Originally written: 3/14/2012; last Web page update:
-5/20/2012, referencing rEFInd 0.4.0
+12/12/2015, referencing rEFInd 0.10.1
-
I'm a technical writer and consultant specializing in Linux technologies. 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!
+
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!
+
@@ -110,12 +144,6 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
systems with a limited number of configurations. Therefore, if you
try rEFInd and run into bugs, please report them to me!
-
I have little talent with graphics manipulation programs, so
- rEFInd's boot logo, such as it is, is pretty weak. If you have
- artistic talent and would like to create a rEFInd logo, please feel
- free to send it to me. I won't make any final decision about
- changes until at least June 30 of 2012.
-
rEFIt's original design, and hence rEFInd's design, enables easy
theming by replacing icon files. If you'd like to design a new
theme for rEFInd, feel free to submit it. I might or might not
@@ -131,52 +159,86 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
-
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.
-
-
The code could be more flexible in its handling of the sizes of
- various graphical elements, and particularly drawn text. Prior to
- version 0.2.2, submenu text was invisible on UEFI-based PCs with
- 800x600 and smaller displays because of an inability to properly
- crop the graphics fields that hold the text. With version 0.2.2,
- I've put a band-aid on this problem by reducing the field size so
- that it now works on 800x600 displays, but smaller displays still
- suffer from this problem. This is just an example of the
- inflexibility of certain layout issues within rEFInd.
-
-
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.
-
-
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.
+
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
+ prefer to have it scan disks and partitions, as the Mac's legacy
+ boot support does. Also, the UEFI legacy boot code presents empty
+ optical drives and uses generic icons rather than OS-specific
+ icons.
+
+
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.
+
+
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.
+
+
The program's font features could be greatly improved by enabling
+ use of a standard font format, by enabling use of non-ASCII
+ characters, and by enabling use of variable-width as well as
+ monospace fonts.
+
+
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
and/or initial RAM disks relative to the rEFInd directory (or the
boot loader's directory, in the case of initrds).
-
+
Currently the background for certain subscreens (such as the
+ information page or submenu listings) is a solid color based on the
+ 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:
-
I'd like to find a way to get rEFInd to launch BIOS boot loaders on
- UEFI-based systems. This option currently works only on
- Macs—or at least, I've not gotten it to work on any of my
- UEFI-based PCs. (I've done some experiments to try to get this to
- work, but so far without success. If you'd like to help on this, e-mail me for my
- thoughts.)
+
I've been receiving reports of blank screens when using rEFInd on
+ some recent Mac models. I've investigated this with the help of one
+ user, and I suspect that Apple has made changes to its firmware
+ that are likely to affect just about any EFI program. I don't have
+ a definitive solution, but at least one user has reported that
+ 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
@@ -184,35 +246,83 @@ 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.
-
-
The Shutdown option works correctly on Macs, but not on UEFI-based PCs.
- On such systems, Shutdown reboots the computer. This should be
- fixed.
+ 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
+ fixed.
The media-ejection feature (F12) should be extended to work on
UEFI-based PCs and early Macs. At the moment, it relies on an
Apple-specific EFI extension, and I know of no standard EFI way to
do it.
+
A couple of Mac users have reported that the brightness-adjustment
+ features in Windows don't work when Windows is booted via rEFInd,
+ but that these features do work when Windows is booted via the
+ Mac's built-in boot manager. Unfortunately, I have no idea what
+ causes this problem, I have no Windows installation on my one
+ (elderly) Mac, and I have no way to debug it. Therefore, it's
+ unlikely that I'll be able to fix this problem myself; but if you
+ 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 re-scan feature renders the user interface immobile until
- the re-scan is complete. This is usually just a second or two,
- but it can be longer if an optical disc needs to be spun up.
- Adding a temporary "scanning media" notice would be helpful.
+
The "scanning for new boot loaders" message that appears during the
+ re-scan feature is primitive. Some sort of dynamic icon would be
+ nice, but perhaps impractical, given the single-tasking nature of
+ EFI.
+
+
On my Mac Mini, launching a shell, returning, and performing a
+ re-scan causes the system to be unable to launch the shell again. I
+ have not observed this behavior on UEFI-based PCs. It seems to be
+ caused by a truncated DevicePath to the shell, which includes the
+ shell's pathname but not the device identifier.
+
+
When specifying a volume by name in dont_scan_dirs,
+ slashes are converted to backslashes in the specification but not
+ in the actual volume name read from disk. Thus, you can't specify a
+ volume by name if it includes a slash (as in Fedora
+ /boot). Workarounds are to rename the volume to omit the slash
+ and to use a filesystem number rather than a volume label.
The code is in need of review to search for memory leaks and
- similar problems.
+ similar problems.
+
+
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
+ test and experiment with this (my only Intel-based Mac doesn't
+ exhibit this problem), so I can't fix this myself. Using
+ pmset to disable the autopoweroff option is
+ claimed
+ 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.
+ 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
+ the NVRAM, and so on. This would be useful in system maintenance
+ and in recovering from boot problems.
+
+
An installation tool for the EFI environment would be useful.
+ A simple EFI shell script might work, but because this function
+ requires access to the bcfg command, this would work
+ only from a version 2 shell or if bcfg were implemented
+ as a standalone program. Another alternative would be a program
+ written in C.
It should be possible to override specific auto-detected boot
loader settings—say, to disable one specific boot loader or
change its icon.
-
A way to read boot options set via efibootmgr,
- bless, or similar options from NVRAM to add to the boot
- set would be useful.
+
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 way to examine and change the NVRAM settings could be useful.
- This would enable a CD-based boot of rEFInd to fix a broken disk
- boot. Perhaps this could be done via a separate tool that could be
- launched much like the shell or gptsync.
-
-
I'd like to give the user the ability to set custom options on a
- single-boot basis, similar to what's possible in GRUB.
+
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.
-
Improvements to the EFI drivers:
+
Improvements to the EFI drivers:
-
The drivers I've built fail to load on a 32-bit Mac Mini; I get an
- "incompatible version" error message at an EFI shell, or an error
- code of 80000019 when rEFInd tries to load them. (These two
- messages are equivalent.) I suspect the problem is related to the
- EFI version 1.x used on the Mac, as opposed to UEFI
- 2.x used on PCs. I'm looking into the problem. In the
- meantime, if you have this problem, I recommend tracking down
- equivalent drivers from other sources. (See the drivers page for some pointers.) I'd
- appreciate hearing from
- you if you have problems along these lines. Please tell me what
- type of computer you're using, and especially the firmware version
- data (from rEFInd's "about" screen). This may help me narrow down
- the cause.
-
-
Drivers for additional filesystems are required. Given the recent
- shift to ext4fs, that should be the priority; however, other Linux
- filesystems, UDF, and perhaps others would all be welcome
- additions. Also along these lines, adding drivers for Linux LVM and
- RAID setups would be useful, too.
-
-
As detailed on the drivers page, there
- are performance issues with the drivers on some systems. I suspect
- that most "real" computers aren't greatly affected (in my tests,
- the problem is worst with VirtualBox, and the next worst is a
- system that uses DUET). Nonetheless,
- I'd like to track down the cause and fix it.
-
-
The driver installation procedure could be improved, perhaps by
- adding support for drivers to the install.sh script.
+
Drivers for additional filesystems are desirable. Only XFS and JFS
+ are missing from the major Linux filesystems. UDF would also be a
+ welcome addition, as might drivers for other OSes (say, for the
+ BSDs, especially if BSD developers create a boot loader similar to
+ Linux's EFI stub loader). Also along these lines, adding drivers
+ for Linux LVM and RAID setups would be useful.
+
+
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.
+
+
When built with the GNU-EFI package, an attempt to load more than
+ one driver on my 32-bit Mac Mini causes the computer to hang. I do
+ not have this problem with 64-bit drivers on my UEFI-based
+ computers. I don't know if this is a 32-bit issue or a Mac issue.
+ This is not relevant if you're using my binary package,
+ since I build it with the TianoCore EDK2, and the drivers built in
+ that way don't exhibit this bug.
+
Improvements to gptsync, refind-install, or other
+ support tools:
+
+
+
+
The gptsync program can return misleading error codes
+ under some circumstances, such as when it makes no changes to the
+ partition table. Fix this.
+
+
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.