Return to BSD News archive
Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!news.mira.net.au!Germany.EU.net!howland.reston.ans.net!news.sprintlink.net!neonramp.com!cynjut.neonramp.com!cynjut.neonramp.com!not-for-mail
From: burgess@cynjut.neonramp.com (Dave Burgess)
Newsgroups: comp.unix.bsd.netbsd.announce,comp.unix.bsd.freebsd.announce,comp.answers,news.answers
Subject: [comp.unix.bsd] NetBSD, FreeBSD, and 386BSD (0.1) FAQ (Part 4 of 10)
Supersedes: <386bsd-faq-4-829375208@cynjut.neonramp.com>
Followup-To: comp.unix.bsd.netbsd.misc
Date: 27 Apr 1996 01:00:23 -0500
Organization: Dave's House in Omaha
Lines: 1863
Approved: news-answers-request@MIT.Edu,cgd@sun-lamp.cs.berkeley.edu
Expires: 05/15/96 01:00:07 CDT
Message-ID: <386bsd-faq-4-830584807@cynjut.neonramp.com>
References: <386bsd-faq-1-830584807@cynjut.neonramp.com>
Reply-To: burgess@cynjut.neonramp.com (386bsd FAQ Maintainer)
NNTP-Posting-Host: cynjut.neonramp.com
Keywords: FAQ 386bsd NetBSD FreeBSD !Linux
X-Posting-Frequency: Posted on/about the 13th and the 27th of every month.
Xref: euryale.cc.adfa.oz.au comp.unix.bsd.netbsd.announce:154 comp.unix.bsd.freebsd.announce:212 comp.answers:16423 news.answers:63356
Posted-By: auto-faq 3.1.1.2
Archive-name: 386bsd-faq/part4
Section 3. (Kernel Building and Maintenance)
3.0 System Internals
One of the interesting aspects of *BSD is the fact that it comes
with the complete source. This allows you to make changes to the
system, recompile, and test out your new ideas. This section of
the FAQ describes many of the different aspects of this endeavor
and common problems and pitfalls that are encountered. Kevin Lahey
provided the substantial portion of this section. You can contact
him via E-Mail at (kml@rokkaku.atl.ga.us) or contact Dave Burgess
(burgess@cynjut.neonramp.com).
3.1 Kernel
3.1.1 How do I build a kernel?
The kernel can be compiled in a variety of ways to support different
devices and configurations. Compilation is controlled by a config
file that specifies the characteristics of the kernel. A set of
different config files is located in /sys/i386/conf or
/sys/arch/i386/conf. The configuration file names are in upper case.
To build a particular kernel (in this example, we use the GENERICISA
configuration file in NetBSD or FreeBSD):
% cd /sys/i386/conf
% config GENERICISA
% cd /sys/compile/GENERICISA
% make depend
% make
If you are using 386bsd 0.1, you'll need patch 1 from the patchkit
to get the compilation to work, because the version file isn't
correctly included in the Makefile.
In NetBSD, since there are multiple architectures supported, there
is an architecture line in the middle of the path to these files.
See the build.kernel script in section 3.8 for more information.
Remember, when structures in the kernel change, there are some
programs (ps, top, etc.) that will cease to work correctly. You
will need to recompile these programs as well as the new kernel.
You need to do the following to make sure that your programs get
updated as well as the kernel:
cd /usr/src/include
make install
cd /usr/src/lib/libkvm
make clean && make && make install
cd /usr/src/bin/ps
make clean && make && make install
cd /usr/src/...
3.1.2 I want to do one of the following things:
* add a device not in the distributed kernel (third com
port, additional disk or tape, line printer driver, etc).
* use a patch from the net or the patchkit to fix a kernel bug.
* add another swap device.
* recompile the kernel to remove extraneous devices so that
it takes up less space.
* configure more pseudo-terminals to allow for more xterms
or network logins.
You're going to have to recompile the kernel after you modify the
config file. See section 3.2 below for more information about the
config file in general.
3.1.3 I don't have the source distribution -- how can I rebuild the
kernel?
There are reference sites available, as well as the 'good
net-neighbor' policy, whereby you could make arrangements
with a net neighbor to use a large local machine as a Network
File System (NFS), or allow you to compile a new kernel on
their machine and transfer it to yours. You can also ask for
help from comp.os.386bsd.questions if you get stuck and cannot
make any headway.
3.1.4 Now that I have a kernel, how do I install it?
Your kernel is called /386bsd or /netbsd. Copy the new kernel
from /sys/compile/GENERICISA/386bsd to /, assuming that it is
in that directory. This is relatively straightforward; there
are a couple of things to remember, though. First, if you
really screw up the new kernel, you want to have something to
fall back on, so be sure to save /386bsd to /386bsd.old before
copying in a new kernel. Second, if you just copy the new
kernel over the currently running kernel, funny things can
happen. Be sure to move aside the currently running kernel
before copying over the new one.
There are folks that have reported that overwriting their
current kernel has never caused them any real problems. On the
other hand, if the old kernel was working and the new one
doesn't, and you have made changes that require that old
kernel, it should be available to the system, and saving it
to /386bsd.alt or /386bsd.old are reasonable things to do.
If you are really paranoid, you can mount a new fixit floppy
and replace its kernel with the one you just built, and then
boot from the fixit floppy to make sure everything will work.
This is a pretty good idea if you are making radical changes or
if you are unsure about your changes.
3.1.5 After installing the patchkit and recompiling the kernel with the
option "WD8013", I am no longer able to reboot the machine. A
cold boot (power on) runs fine, but after a reboot no boot drive
is found by the BIOS. Besides having a 16-bit WD/SMC Ethernet
card installed the machines try to boot using either a Adaptec
1742 or 1542 SCSI board to boot from.
This answer was provided by Hellmuth Michaelis (hm@hcshh.hcs.de)
and by Rodney Grimes (rgrimes@acacia).
Remove "option WD8013" from the config files and recompile and
reinstall the kernel.
The reason that option WD8013 often causes this reboot problem is
this:
There is a requirement that all memory within a 128k bank in the
0xA0000 to 0xFFFFF region be either 16-bit or 8-bit. On a cold
boot, the WD8013 boards are reset to 8-bit mode, the POST
(Power On Self Test) passes without error. 386bsd comes up, the
if_we.c driver places the WD8013 in 16-bit mode. Now on a soft boot
when the BIOS runs some quick POST tests it finds a problem in the
0xA000 to 0xF000 region. You probably get a "beep-beep" when this
happens. It means you have a memory size conflict.
The machine has been mis-configured.
This is a little known fact about 16-bit vs 8-bit option cards.
It has caused more than one person to go crazy tracking down
what they swear is a bug in the program. It is not, it is a
flaw in the design of the ISA bus. The signal MEMCS16- must be
returned the same for every 128k block of memory:
A0000-BFFFF Must all be either 8-bit or 16-bit.
B0000-CFFFF Must all be either 8-bit or 16-bit.
D0000-FFFFF Must all be either 8-bit or 16-bit.
In your particular configuration (WD8013 @ cc000) I suspect that
you have another board in the B0000-CFFFFF region that is 8-bit,
i.e. your Adaptec has an 8-bit BIOS on it!
Try moving the board to the 0xD0000 region and see if it works
there, you may still have a problem as many modern system BIOSes
are now 8-bit. If your system BIOS is 8-bit, try shadowing the
system BIOS region at 0xF0000 to 0xFFFFF, this effectively turns
it into a 16-bit BIOS.
Do not attempt to shadow the WD8013, it will cause you many
headaches. In fact, it sometimes helps to turn on BIOS shadowing.
Some BIOSes allow to copy ROM contents to unused RAM pages for
selected 16KB-regions. While it is generally a good idea to turn
BIOS shadowing off, I have also observed that sometimes it helps to
turn shadowing of true ROM regions on.
3.1.6 My system is complaining about stray interrupt 7. Is my machine
going to explode or anything?
No. They are caused by lots of things. They are, as far as
anyone that should be expected to know about this stuff, harmless.
There are ramifications on them being there, but for MOST users
they do not pose a real threat to your operations. For those of
you that are doing REALLY interrupt intensive stuff, you may want
to grab a technical reference and figure out why the 8259 is not
getting reset correctly.
In spite of the number of times this has come up (and people have
even referenced this section) there are still at least two
questions on the net about this. A memorable one was a guy who
was just vehement that the stray int 7 was what was keeping his
system from booting. In fact, he went so far as to say that this
document was practically worthless because I didn't tell him how
to fix it. Of course, once he configured his hard drive controller
so that it was on the right interrupt, his booting problem went
away. I have said it before and I will say it again. For MOST
users they do not pose a real threat to your operations.
I have heard of three people (out of at least 2000) that have
actually have problems so bad that they couldn't proceed. They
bought new computers, and the problem went away.
These stray interrupts are caused by something in the PC.
I have yet to see a convincing explanation of precisely what,
but they are definitely caused by something. There are four
ways to deal with this problem.
1) Ignore them. They are spurious and do not effect the
operation of your computer.
2) Implement the lpt driver. This way, the driver traps
(the lpt driver expects IRQ 7) and then quietly discards them.
That is why when folks implement the lpt driver the 'problem'
goes away. The computer is taught how to ignore them.
3) Do what the original 386bsd code did. Comment out the
diagnostic and associated code that tries to deal with them so
you don't see the error message.
4) Buy a new computer that doesn't cause this problem. It is a
known hardware problem with the 8259 being reset incorrectly in
hardware.
Kalevi Suominen (jks@geom.helsinki.fi) offers this technical
explanation of the 'stray interrupt 7' phenomenom.
In the section of the Intel Peripheral Handbook dealing with
the 8259A there is a description of the 6-step interrupt
sequence for an 80x86 system (and 7-step for an MCS-80/85),
and then the following paragraph:
"If no interrupt request is present at step 4 of either sequence
(i.e., the request was too short in duration) the 8259A will
issue an interrupt level 7. Both the vectoring bytes and the CAS
lines will look like an interrupt level 7 was requested."
This explains how some transient disturbances or improperly
functioning adapter cards could trigger a stray interrupt 7
in a system operating in the *level* interrupt mode (such as
a PS/2 with MCA): An interrupt request will disappear as soon
as the interrupt line goes inactive.
That such interrupts may also occur in a system operating in
the *edge* triggered mode (such as an ordinary PC/AT with ISA)
is a little harder to see. Yet it is possible - even without
malfunctioning hardware - because masking an interrupt request
will hide its presence from the 8259A as well:
1. The interrupt flag (IF) of the 80x86 is reset either
directly (e.g., by a "cli" instruction) or because an
interrupt handler is entered. In the latter case the
corresponding in-service (IS) bit of the 8259A is set
(effectively blocking interrupts of lower priority).
2. The 8259A receives an unmasked interrupt request (IRQn),
and, in case an interrupt is being served and has higher
priority than IRQn, the IS bit of the 8259A is reset by
an end of interrupt (EOI) command. (These steps may occur
in either order.) If IRQn has higher priority (e.g. IRQ0),
no EOI is necessary.
3. The 8259A activates the interrupt (INT) line to the 80x86
(which will ignore it - for the moment).
4. The interrupt mask (IM) bit of the 8259A for IRQn is set.
(A little late, though. The sequence has already started.)
5. The interrupt flag (IF) of the 80x86 is set (either
directly, or as a consequence of e.g. an "iret" instruction).
6. The 80x86 will now acknowledge the INT request by activating
the INTA line of the 8259A.
7. The 8259A will not see the masked IRQn and will continue
by issuing a spurious interrupt of level 7 instead.
The original interrupt request (IRQn) will not be lost, however.
It is preserved by the associated edge sense latch of the 8259A,
and will be acted on after the IM bit has been reset again.
The net result is that a single interrupt request will be
delivered *twice* to the 80x86: first as a stray interrupt 7
and later as the proper interrupt. In particular, it is perfectly
safe to ignore the stray interrupt (other than sending an EOI).
It is just the ghost of an aborted interrupt sequence: the system
was not prepared for it yet.
3.1.7 I keep getting "wd0c: extra interrupt". What does it mean?
It means that the drive was already processing a command
(active) when it recieved an interrupt from the system telling
it to see if it had anything to do. This is mostly harmless
but could indicate that the drive/controller is having problems
if the message appears often.
3.1.8 I keep getting silo overflow messages, but the system doesn't
seem to mind. Is there a problem?
Not exactly. This simply means that the First in first out
buffer is getting too full. I markedly reduced the incidence
of silo overflows on my system by editing dev/isa/com.c to
change the FIFO threshold from 8 to 4 characters. This way, the
buffer gets more attention and reduces the chance of overflowing
the buffer.
3.1.9 I found a bug in the kernel. How do I report it?
Both NetBSD and FreeBSD include a facility called 'bugfiler'.
While the instructions are included in both system, there is
still some apparent confusion about when to use (and when to
NOT use) bugfiler.
Jordan K. Hubbard (jkh@whisker.lotus.ie) provides us with this
short article for FreeBSD.
To send bug reports, you want to use the sendbug(1) command.
The entire package for sending and filing these bugs is known
as "the bugfiler", which is where the confusion stepped in,
but sendbug is definately the command you want to use.
Second, it doesn't take a "net connection" to use sendbug,
since all it does is package up your "bug report form" and mail
it to us; no direct internet connectivity is required, just mail.
So if you can send internet mail you can use sendbug, or you can
also send mail to the `FreeBSD-bugs@freefall.cdrom.com' address
(do NOT send it to FreeBSD.cdrom.com since it will BOUNCE, this
is not the place to send bugs to, just to ftp stuff from!).
NetBSD has a similar facility, but has a different program and
host for bug reports. The program for NetBSD is called send-pr
and is slightly different in several respects. It is part of
the GNATS system, which the NetBSD core developers started using
in February of 1994. It is recommended that NetBSD users see the
man page on send-pr before filing bug reports.
For getting information from GNATS, see the file doc/BUGS.
There is a email interface to the NetBSD PR database. To query
the database send mail to "query-pr@gnats.netbsd.org". The mail
server will send a bug database listing back to the user.
There are several flags that are useful to send to the mail server.
The flags are entered in the "Subject" line:
--summary Display an one-line entry for each bug
--full Display the full entry for each bug
--help Display a help string containing the rest of the flags.
PR The Problem Report number of a particular bug
For example, to send a query about all the bugs:
$ Mail -s "--summary" query-pr@gnats.netbsd.org < /dev/null
If you want to know more about a particular bug, let's say bug 40:
$ Mail -s "--full 40" query-pr@gnats.netbsd.org < /dev/null
John Conklin is trying to get a page set up at the NetBSD WWW site
(www.netbsd.org) that will allow people to interactively query the
bug database. It should be operational soon.
3.1.10 Can someone please give a reasonably clear set of instructions
as to how to get a "current" version of NetBSD running?
First, you will need to get the new files into your source
directory. You can either use the most recently released set of
sources (for an upgrade) or you can start following -current.
Either way, you can use the instructions to build the world (at
the end of this section of the FAQ).
And Theo Deraadt provides this guidance when you get an error
like "init_main.o: Undefined symbol _pdevinit referenced from
text segment."
You need to
(1) install new config
(2) make clean
(3) re-config your kernel
then this goes away
3.2 What exactly is this config file, anyway? What are all of these
cryptic notations?
The config file is the list of all of the optional (and settings
for the mandatory) parts of the kernel. If the system is made
up of static object files which don't change, then all you
should ever need to do is modify the config file, reconfigure
the kernel objects, and relink. Since both NetBSD and FreeBSD
are distributed with source, these files are recompiled and a
kernel is constructed. Some of these have been deprecated, and
may not be in use for a particular version of the system
(i.e. ISO9660 and CD9660 are the same, CD9660 being the newer
version). This is a list of the compile options and
a very brief explanation of what they are used for:
ACCOUNTING # process accounting
ADOSFS # AmigaDOS file system
CCITT # CCITT X.25
CCITT,LLC,HDLC # CCITT protocol suite
CD9660 # ISO 9660 (CDROM) filesystem w/ RockRidge
COMDEF_SPEED=x # default baud on the scn chips
COMPAT_09 # compatibility with NetBSD 0.9
COMPAT_10 # compatability with NetBSD 1.0
COMPAT_43 # 4.3 BSD compatible system calls
COMPAT_44 # compatibility with 4.4BSD binaries
COMPAT_HPUX # HP-UX Binary compatibility (see note)
COMPAT_IBCS2 # Intel Binary Compatibility (see note)
COMPAT_LINUX # Linux Binary Compatibility (see note)
COMPAT_FREEBSD # FreeBSD Binary Compatibility (see note)
COMPAT_NOLABEL # default partitioning for unlabeled disks
COMPAT_NOMID # allow nonvalid machine id executables
# (specifically NetBSD, 386BSD, and BSDI)
COMPAT_OHPUX # Needed at least through HP-UX 7.05 (see note)
COMPAT_SUNOS # Support to run Sun (m68k) executables
COMPAT_SVR4 # System V R4 compatibility (see note)
COMPAT_ULTRIX # compatibility with ULTRIX binaries (see note)
(NOTE: Several of these options include the ability to run both
statically and dynamically linked binaries. Obviously,
you can't run M680*0 binaries on am i386, but the OS
level support is there. See Section 3.n for more
information on dynamically linked executables and the
emulation modes.)
CONFIG_NEW # Use config.new stuff
DDB # Kernel debugger
DEBUG # extra kernel debugging support
DEC_2000_300 # Jensen: 2000/300
DEC_2100_A50 # Avanti: AlphaStation 400 4/233
DEC_3000_300 # Pelican family: 3000/300*
DEC_3000_500 # 3000/[4-9]00
DEVPAGER # device pager (mapped devices)
DEV_RTC # /dev/rtc access to hardware clock
DIAGNOSTIC # Add additional error checking code
DIRECTED_BROADCAST # Broadcast across subnets
DST=x # daylight savings rules (for param.c)
DUMMY_NOPS # Sometimes results in a faster machines
EON # ISO CLNL over IP
ETHER # Ethernet, probably needed
FASTLINKS # fast symbolic links in FFS
FDESC # user file descriptor filesystem
FFS # Berkeley fast file system
FIFO # FIFO operations on vnodes
FPCOPROC # Support for MC68881/MC68882
FPSP # MC68040 floating point support
GATEWAY # IP packet forwarding
GDB # support for normal gdb
GENERIC # Mini-root boot support
GRF_A2024 # Support for the A2024
GRF_AGA # AGA Chip Set
GRF_CL5426 # Cirrus board support (not yet)
GRF_ECS # Enhanced Chip Set
GRF_NTSC # NTSC
GRF_PAL # PAL
I386_CPU # CPU classes; at least one is REQUIRED
I486_CPU # cpu type
INET # IP prototol stack support
INSECURE # Xfree86 requirement
ISO # ISO Networking support
ISOFS # ISO-9660 w/ RockRidge
KERNFS # kernel data-structure filesystem
KFONT_8X11 # 8x11 font
KFONT_8x8 # Use 8x8 font instead of 8x11
KGDB # support for kernel gdb
KGDBDEV=x # device for kernel gdb
KGDBRATE=x # kernel gdb port rate (default 9600)
KTRACE # Add kernel tracing system call
LFS # Log-based filesystem (still experimental)
LKM # loadable kernel modules
LOFS # Loop-back filesystem
M68020 # support for 020/851
M68030 # support for 030
M68040 # support for 040
MACHINE_NONCONTIG # temporary kluge to allow for
# non-contguous memory (on PC)
MAPPEDCOPY # use page mapping for large copyin/copyout
MATH_EMULATE # DX maths emulation
MC68030 # Includes the 020+851
MFS # Memory based filesystem
MROUTING # Multicast routing support
MSDOSFS # MS-DOS filesystem
MULTICAST # Multicast support
NFS # Sun NFS-compatible filesystem
NFSCLIENT # Network File System client
NFSSERVER # Network File System server
NFS_BOOT_RWSIZE=1024 # Size of NFS boot
NKMEMCLUSTERS=x # Size of kernel malloc area
NS # Xerox XNS
NSIP # XNS over IP
NULLFS # Loopback filesystem
PANICBUTTON # Two fast <reset>s on console dump kernel
PANICWAIT # Require keystroke to dump/reboot
PCVT_NETBSD # Pseudo Console VT220 support
PCVT_NOFASTSCROLL # Disable fast scrolling on pcvt's
PORTAL # Portal filesystem
PROCFS # /proc filesystem
QUOTA # file system quotas
RAMD_ADR=x # Adr of the boot strap ram disk
RAMD_SIZE=x # Size of the boot strap ram disk
RCONSOLE # fast rasterop console
RETINACONSOLE # enable code to allow retina to be console
RETINA_SPEED_HACK # enable fast scroll code, may not work
SBPRO # Sound Blaster Pro support
SCSI # Support for SCSI disks
SCSIDEBUG # Add SCSI debugging statements
SHMMAXPGS=x # 1024 pages is the default
SWAPPAGER # Pager for swap device
SYSCALL_DEBUG # debug all syscalls.
SYSVMSG # System V messages
SYSVSEM # System V like semaphores
SYSVSHM # System V shared memory
TCP_COMPAT_42 # compatibility with 4.2BSD TCP/IP
TIMEZONE=x # minutes west of GMT (for param.c)
TPIP # ARGO TP networking support
UCONSOLE # Anyone can do TIOCCONS
UMAPFS # uid/gid remapping filesystem
UNION # Union filesystem
USER_LDT # user-settable LDT; used by WINE
VNODEPAGER # Pager for vnodes
XSERVER # Xserver support
3.2.1 Okay, fine. Why shouldn't I just add every device I can find to
the kernel, so I'll never have to recompile this again?
Because it takes up space. The kernel is wired into memory, so
every byte it uses comes out of the pool of memory for everything
else. It can't page out sections that aren't in use. If your
kernel is larger than 640K, then it can't be loaded. You'll need
to use Julian Elischer's bootblocks to put it in high memory, which
seem to be fairly complex. Installing them (once they are
compiled) is as easy as using disklabel.
Newer versions of the *BSD kith provide the capability to build
a kernel that is larger than 640K. Complete instructions are
provided in the appropriate systems.
3.2.2 What should I remove from the kernel?
What do you need? If you only have an SCSI controller, you don't
need the wd0 device; if you have another kind of disk controller,
you don't need sd0. Unless you actually HAVE more than one Ethernet
controller, you should comment out all but one of them. If you don't
have an ethernet controller, you don't need any of the controllers or
NFS compiled in. Without a CD-ROM, ISOFS is kind of pointless. Just
look at what you have and think about what you really need.
3.2.3 I can't get enough remote login sessions or xterm sessions. I also
can only get four sessions working at a time. What can I do?
Increase the count of pseudo-terminals --
pseudo-device pty 12 # or whatever
Every pseudo terminal should have a /dev/pty* entry. If you have 12
pseudo terminals, you should also have at least 12 pty devices in the
/dev directory. The MAKEDEV script in /dev will create as many pseudo-
terminals as you tell it to.
3.2.4 How do I get ddb, the kernel debugger, compiled into the kernel
and running?
If you are using older versions of the 386BSD family, you will
need to add a line in your config file that looks like this:
device-pseudo ddb
If you are using a more recent version (the division is pretty
unclear about when the switch was made) and do not have any
device-pseudo entries, you will need to add the line:
options DDB
to your config file.
Build the kernel, then run dbsym on it:
% dbsym ./386bsd
Install it and go for it. Ctl-Alt-Esc drops you into the debugger.
Note: DDB as shipped originally is a memory hog, and it is very
difficult to get a kernel small enough with enough fun things in it
to debug in 640K
On the NetBSD-sparc system, the L1-A is used by the the DDB
routines to drop you into the debugger.
3.2.5 I'm getting all kinds of errors when I try to build a new
version of GCC. How can I upgrade GCC to the most current version?
Yes, this will happen on most architectures on the first compile
of src/gnu/usr.bin/gcc/libgcc. As was stated in the mailing
list before, when you get to this error:
1) run a 'make' in the gcc directory. It will error out (most
likely) on libgcc.
1) Do a 'make install' at this point to install at least gcc,
cpp, and cc1.
2) go back and compile in src/gnu/usr.bin/gcc/ WITHOUT doing
a "make clean"
3) install everything in src/gnu/usr.bin/gcc
3.2.6 Can I patch the current running OS image?
In general, I think, the answer is no. The prevailing philosophy
seems to be that one should use sysctl for such things, but that
requires that one has already compiled in the ability to change
the specific variable in question. (I discovered this when I
wanted to patch tickadj at runtime; I added it to kernfs, and
when I offered the patches (which are quite small) I was told
sysctl was the `correct' way. What's incorrect about /kern was
never quite explained; the closest anyone came was to invoke
internationalization concerns. Of course, using /kern also
requires having compiled in support for tweaking the variable
you want to change.)
Besides, unless you've patched securelevel, I don't think there
is any good way to twiddle variables in the running kernel.
/dev/{,k}mem are, I believe, read-only once init sets securelevel
to 1.
Der Mouse
(mouse@collatz.mcrcim.mcgill.edu)
3.2.6 Can I have more than one config file? Should I rename it to something
else? Any other hints?
You can create as many (or as few) config files as you desire. The
system, once the patchkit is applied, will have between 10 and 15,
each of which implements certain functions or features. In addition,
the normal place for the patchkit to make changes to the config files
is in the GENERICISA file. Since this file should remain unchanged
and available, it is always a good idea to copy this file to a
meaningful name and modify that file. In other words, change every
reference in 3.1.1 from GENERICISA to HAL (or whatever you call your
system).
One final note. Every /sys/compile directory takes up 800K or so;
you might want to watch to see how big these all get.
3.2.7 What is the meaning of the trap codes I get in panic messages?
Sometimes this message appears in the form "trap type nn".
That message means that the system received an unexpected (and
unwanted) trap that probably indicates some form of kernel bug.
These traps, are usually received from the kernel, in which case
the trap.h definitions should be used.
The number (which appears in place of "nn" above) is *NOT* the
i386 or i386 trap type, it is a BSD-defined trap type number.
The definitions of the various trap types can be found in
/usr/include/machine/trap.h.
two of the more common ones are:
9 T_PROTFLT protection fault
(The kernel tried executing code
which was not noted as "executable".
This happens if the kernel jumps to
a bogus location.)
12 T_PAGEFLT page fault
(The kernel tried to access a bogus
area of memory. This can happen if
an invalid pointer is dereferenced.)
This is a list of i386 trap codes (just to confuse the issue).
Trap 0 Divide Error
The DIV or IDIV instruction is executed with a zero denominator
or the quotient is too large for the destination operand.
Trap 1 Debug Exceptions
Used in conjunction with DR6 and DR7, The following flags
need to be tested to determine what caused the trap:
BS=1 Single-step trap
B0=1 AND (GE0=1 or LE0=1) Breakpoint, DR0, LEN0, R/W0
B1=1 AND (GE1=1 or LE1=1) Breakpoint, DR1, LEN1, R/W1
B2=1 AND (GE2=1 or LE2=1) Breakpoint, DR2, LEN2, R/W2
B3=1 AND (GE3=1 or LE3=1) Breakpoint, DR3, LEN3, R/W3
BD=1 Debug registers not available,
in use by ICE-386
BT=1 Task Switch
Trap 2 NMI Interrupt
On PC/AT systems, the NMI input to the CPU is usually
connected to the main memory parity circuit. By the time the
error signal is generated, the data may have already been
used in an instruction, so it isn't possible to reliably
recover.
And some not-so-common causes (from various sources):
PS50+ : I/O channel check, system watch-dog timer
time-out interrupt, DMA timer time-out interrupt
parity errors on any 8-bit or 16-bit board pulling the
IOCHCK* line low
first generation of auto-switching EGA cards used NMI
to trap port access for CGA emulation (e.g., ATI's EGA
Wonder)
Zeos Notebook low battery (perhaps other battery-based
computers)
Trap 3 Breakpoint
The result of executing an INT 3 instruction. MS-DOS and
Windows and some other non-386 systems use this for debugging.
Code specific to the 386 and later processors should use
the debugging features tied to Trap 1.
Trap 4 INT0 Detected Overflow
Occurs if an INT0 instruction is executed and the overflow
flag (OF) is currently set.
Trap 5 BOUND Range Exceeded
Occurs if the BOUND instruction is executed and the array
index points beyond the area of memory containing the array
being tested.
Trap 6 Invalid Opcode
The value read at CS:IP is not a valid opcode.
Trap 7 Coprocessor Not Available
This occurs if the processor fetches an instruction that is
for the coprocessor and no coprocessor is present.
Trap 8 Double Exception (Fault)
An exception occurred while trying to execute the handler
for a prior exception. Example, an application causes a
General Protection Fault (13) and the area of memory where
the GPF handler should be is flagged not-present (paged-out?).
The double-fault handler is invoked in these conditions.
If a fault occurs while trying to run the double-fault handler,
a triple-fault occurs and the CPU resets.
The rules for deciding if a double-fault should occur or
if the two faults can be handled serially are discussed in
more detail in the Intel song book.
Trap 9 Coprocessor Segment Overrun
A page or segment violation occurred while transferring
the middle part of a coprocessor operand to the NPX.
Trap 10 Invalid Task State Segment
During a task switch, the new TSS was invalid. Here is
a table of conditions that Invalidate the TSS:
TSS id + EXT The limit in the TSS descriptor is < 103
LTD id + EXT Invalid LDT selector or LDT not present
SS id + EXT Stack segment selector is outside table limit
SS id + EXT Stack segment is not a writable segment
SS id + EXT Stack segment DPL does not match new CPL
SS id + EXT Stack segment selector RPL <> CPL
CS id + EXT Code segment is outside table limit
CS id + EXT Code segment selector does not refer to
code segment
CS id + EXT DPL of non-conforming code segment <> new CPL
CS id + EXT CPL of conforming code segment > new CPL
DS/ES/FS/GS id + EXT DS, ES, FS or GS segment selector is
outside table limits
DS/ES/FS/FS id + EXT DS, ES, FS, or GS is not readable
segment
Trap 11 Segment Not Present
Occurs when the "present" bit of a descriptor is zero.
This can occur while loading any of these segment registers
CS, DS, ES, FS, or GS. Loading SS causes a Stack fault.
Also occurs when attempting to use a gate descriptor that is
marked "not present", and if attempting to load the LDT with
an LLDT instruction. Note that loading the LDT during a
task switch causes an "invalid TSS" trap.
Trap 12 Stack Fault
A limit violation relating to an address referenced off
the SS register. Includes POP, PUSH, ENTER and LEAVE
opcodes, as well as references such as MOV AX,[BP+8]
(which has an implied SS:).
Also causes by loading SS with a descriptor that is marked
"not present".
Trap 13 General Protection Fault (GPF)
Americas Favorite, in the Windows 3.0 world, it is known as
the UAE error. The instruction tried to access data out of
the bounds designated by the descriptors. The access that
failed can be a read, write or instruction fetch. There are
15 classifications of GPFs:
1. Exceeding segment limit when using CS, DE, ES, FS or GS.
2. Exceeding segment limit when referencing a descriptor
table.
3. Transferring control to a segment that is not executable.
4. Writing into a read-only data segment or into a code
segment.
5. Reading from an execute-only segment.
6. Loading the SS register with a read-only descriptor
(unless the selector comes from the TSS during a task
switch, in which case a TSS exception occurs.)
7. Loading SS, DS, ES, FS or GS with the descriptor of a
system segment.
8. Loading, DS, ES, FS or GS with the descriptor of an
executable segment that is not also readable.
9. Loading SS with the descriptor of an executable segment.
10. Accessing memory via, DS, ES, FS or GS when the segment
register contains a null selector.
11. Switching to a busy task.
12. Violating privilege rules.
13. Loading CR0 with a PG=1 and PE=0.
14. Interrupt or exception via trap or interrupt gate from
V86 mode to privilege level other than zero.
15. Exceeding the instruction limit of 15 bytes (this can
only occur if redundant prefixes are placed before an
instruction).
To determine which condition caused the trap, you need
the instruction, the contents of all associated registers,
particularly the segment registers involved, then the various
LDT, GDT and page control tables. Lots of common coding
errors cause the GPFs. Even a stack imbalance will usually
show up as a GPF. Even MOV AX,7 MOV ES,AX or
MOV AX,5 PUSH AX POP DS will get a GPF error. You can't
use a segment register for "temporary storage" of any
old value the way you could on the 8086. The values loaded
into the segment registers are checked in protected mode.
Trap 14 Page Fault
The page directory or page table entry needed for the address
translation has a zero in the present bit, or the current
procedure does not have sufficient privilege to access the
indicated page.
Trap 15 (reserved)
Trap 16 Coprocessor Error
The coprocessor asserted the ERROR# input pin on the 386
(internal on the 486)
Trap 17 Alignment Check (486 and later)
If enabled, this trap will occur if a data fetch does not
occur on a word boundary. I don't know of any software that
activates this feature yet. I have seen SCO UNIX get this
error on early Cyrix processors, even though SCO had not
enabled the feature.
Trap 18-32 (reserved)
[answered by Frank Durda IV <uhclem@nemesis.lonestar.org> and
jim mullens jcm@ornl.gov -or- mullens@jamsun.ic.ornl.gov]
-------------------------------------------------------------------------------
3.2.8 I have been getting a lot of "virtual memory exhausted" errors when
I am compiling a program with a really big static array. I have
128Meg of memory and 8Gig of swap. How can this be happening?
If you are using Csh, you can simply unlimit your processes in
your system level /etc/csh.cshrc file or your personal .cshrc
file. You can also modify your kernel so that the
amount of memory available is less limiting. J"org Wunsch
(j@tcd-dresden.de) provides us with this brief description:
From a recent posting i just made, regarding the problem how much
virtual memory one could get.
| On the other hand, i've also changed the definitions you
| mentioned. But i didn't like to modify the header files, and
| actually, modifying the values is as easy as:
|
| options "DFLDSIZ='(16 * 1024 * 1024)'"
| options "MAXDSIZ='(64 * 1024 * 1024)'"
|
| Include the above lines into your kernel's config file, reconfig
| and rebuild it.
|
This is just a hint for those people poking around with compiling
large source files. Especially, due to some gcc problems with large
static arrays, compiling X applications with huge bitmaps would
cause virtual memory trouble. Increasing the limits (o'course, as
long as the h/w resources suffice) could help there.
The default definitions for the above parameters are found in
/usr/include/machine/vmparam.h.
3.2.9 Where can I learn more about all this?
We've skipped over a lot of details here; the straight dope comes from
"Building Berkeley UNIX Kernels with Config", by Samuel J. Leffler and
Michael J. Karels.
3.2.10 Has the method for system call changed?
Q. Is there something special with the order I need to update
binaries and libraries in? If I drop in the new libc, everything
gives me a bus error. Both shared and static do this.
A. On the port-i386 list, Charles Hannum discussed changing the
system call mechanism (doing it via an INT instead of a call
gate). Looking at src/lib/libc/arch/i386/sys/syscall.S, it looks
like this change is in. Your binaries are (if you are using an
old kernel) probably crashing at each system call now.
So.. first compiling a new kernel with COMPAT_10 in it should make
your newly linked binaries work, I guess (have not recompiled since
the update myself yet). Also don't forget that you need to use
config.new now.
So, the answer is Yes, the mechanism for system calls has
changed, but the old method (using a call gate) is still
available by specifying COMPAT_10 in your configuration file.
3.2.11 Does anyone have a system building script that takes things like
building a new config and multiple config files into account?
This is the program that I use to rebuild my kernel. See the note
in the file about my 'test' program. You may elect to build a
new config every time, or not, depending on your requirements.
#! /bin/sh
#
# Script to rebuild the kernel.
#
if [ `whoami` != 'root' ] ; then
echo 'You must be root to successfully proceed from this point'
exit 1
fi
#
# Set up the environment
#
if [ X$MACHINE_ARCH = "X" ] ; then
MACHINE_ARCH=i386
fi
if [ -f /netbsd ] ; then
ARCHDIR='/arch'
fi
#
# Rebuild Config
#
# I am using a modified test(1) that allows for file date comparisons.
# You can either get my patches (if they aren't already included),
# modify test() yourself, or get the GNU ShellUtils test(1) program.
#
if [ /usr/src/usr.sbin/config -ot /usr/sbin/config ] ; then
echo "Config Up To Date"
else
cd /usr/src/usr.sbin/config
make clean
make depend
make
make install
fi
cd /sys
make
make install
#
# Modify the local Configuration File
#
echo `tput clr`
cd /sys$ARCHDIR/i386/conf
if [ "X$CONFIG_NAME" = "X" ]; then
CONFIG_NAME=GENERIC
fi
if [ "X$1" = "X" ]; then
echo "Configuration Files available:"
ls [A-Z]*
echo " "
echo -n "Enter the name of the config file to use: "
read CONFIG_NAME
echo
else
CONFIG_NAME=$1
fi
if [ ! -f $CONFIG_NAME ]; then
cp GENERIC $CONFIG_NAME
fi
echo "Modifying $CONFIG_NAME config file"
echo -n "Press return to continue (q to quit) "
read ans
ans=`echo $ans | cut -c1 | tr 'QqYy' 'qqqq'`
if [ "X$ans" = "Xq" ] ; then
exit 0
fi
vi $CONFIG_NAME
#config.new $CONFIG_NAME
config $CONFIG_NAME
COMPILE_DIR=/sys$ARCHDIR/i386/compile/$CONFIG_NAME
cd $COMPILE_DIR
make depend
make
if [ $? -ge 1 ] ; then
echo "Errors encountered"
else
if [ -f netbsd ] ; then
PROGNAME=netbsd
else
if [ -f freebsd ] ; then
PROGNAME=freebsd
else
PROGNAME=386bsd
fi
fi
echo `tput clr`
echo ""
echo " Manual Installation is recommended. The following files should be"
echo "copied/linked/moved to the root directory. The following steps are"
echo "suggested:"
echo ""
echo " mv /$PROGNAME /$PROGNAME.old"
echo " mv $COMPILE_DIR/$PROGNAME /$PROGNAME"
echo " reboot"
echo ""
echo "Remember that the new kernel changes will not take place until you "
echo "re-boot the system."
fi
3.2.12 How do I upgrade from my release version of NetBSD (and
probably FreeBSD) to the '-current' development sources?
These 'upgrading instructions' are from Alistair G. Crooks
(agc@uts.amdahl.com) Alistair G. Crooks) and were correct as of
the 26th of June 1995:
# Remember to make yourself a new config (not config.old) kernel
# config file.
#
# Make sure you have COMPAT_10 as part of your kernel config
# options.
# This assumes that the -current source is in /usr/src
(cd /usr/src/usr.sbin/config
make && make install && make cleandir)
# if you don't do this, config of your kernel config file will
# fail with errors in files.i386
(cd /usr/src/gnu/usr.bin/gas ; make && make install && make cleandir)
# if you don't do this, you won't be able to build locore.s, with
# errors about cpuid instruction not found
(cd /sys/arch/i386/conf ; config MYKERNEL)
(cd /sys/arch/i386/compile/MYKERNEL ; make depend && make)
# copy new kernel to /, and boot off it
(cd /usr/src/share/mk ; make install)
# if you don't do this, you'll get errors building gcc, when it
# doesn't know how to make the manual pages (don't know how to
# make gcc.0)
(cd /usr/src/gnu/usr.bin/gcc2 ; make && make install && make cleandir)
# Bernd Wiserner says that the ld.so that will be built next will
# work only with libc.so.12.0, not with libc.so.12.3
# His instructions to make a working ld.so follow:
# Do NOT run ldconfig while doing the folowing 5 lines ...
(cd /usr/src/include ; make && make install)
cp -p /usr/libexec/ld.so /usr/libexec/ld.so.good
(cd /usr/src/gnu/usr.bin/ld ; make && make install && make cleandir)
cp -p /usr/libexec/ld.so.good /usr/libexec/ld.so
(cd /usr/src/lib ; make && make install && make cleandir)
# Then build ld.so again ...
(cd /usr/src/gnu/usr.bin/ld ; make && make install && make cleandir)
# Thanks, Bernd...
# it was at this stage that I got REALLY fed up with the
# sh: warning: running as root with dot in PATH
(cd /usr/src/bin/sh ; make && make install && make cleandir)
# and now back to the beginning and make the world
(cd /usr/src/bin ; make && make install && make cleandir)
(cd /usr/src/sbin ; make && make install && make cleandir)
mkdir /usr/share/doc/usd/13.viref
# otherwise "make install" in /usr/src/usr.bin will fail because
# the destination directory doesn't exist - from Tom Thai
# if you're using the obj directory hierarchy, use the
# initscan.c from the obj directory, otherwise use the initscan.c
# that was created here.
cd /usr/src/usr.bin/lex
if test -d /usr/src/usr.bin/lex/obj ; then
cp initscan.c obj/scan.c
else
cp initscan.c scan.c
fi
# if you don't, then lex won't be built
(cd /usr/src/usr.bin ; make && make install && make cleandir)
(cd /usr/src/usr.sbin ; make && make install && make cleandir)
(cd /usr/src/libexec ; make && make install && make cleandir)
(cd /usr/src/gnu ; make && make install && make cleandir)
(cd /usr/src/share ; make && make install && make cleandir)
mkdir /usr/share/doc/usd/30.rogue /usr/share/doc/usd/31.trek
# otherwise "make install" in /usr/src/games will fail
# actually, last time I tried this, the dirs were already there - agc
(cd /usr/src/games ; make && make install && make cleandir)
3.2.13 Is there a Makefile that does all that happy world-building
stuff?
# makefile for building -current, based on build sequence from
# Alistair G. Crooks (agc@uts.amdahl.com)
# <sjg@zen.void.oz.au>
# use this one to see what would be done.
#MAKE=echo make
MAKE=make
all: .all.done
# dirs to be done _before_ we can boot a new kernel
INIT_DIRS=usr.sbin/config.new gnu/usr.bin/gas
.init.done:
@set -x; for t in $(INIT_DIRS); do \
f=`basename $$t`; test -f .$$f.done || {\
(cd $$t; $(MAKE) && $(MAKE) install) && \
touch .$$f.done || exit 1; }; \
done
touch $@
.kernel.done: .init.done
@echo "You should"; echo "cd sys/arch/${MACHINE}/conf"
@CONF=`uname -n | cut -d. -f1 | tr 'a-z' 'A-Z'`; \
echo cp GENERIC $$CONF; echo vi $$CONF; echo config.new $$CONF;\
echo cd ../compile/$$CONF; echo "make depend && make"
@echo install the new kernel and reboot, then come here and
@echo touch $@
# dirs to be done _after_ booting a new kernel
PREP_DIRS=share/mk gnu/usr.bin/gcc2 include gnu/usr.bin/ld lib
.prep.done: .kernel.done
@set -x; for t in $(PREP_DIRS); do \
f=`basename $$t`; test -f .$$f.done || {\
(cd $$t; $(MAKE) && $(MAKE) install) && \
touch .$$f.done || exit 1; }; \
done
touch $@
# dirs that should be re-built now that we have new libs
CLEAN_DIRS=$(INIT_DIRS) gnu/usr.bin/gcc2 gnu/usr.bin/ld
.cleandirs.done: .prep.done
@set -x; for t in $(CLEAN_DIRS); do \
(cd $$t; $(MAKE) cleandir); \
done
touch $@
# the rest...
ALL_DIRS=bin sbin usr.bin usr.sbin libexec gnu share games
.all.done: .cleandirs.done
@set -x; for t in $(ALL_DIRS); do \
f=`basename $$t`; test -f .$$f.done || {\
(cd $$t; $(MAKE) && $(MAKE) install) && \
touch .$$f.done || exit 1; }; \
done
touch $@
3.3 X11/XFree86/XS3
3.3.1 What options should I define to get the X extensions included?
Once you have applied the patch kit, the only thing left to do is to
modify the config file to include the following line:
options XSERVER, UCONSOLE
recompile the kernel and the kernel should support X.
3.3.2 Where can I get the FAQ for 'X'?
Steve Kotsopoulos' general 'X on Intel-based Unix' FAQ
available by anonymous ftp from export.lcs.mit.edu in
/contrib/faq/Intel-Unix-X-faq.
3.3.3 Why does X drop characters when using xdm? When I run xdm
from the console, it keeps losing keystrokes and the shift keys
don't always work. Why?
You need to run xdm with the -nodaemon flag. The reason is
xdm normally detaches from the keyboard. This allows other
processes (like getty) to return to reading from the keyboard.
A race condition results, where some keystrokes are sent to
xdm and others are sent to other processes. Using the
-nodaemon flag causes xdm to stay attached to the keyboard
so no other process can use it. This answer comes from Michael
C. Newell (root@wanderer.nsi.nasa.gov)
This bit of trivia is also covered in detail in the X FAQ and
the README that accompanies XFree86.
3.3.4 What does the error 'netscape: uname() failed; can't tell what
system we're running on' from the BSDi version of 'netscape'
really mean?
Netscape is a BSDI1.1 / 4.3BSD-net2 level binary. BSDI uses a
slightly different uname than NetBSD or FreeBSD. There is a
patch that has been successfully made to FreeBSD which gives
them the same functionality as the BSDi uname() is generating.
In case you were wondering, this is where the information is
used - this is a dump of the inital HTTP request packet that
Netscape sent when fetching http://home.netscape.com/
GET / HTTP/1.0
User-Agent: Mozilla/1.1N (X11; I; FreeBSD 2.0-BUILT-1995060 i386)
Accept: */*
Accept: image/gif
Accept: image/x-xbitmap
Accept: image/jpeg
Without this patch, it includes this instead:
User-Agent: Mozilla/1.1N (X11; I; BSD/386 uname failed)
(If Netscape are logging this, I'd rather them know which were
FreeBSD users instead of mistakenly counting them as BSD/386 users.)
3.3.5 Under NetBSD and FreeBSD, xlock (or any other program that uses
passwords) fails to validate user passwords. Anyone know why?
OK, first off, make sure you're using the latest version of
xlock. If you've pulled it out of the /ports/ distribution then
you've got version 1.14. This is woefully ancient, so get the
latest, which at the time of writing is 2.7 (just do an archie
search for 'xlockmore-2.7' to find it).
Get this, compile it up and *make sure it's setuid root*. So,
after you've copied it into /usr/X11R6/bin or wherever, do the
following:
# chown root.wheel ./xlock
# chmod 4755 ./xlock
After that, it should work fine. The problem is that without
being setuid root xlock cannot read the real system passwords.
If you look in /etc/passwd you'll see that the passwords are
all '*'d out, because FreeBSD and NetBSD use shadow passwords.
That's what worked for me. A couple of other suggestions were
raised last time this problem cropped up:
o If you're using a pre-compiled xlock then it might have
been linked against the USA encryption libraries. If you're
outside the States then the encryption libraries are different,
and a US xlock will not be able to read the passwords. The fix
is to get the sources and recompile.
o If you've compiled it from source, made it setuid root, and
it still doesn't work, someone suggested changing the size of
the constant PASSLENGTH in xlock.c from '20' to '40'. I haven't
had to do this, and in v2.7 it's '64' anyway, so it shouldn't
be a problem.
3.4 Compiler and Library routines
There are several questions that could probably be included
here. See also Section 4 for some of the more common 'missing
modules' that also happen to be library routines.
3.4.1 Which C compiler is shipped with my 386BSD derived system?
The standard compiler released with 386bsd 0.1 is GCC 1.38. This
version is considered by many people to be the most stable of
the GCC versions. All other Net/2 derived BSD systems have both
1.38 and 2.4+ available. NetBSD 0.9, for example, is completely
compilable using GCC 2.4.5, which is included as the default
compiler. FreeBSD also ships with the same compiler.
3.4.2 Where is libcompat.a?
The library libcompat.a is (working from memory here) completely
deprecated in 386bsd. The only exceptions might be the re_comp
and re_exec routines, which are discussed in detail in section 4.
In addition, things will be added to libcompat.a as they are
deprecated in the newer versions of NetBSD and FreeBSD. The
getreuid() and setreuid() stuff may be heading that way (if they
aren't there already.
The easiest way around not having a libcompat.a is to simply link
it to a small library, since virtually every other function that
is expected in libcompat.a is already include libc.a.
3.5 I want to run 'XYZA' which is dynamically linked and from 'some
other operating system'. What special things do I have to do to
get it working?
Assuming you are trying to simulate a SVR4 system, you want to
create the '/emul/svr4' directory. You will also want to ensure
the "COMPAT_SVR4" option is in your kernel config file.
With this accomplished, you will need to copy several files into
the emulation directoy. A live example might be best at this
point. Most of this information is include in the
'compat_linux(8)' manpage.
First, set up the '/emul/linux' directory. Within this
directory (and virtually all of the emulation directories) you
will need the following:
etc/ (the emulated /etc directory)
lib/ (the emulated /lib directory)
usr/ (the emulated /usr directory)
From there, the simplest way to populate these directories is to
use a program like 'cpio' or 'tar' to build an archive. Having
a linux machine available will greatly simplify this. Copy
(basically everything from the Linux (or whatever) /etc and /lib
directories.
Any executables that you need from the Linux system should then
be copied into an appropriate place in the usr/ directory. For
example, when creating the Linux Doom system on NetBSD, you need
to have the following files (which should all come from the
Linux Doom distribution).
usr/X11R6/lib
libX11.so.6.0
usr/bin:
as86
ld86
usr/games/doom
README.linuxx
doom1.wad
linuxxdoom
sndserver.old
With Doom specifically, you may need to set 'DOOMWAD' (or
whatever it is) to usr/games/doom for it to work correctly.
In addition to the 'X' version, the native version should also
work (with recent versions of NetBSD (1.1+)
3.6 You promised to talk about timezones below. Are you going to?
>I've seen lots of stuff about timezone's being a bit dodgy,
>especially with most European timezones changing over to DST on
>the 27th March. I must say that that was NOT the case for me -
>pumpy (the author's system) is running off the
>/usr/share/zoneinfo/GB-Eire timezone file, (symbolically) linked
>to /etc/localtime, the CMOS clock is running off GMT, and the
>kernel is compiled with "timezone 0".
I use /usr/share/zoneinfo/MET as /etc/localtime and have the
kernel configured as
timezone -1 dst 4
(My wife is running DOS on this machine for doom sometimes ;-)
I set this strange dst value after diging in some old ultrix(?)
man pages. There were several dst-changing-method listed and 4
was the code for the central europe one.
This gave me an idea... I use an Ultrix box every day, so why not...
Now, I don't know how closely this applies to NetBSD since
Ultrix is based on a much older version of BSD, and this isn't
for the kernel config, but for an envar of timezone values, but
it's at least somewhat enlightening on possible meanings for
these things. Could someone in the know shed light on how
accurately this models the timezone stuff in the kernel config?
When I did "man timezone" this is what I got (portion of this
quoted from the DEC MIPS Ultrix 4.3a timezone(3) manpage,
slightly hacked by me (Michael L. VanLoon (michaelv@iastate.edu))
STD offset [DST [offset][,start[/time],end[/time]]]
the components of the string have the following meaning:
STD and DST Three or more characters that are the
designation for the standard (STD) or
summer (DST) time zone. Only STD is required;
if DST is missing, then summer time does not apply
in this locale. Upper- and lowercase letters are
explicitly allowed. Any characters except a
leading colon (:), digits, comma (,), minus (-),
plus (+), and ASCII NUL are allowed.
offset Indicates the value to be added to the local
time to arrive at Coordinated Universal Time. The
offset has the form:
hh[:mm[:ss]]
The minutes (mm) and seconds (ss) are optional.
The hour (hh) is required and may be a single
digit. The offset following STD is required. If
no offset follows DST, summer time is assumed to
be one hour ahead of standard time. One or more
digits may be used; the value is always
interpreted as a decimal number. The hour must
be between 0 and 24, and the minutes (and
seconds) - if present - between zero and 59. If
preceded by a "-", the time zone is east of the
Prime Meridian; otherwise it is west (which may
be indicated by an optional preceding "+").
start and end Indicates when to change to and back from summer
time. Start describes the date when the change
from standard to summer time occurs and end
describes the date when the change back
happens. The format of start and end must be
one of the following:
Jn The Julian day n (1 < n < 365). Leap
days are not counted. That is, in all
years, including leap years, February
28 is day 59 and March 1 is day 60. It
is impossible to explicitly refer to
the occasional February 29.
n The zero-based Julian day (0 < n <
365). Leap days are counted, and it is
possible to refer to February 29.
Mm.n.d The nth d day of month m (1 < n < 5,
0 < d < 6, 1 < m < 12). When n is 5 it
refers to the last d day of month m.
Day 0 is Sunday.
time The time field describes the time when,
in current time, the change to or from
summer time occurs. Time has the same
format as offset except that no leading
sign (a minus (-) or a plus (+) sign)
is allowed. The default, if time is not
given, is 02:00:00.
As an example of the previous format, if the TZ environment
variable had the value EST5EDT4,M4.1.0,M10.5.0 it would describe
the rule, which went into effect in 1987, for the Eastern time
zone in the USA. Specifically, EST would be the designation for
standard time, which is 5 hours behind GMT. EDT would be the
designation for DST, which is 4 hours behind GMT. DST starts
on the first Sunday in April and ends on the last Sunday in
October. In both cases, since the time was not specified, the
change to and from DST would occur at the default time of 2:00 AM.
The timezone call remains for compatibility reasons only; it is
impossible to reliably map timezone's arguments (zone, a
`minutes west of GMT' value and DST, a `daylight saving time in
effect' flag) to a time zone abbreviation.
3.6.1 How do you change the timezone on NetBSD (FreeBSD also?)?
Relink /etc/localtime. This will correct the difference from
GMT (or its trendy equivelant) to your local timezone. In
addition, the kernel needs to be modified to take the clock
time in your CMOS into account. Since most folks that run DOS
prefer to have their clocks set to local time, the timezone
hack was introduced to allow the kernel to adjust the CMOS
clock time to GMT. Once GMT has been computed, the
/etc/localtime file can be referenced to determine the
corrected local time.
All generic kernels are built using the offset from California
(why is anyone's guess:-) so just about everyone's clock will
be off by their timezone offset from Berkeley.
Also, it may pay to actually copy the correct timezone file
rather than link it. That way, you clock will be correct even
in single users mode (when the /usr partition is not even
mounted. The disadvantage of this is that anytime the timezone
file gets updated, you will need to make certain that the file
is copied into the /etc directory.
3.6.2 The translation between seconds-since-the-epoch and date
differs by about 18 seconds between BSD and other Unixes when
running ntp; why?
See ntp FAQ. Apparently, the time correction takes leap seconds
into account twice. The timezone files in our system take the
leap seconds into account in the kernel, and nntp takes the
same 18 leap seconds into account when syncing the time.
Because of that, the time will appear to be off by eighteen
seconds. (Henning Schulzrinne)
3.7 How can I implement CVS to track MY changes to the kernel source
tree, yet still follow the -current development tree?
I'll append the scripts I use, but be warned, they may bite you if
you are careless...
The main reason I use cvs import is to handle updates from the
``vendor''. The best way I've found is to import _exactly_ what
was shipped. This means unconfigured, and I put config.h, etc,
in .cvsignore. If I have to modify configure.in then obviously
I commit them :-)
#!/bin/sh
# This is a shell archive.
# remove everything above the "#!/bin/sh" line
# and feed to /bin/sh
# Use -c option to overwrite existing files
#
# Contents:
# README.import
# import.sh
# prune.sh
#
# packed by: <sjg@zen.void.oz.au> on Sat Jun 17 20:00:34 EST 1995
#
PATH=/bin:/usr/bin:/usr/ucb ; export PATH
if test -f README.import -a x$1 != x-c ; then
echo shar: Will not over-write existing file \"README.import\"
else
echo shar: Extracting \"README.import\" \(2902 characters\)
sed 's/^X//' >README.import << '!EOF'
XThe following may be of use to others wanting to use CVS to merge
XNetBSD sources with local changes but are not confident that they have
Xinterpreted the documentation accurately.
X
XMuch thanks to Chris Demetriou (cgd) for taking the time to spell out
Xthe steps he used when merging NetBSD sources without which I might
Xnot have taken the plunge myself :-) The following is based on Chris'
Xtips, though of course any errors are mine.
X
XOk. My NetBSD sources are kept in usr.src, if NetBSD is all
Xyou use CVS for you might want to simply call it src.
X
XI unpack tar files and/or sup into a directory /d2/current.
X
XTo import the entire tree I:
X
Xcd /d2/current/src
X
Xcvs import "-I! " -m "from netbsd-current as of 950508" usr.src NetBSD \
XNetBSD-950508 > /tmp/cvs.out 2>&1
X
XWhere:
Xusr.src is the repository where the imported data goes (so set it
X according to your own needs),
XNetBSD is a vendor tag.
XNetBSD-950508 is a release tag (there can be multiple release tags given).
X
XI use "-I! " as otherise some files that you need (like
Xbin/csh/USD.doc/csh.a) will be ignored.. The space after the ! is
Xneeded.
X
XIt takes quite a while. It is a good idea to save the output to a file.
X
XAt the end you may well get a message like:
X
X cvs checkout -jNetBSD:yesterday -jNetBSD usr.src
X
XThis means there were some conflicts between your local sources and
Xthe import. So I do what it says - but not in my working tree.
X
Xcd /d2/tmp
Xcvs checkout -jNetBSD:yesterday -jNetBSD usr.src > /tmp/merge.out 2>&1
X
XYou can then go find all the files with conflicts.
XEither grep '^C' /tmp/merge.out or find usr.src -name '.#*' -print
XGo edit them to resolce the conflicts. This is usually obvious.
X
XWhen happy.
X
Xcd /d2/tmp/usr.src
Xcvs commit -m"merged local changes with NetBSD-950508"
Xcd ..
Xrm -rf usr.src
X
XOk. Now if you are brave you can:
X
Xcd /usr.src (or whereever your working sources are)
Xcvs update
X
XFinally, you should occasionally make sure you remove old files.
X
XI use a script to do this. It does a diff between files on the NetBSD
Xbranch looking for the latest release tag (eg. NetBSD-950508).
XIf cvs diff remports that a file does not have that tag, it is because
Xit was not present in the import (ie removed).
X
XThe command sequence is:
X
Xcvs diff -s -r NetBSD -r NetBSD-950508 > /tmp/prune.out 2>&1
X
X# check that all went well...
Xcat /tmp/prune.out | awk '/Diffing/ { dir=$NF }
X/NetBSD-/ { file=$NF; print dir "/" file }' > /tmp/pruned
X
Xcat /tmp/pruned | xargs cvs tag -d NetBSD
Xcat /tmp/pruned | xargs rm -f
Xcat /tmp/pruned | xargs cvs delete
X
XNote that this is a slow process on a 486DX33! So don't plan on
Xmerging everything very often. Folk who mainly hack the kernel can do
Xsrc/sys more frequently. The sequence is analogous eg.
X
Xcd /d2/current/src/sys
X
Xcvs import "-I! " -m "from netbsd-current as of 950508" usr.src/sys NetBSD \
XNetBSD-950508 > /tmp/cvs.out 2>&1
X
Xetc.
X
XHope this helps.
X
X--sjg
!EOF
if test 2902 -ne `wc -c < README.import`; then
echo shar: \"README.import\" unpacked with wrong size!
fi
fi
if test -f import.sh -a x$1 != x-c ; then
echo shar: Will not over-write existing file \"import.sh\"
else
echo shar: Extracting \"import.sh\" \(290 characters\)
sed 's/^X//' >import.sh << '!EOF'
X:
Xtoday=`date '+%y%m%d'`
X
Xrep=${1:-usr.src}
X
X# -I! doesn't work, it needs a space after the !
Xcvs import "-I! " -m "from netbsd-current as of $today" $rep NetBSD NetBSD-$today
X
X# cd somewhere
X# cvs checkout -jNetBSD:yesterday -jNetBSD usr.src > /tmp/cvs.out 2>&1
X# merge changes and commit
!EOF
if test 290 -ne `wc -c < import.sh`; then
echo shar: \"import.sh\" unpacked with wrong size!
fi
chmod +x import.sh
fi
if test -f prune.sh -a x$1 != x-c ; then
echo shar: Will not over-write existing file \"prune.sh\"
else
echo shar: Extracting \"prune.sh\" \(491 characters\)
sed 's/^X//' >prune.sh << '!EOF'
X:
Xthen=${1:-`date '+%y%m%d'`}
XTF=/tmp/prune.$$
XTF2=/tmp/prune2.$$
X#S=-s
XS=
X
Xcase `echo -n .` in -n*) N=; C="\c";; *) N=-n; C=;; esac
X
Xask () { echo $N "${2:-$1?} "$C; read $1; }
X
Xcvs diff $S -r NetBSD -r NetBSD-$then > $TF 2>&1 || cat $TF >&2
X
Xcat $TF | awk '/Diffing/ { dir=$NF } /NetBSD-/ { file=$NF; print dir "/" file }' > $TF2
X
Xcat $TF2
Xask proceed
Xcase "$proceed" in
X[yY]*)
Xcat $TF2 | xargs cvs tag -d NetBSD
Xcat $TF2 | xargs rm -f
Xcat $TF2 | xargs cvs delete
X;;
Xesac
Xrm -f $TF $TF2
!EOF
if test 491 -ne `wc -c < prune.sh`; then
echo shar: \"prune.sh\" unpacked with wrong size!
fi
chmod +x prune.sh
fi
exit 0
3.8 Optional Op-codes for NetBSD, FreeBSD, and other systems.
MNEMONIC INSTRUCTION
----------------------------------
AAC Alter All Commands
AAR Alter At Random
AB Add Backwards
AFVC Add Finagle's Variable Constant
AIB Attack Innocent Bystander
AWTT Assemble With Tinker Toys
BAC Branch to Alpha Centauri
BAF Blow All Fuses
BAFL Branch And Flush
BBIL Branch on Blown Indicator Light
BBT Branch on Binary Tree
BBW Branch Both Ways
BCF Branch and Catch Fire
BCIL Branch Creating Infinite Loop
BDC Break Down and Cry
BDT Burn Data Tree
BEW Branch Either Way
BF Belch Fire
BH Branch and Hang
BOB Branch On Bug
BOD Beat On the Disk
BOI Bite Operator Immediately
BPDI Be Polite, Don't Interrupt
BPO Branch on Power Off
BRSS Branch on Sunspot
BST Backspace and Stretch Tape
BW Branch on Whim
CDC Close Disk Cover
CDIOOAZ Calm Down, It's Only Ones and Zeros
CEMU Close Eyes and Monkey with User space
CH Create Havoc
CLBR Clobber Register
CM Circulate Memory
CML Compute Meaning of Life
COLB Crash for Operators Lunch Break
CPPR Crumple Printer Paper and Rip
CRASH Continue Running After Stop or Halt
CRB Crash and Burn
CRN Convert to Roman Numerals
CS Crash System
CSL Curse and Swear Loudly
CU Convert to Unary
CVG Convert to Garbage
CWOM Complement Write-Only Memory
CZZC Convert Zone to Zip Code
DBZ Divide By Zero
DC Divide and Conquer
DMNS Do what I Mean, Not what I Say
DMPK Destroy Memory Protect Key
DPMI Declare Programmer Mentally Incompetent
DPR Destroy Program
DTC Destroy This Command
DTE Decrement Telephone Extension
DTVFL Destroy Third Variable From Left
DW Destroy World
ECO Electrocute Computer Operator
EFD Emulate Frisbee Using Disk Pack
EIAO Execute In Any Order
EIOC Execute Invalid Opcode
ENF Emit Noxious Fumes
EO Execute Operator
EROS Erase Read-Only Storage
FLI Flash Lights Impressively
FSM Fold, Spindle and Mutilate
GCAR Get Correct Answer Regardless
GDP Grin Defiantly at Programmer
GFM Go Forth and Multiply
IAE Ignore All Exceptions
IBP Insert Bug and Proceed
ISC Insert Sarcastic Comments
JTZ Jump to Twilight Zone
LCC Load and Clear Core
MAZ Multiply Answer by Zero
MLR Move and Lose Record
MWAG Make Wild-Assed Guess
MWT Malfunction Without Telling
OML Obey Murphy's Laws
PD Play Dead
PDSK Punch Disk
PEHC Punch Extra Holes on Cards
POCL Punch Out Console Lights
POPI Punch Operator Immediately
RA Randomize Answer
RASC Read And Shred Card
RCB Read Command Backwards
RD Reverse Directions
RDA Refuse to Disclose Answer
RDB Run Disk Backwards
RIRG Read Inter-Record Gap
RLI Rotate Left Indefinitely
ROC Randomize Opcodes
RPB Read, Print and Blush
RPM Read Programmer's Mind
RSD On Read Error Self-Destruct
RWCR Rewind Card Reader
SAI Skip All Instructions
SAS Sit and Spin
SCCA Short Circuit on Correct Answer
SFH Set Flags to Half mast
SLMTU=x SLIP MTU size
SLP Sharpen Light Pen
SPS Set Panel Switches
SPSW Scramble Program Status Word
SQPC Sit Quietly and Play with your Crayons
SRDR Shift Right Double Ridiculous
STA Store Anywhere
TARC Take Arithmetic Review Course
TPF Turn Power Off
TPN Turn Power On
UCB Uncouple CPU and Branch
ULDA Unload Accumulator
UP Understand Program
WBT Water Binary Tree
WHFO Wait Until Hell Freezes Over
WI Write Illegibly
WSWW Work in Strange and Wondrous Ways
XSP Execute Systems Programmer
ZAR Zero Any Register
If you have gotten this far, you deserved some humor.
--
Dave Burgess (The man of a thousand E-Mail addresses)
386bsd FAQ Maintainer / SysAdmin for the NetBSD system in my spare bedroom
"Just because something is stupid doesn't mean that there isn't someone
that wants to do it...."