
BIOS-booted OS. This isn't a big priority for me personally, but I
can see how it could be for some people.
-
I've received queries about rEFInd's ability to work with Apple's
- whole-disk encryption scheme that's new with OS X 10.7.
- Unfortunately, I lack the hardware to test this, but my
- understanding is that it will work correctly if rEFInd is
- installed in the ESP rather than on the Mac OS X root partition.
- See this
- forum thread for more information.
-
I'd like to find a way to enable users to enter customizations for
boot options and then save them to the refind.conf file.
One possible way to implement this would be to have manual boot
stanzas override auto-detected boot loader definitions for the same
boot loader file.
+
Along similar lines, some users have asked for a way to take
+ detected boot programs and create a set of manual boot stanzas for
+ them, so that they can be modified manually.
+
+
Support for touchscreens and/or configurable buttons for rEFInd's
+ actions would enable use of rEFInd on tablet computers that lack
+ complete keyboards.
+
+
The ability to rotate the display for users who rotate their
+ monitors or who use tablets would be helpful.
+
+
GRUB provides a configuration-file command called outb
+ that enables manipulating hardware registers. Something similar,
+ via the mm command, can be done in the EFI shell. I'd like
+ to add such a feature to rEFInd, since it enables doing things like
+ disabling one or another video output on Macs with two video
+ cards.
+
I have thoughts about creating an EFI configuration tool and
information utility—something to tell you about your hard
disks, enable you to manage MOKs, adjust boot loader priority in
@@ -351,13 +375,15 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
loader settings—say, to disable one specific boot loader or
change its icon.
-
The ability to rotate the display for users who rotate their
- monitors would be helpful.
+
A GUI configuration tool for host OSes (Linux, OS X, Windows, etc.)
+ would be nice, but it's low on my personal priority list. If you'd
+ like to contribute, I prefer something written in a cross-platform
+ GUI toolkit, so that a single code base can be used on any of the
+ major OSes.
-
A GUI configuration tool would be nice, but it's low on my personal
- priority list. If you'd like to contribute, I prefer something
- written in a cross-platform GUI toolkit, so that a single code base
- can be used on any of the major OSes.
+
The ability to produce audio output (at least a simple "beep") to signal
+ to visually impaired users when rEFInd is ready to accept input would be
+ helpful.
@@ -372,9 +398,6 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
Linux's EFI stub loader). Also along these lines, adding drivers
for Linux LVM and RAID setups would be useful.
-
The HFS+ driver returns a volume label of "HFS+ volume", no matter
- what the volume's real label is.
-
This may not be possible, or it may require a new driver, but a way
to have the drivers access files (like a Linux loopback mount) is
desirable.
Improvements to gptsync, refind-install, or other
support tools:
@@ -398,13 +421,10 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
under some circumstances, such as when it makes no changes to the
partition table. Fix this.
-
When updating a system with Secure Boot via an RPM or Debian
- package, the RPM installation script can detect rEFInd's existing
- shim or PreLoader program and pass options to install.sh
- to try to copy these programs over themselves. This results in a
- message that the copy was over the same file and an error message
- that there were problems with the installation, although this isn't
- really the case.
+
rEFInd's support for network booting is primitive and relies on the
+ external iPXE package. In my own testing, iPXE retrieves the
+ BIOS-mode boot loader from some servers that offer both, which
+ makes it useless on those networks.
+
@@ -56,8 +57,7 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
-
-