Originally written: 3/14/2012; last Web page update:
-4/20/2014, referencing rEFInd 0.7.9
+10/9/2016, referencing rEFInd 0.10.4
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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.
+
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.
+
+
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
- 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.
+
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.
@@ -185,20 +189,8 @@ 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
@@ -210,7 +202,31 @@ 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.
+
+
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.
+ This said, BIOS support is becoming increasingly unimportant as the
+ transition from BIOS to EFI continues, so I'm unlikely to put effort
+ into this issue myself.
+
+
Known bugs that need squashing:
@@ -224,8 +240,20 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
removing rEFInd's drivers has caused the problem to go into
remission.
Another Mac-specific display problem relates to "retina" displays:
+ Some users report that rEFInd comes up in a lower resolution than
+ the screen supports, and that this setting persists into the running
+ OS X instance, and can't be adjusted using the usual OS X means.
+ Unfortunately, I lack the hardware necessary to experiment and find
+ a solution to this problem within rEFInd. Thus, a fix will have to
+ wait for me to get my hands on such hardware (which is not on my
+ immediate purchase list) or until somebody with such hardware and
+ the necessary skills submits a fix. (Note that a fix could
+ conceivably involve passing options to the OS X boot loader or
+ something else that would require trivial or no changes to
+ rEFInd.)
+
+
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
@@ -233,14 +261,10 @@ 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
@@ -261,6 +285,13 @@ 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.
@@ -300,7 +331,13 @@ 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.
+
Currently, debugging rEFInd requires adding Print()
+ statements to the code. Adding a logging facility that supports
+ multiple log levels and writes the output to a file would help with
+ debugging, especially when dealing with problem reports from
+ users.
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.
@@ -330,6 +357,26 @@ href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com
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.
+
+
Better support for touchscreens and/or configurable buttons for
+ rEFInd's actions would enable use of rEFInd on tablet computers that
+ lack complete keyboards. (Version 0.10.4 supports some
+ touchscreens, but this feature relies on support in the firmware,
+ which is not universally present.)
+
+
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
@@ -347,13 +394,19 @@ 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.
+
+
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.
@@ -368,9 +421,6 @@ 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:
@@ -394,13 +444,10 @@ 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
-
-