tags/kernel26-2.6.12-alx-r9/README

	Linux kernel release 2.6.xx

These are the release notes for Linux version 2.6.  Read them carefully,
as they tell you what this is all about, explain how to install the
kernel, and what to do if something goes wrong. 

WHAT IS LINUX?

  Linux is a Unix clone written from scratch by Linus Torvalds with
  assistance from a loosely-knit team of hackers across the Net.
  It aims towards POSIX compliance. 

  It has all the features you would expect in a modern fully-fledged
  Unix, including true multitasking, virtual memory, shared libraries,
  demand loading, shared copy-on-write executables, proper memory
  management and TCP/IP networking. 

  It is distributed under the GNU General Public License - see the
  accompanying COPYING file for more details. 

ON WHAT HARDWARE DOES IT RUN?

  Linux was first developed for 386/486-based PCs.  These days it also
  runs on ARMs, DEC Alphas, SUN Sparcs, M68000 machines (like Atari and
  Amiga), MIPS and PowerPC, and others.

DOCUMENTATION:

 - There is a lot of documentation available both in electronic form on
   the Internet and in books, both Linux-specific and pertaining to
   general UNIX questions.  I'd recommend looking into the documentation
   subdirectories on any Linux FTP site for the LDP (Linux Documentation
   Project) books.  This README is not meant to be documentation on the
   system: there are much better sources available.

 - There are various README files in the Documentation/ subdirectory:
   these typically contain kernel-specific installation notes for some 
   drivers for example. See Documentation/00-INDEX for a list of what
   is contained in each file.  Please read the Changes file, as it
   contains information about the problems, which may result by upgrading
   your kernel.

 - The Documentation/DocBook/ subdirectory contains several guides for
   kernel developers and users.  These guides can be rendered in a
   number of formats:  PostScript (.ps), PDF, and HTML, among others.
   After installation, "make psdocs", "make pdfdocs", or "make htmldocs"
   will render the documentation in the requested format.

INSTALLING the kernel:

 - If you install the full sources, put the kernel tarball in a
   directory where you have permissions (eg. your home directory) and
   unpack it:

		gzip -cd linux-2.6.XX.tar.gz | tar xvf -

   Replace "XX" with the version number of the latest kernel.

   Do NOT use the /usr/src/linux area! This area has a (usually
   incomplete) set of kernel headers that are used by the library header
   files.  They should match the library, and not get messed up by
   whatever the kernel-du-jour happens to be.

 - You can also upgrade between 2.6.xx releases by patching.  Patches are
   distributed in the traditional gzip and the new bzip2 format.  To
   install by patching, get all the newer patch files, enter the
   top level directory of the kernel source (linux-2.6.xx) and execute:

		gzip -cd ../patch-2.6.xx.gz | patch -p1

   or
		bzip2 -dc ../patch-2.6.xx.bz2 | patch -p1

   (repeat xx for all versions bigger than the version of your current
   source tree, _in_order_) and you should be ok.  You may want to remove
   the backup files (xxx~ or xxx.orig), and make sure that there are no
   failed patches (xxx# or xxx.rej). If there are, either you or me has
   made a mistake.

   Alternatively, the script patch-kernel can be used to automate this
   process.  It determines the current kernel version and applies any
   patches found.

		linux/scripts/patch-kernel linux

   The first argument in the command above is the location of the
   kernel source.  Patches are applied from the current directory, but
   an alternative directory can be specified as the second argument.

 - Make sure you have no stale .o files and dependencies lying around:

		cd linux
		make mrproper

   You should now have the sources correctly installed.

SOFTWARE REQUIREMENTS

   Compiling and running the 2.6.xx kernels requires up-to-date
   versions of various software packages.  Consult
   Documentation/Changes for the minimum version numbers required
   and how to get updates for these packages.  Beware that using
   excessively old versions of these packages can cause indirect
   errors that are very difficult to track down, so don't assume that
   you can just update packages when obvious problems arise during
   build or operation.

BUILD directory for the kernel:

   When compiling the kernel all output files will per default be
   stored together with the kernel source code.
   Using the option "make O=output/dir" allow you to specify an alternate
   place for the output files (including .config).
   Example:
     kernel source code:	/usr/src/linux-2.6.N
     build directory:		/home/name/build/kernel

   To configure and build the kernel use:
   cd /usr/src/linux-2.6.N
   make O=/home/name/build/kernel menuconfig
   make O=/home/name/build/kernel
   sudo make O=/home/name/build/kernel modules_install install

   Please note: If the 'O=output/dir' option is used then it must be
   used for all invocations of make.

CONFIGURING the kernel:

   Do not skip this step even if you are only upgrading one minor
   version.  New configuration options are added in each release, and
   odd problems will turn up if the configuration files are not set up
   as expected.  If you want to carry your existing configuration to a
   new version with minimal work, use "make oldconfig", which will
   only ask you for the answers to new questions.

 - Alternate configuration commands are:
	"make menuconfig"  Text based color menus, radiolists & dialogs.
	"make xconfig"     X windows (Qt) based configuration tool.
	"make gconfig"     X windows (Gtk) based configuration tool.
	"make oldconfig"   Default all questions based on the contents of
			   your existing ./.config file.
   
	NOTES on "make config":
	- having unnecessary drivers will make the kernel bigger, and can
	  under some circumstances lead to problems: probing for a
	  nonexistent controller card may confuse your other controllers
	- compiling the kernel with "Processor type" set higher than 386
	  will result in a kernel that does NOT work on a 386.  The
	  kernel will detect this on bootup, and give up.
	- A kernel with math-emulation compiled in will still use the
	  coprocessor if one is present: the math emulation will just
	  never get used in that case.  The kernel will be slightly larger,
	  but will work on different machines regardless of whether they
	  have a math coprocessor or not. 
	- the "kernel hacking" configuration details usually result in a
	  bigger or slower kernel (or both), and can even make the kernel
	  less stable by configuring some routines to actively try to
	  break bad code to find kernel problems (kmalloc()).  Thus you
	  should probably answer 'n' to the questions for
          "development", "experimental", or "debugging" features.

 - Check the top Makefile for further site-dependent configuration
   (default SVGA mode etc). 

COMPILING the kernel:

 - Make sure you have gcc 2.95.3 available.
   gcc 2.91.66 (egcs-1.1.2), and gcc 2.7.2.3 are known to miscompile
   some parts of the kernel, and are *no longer supported*.
   Also remember to upgrade your binutils package (for as/ld/nm and company)
   if necessary. For more information, refer to Documentation/Changes.

   Please note that you can still run a.out user programs with this kernel.

 - Do a "make" to create a compressed kernel image. It is also
   possible to do "make install" if you have lilo installed to suit the
   kernel makefiles, but you may want to check your particular lilo setup first.

   To do the actual install you have to be root, but none of the normal
   build should require that. Don't take the name of root in vain.

 - If you configured any of the parts of the kernel as `modules', you
   will also have to do "make modules_install".

 - Keep a backup kernel handy in case something goes wrong.  This is 
   especially true for the development releases, since each new release
   contains new code which has not been debugged.  Make sure you keep a
   backup of the modules corresponding to that kernel, as well.  If you
   are installing a new kernel with the same version number as your
   working kernel, make a backup of your modules directory before you
   do a "make modules_install".

 - In order to boot your new kernel, you'll need to copy the kernel
   image (e.g. .../linux/arch/i386/boot/bzImage after compilation)
   to the place where your regular bootable kernel is found. 

 - Booting a kernel directly from a floppy without the assistance of a
   bootloader such as LILO, is no longer supported.

   If you boot Linux from the hard drive, chances are you use LILO which
   uses the kernel image as specified in the file /etc/lilo.conf.  The
   kernel image file is usually /vmlinuz, /boot/vmlinuz, /bzImage or
   /boot/bzImage.  To use the new kernel, save a copy of the old image
   and copy the new image over the old one.  Then, you MUST RERUN LILO
   to update the loading map!! If you don't, you won't be able to boot
   the new kernel image.

   Reinstalling LILO is usually a matter of running /sbin/lilo. 
   You may wish to edit /etc/lilo.conf to specify an entry for your
   old kernel image (say, /vmlinux.old) in case the new one does not
   work.  See the LILO docs for more information. 

   After reinstalling LILO, you should be all set.  Shutdown the system,
   reboot, and enjoy!

   If you ever need to change the default root device, video mode,
   ramdisk size, etc.  in the kernel image, use the 'rdev' program (or
   alternatively the LILO boot options when appropriate).  No need to
   recompile the kernel to change these parameters. 

 - Reboot with the new kernel and enjoy. 

IF SOMETHING GOES WRONG:

 - If you have problems that seem to be due to kernel bugs, please check
   the file MAINTAINERS to see if there is a particular person associated
   with the part of the kernel that you are having trouble with. If there
   isn't anyone listed there, then the second best thing is to mail
   them to me (torvalds@osdl.org), and possibly to any other relevant
   mailing-list or to the newsgroup.

 - In all bug-reports, *please* tell what kernel you are talking about,
   how to duplicate the problem, and what your setup is (use your common
   sense).  If the problem is new, tell me so, and if the problem is
   old, please try to tell me when you first noticed it.

 - If the bug results in a message like

	unable to handle kernel paging request at address C0000010
	Oops: 0002
	EIP:   0010:XXXXXXXX
	eax: xxxxxxxx   ebx: xxxxxxxx   ecx: xxxxxxxx   edx: xxxxxxxx
	esi: xxxxxxxx   edi: xxxxxxxx   ebp: xxxxxxxx
	ds: xxxx  es: xxxx  fs: xxxx  gs: xxxx
	Pid: xx, process nr: xx
	xx xx xx xx xx xx xx xx xx xx

   or similar kernel debugging information on your screen or in your
   system log, please duplicate it *exactly*.  The dump may look
   incomprehensible to you, but it does contain information that may
   help debugging the problem.  The text above the dump is also
   important: it tells something about why the kernel dumped code (in
   the above example it's due to a bad kernel pointer). More information
   on making sense of the dump is in Documentation/oops-tracing.txt

 - If you compiled the kernel with CONFIG_KALLSYMS you can send the dump
   as is, otherwise you will have to use the "ksymoops" program to make
   sense of the dump.  This utility can be downloaded from
   ftp://ftp.<country>.kernel.org/pub/linux/utils/kernel/ksymoops.
   Alternately you can do the dump lookup by hand:

 - In debugging dumps like the above, it helps enormously if you can
   look up what the EIP value means.  The hex value as such doesn't help
   me or anybody else very much: it will depend on your particular
   kernel setup.  What you should do is take the hex value from the EIP
   line (ignore the "0010:"), and look it up in the kernel namelist to
   see which kernel function contains the offending address.

   To find out the kernel function name, you'll need to find the system
   binary associated with the kernel that exhibited the symptom.  This is
   the file 'linux/vmlinux'.  To extract the namelist and match it against
   the EIP from the kernel crash, do:

		nm vmlinux | sort | less

   This will give you a list of kernel addresses sorted in ascending
   order, from which it is simple to find the function that contains the
   offending address.  Note that the address given by the kernel
   debugging messages will not necessarily match exactly with the
   function addresses (in fact, that is very unlikely), so you can't
   just 'grep' the list: the list will, however, give you the starting
   point of each kernel function, so by looking for the function that
   has a starting address lower than the one you are searching for but
   is followed by a function with a higher address you will find the one
   you want.  In fact, it may be a good idea to include a bit of
   "context" in your problem report, giving a few lines around the
   interesting one. 

   If you for some reason cannot do the above (you have a pre-compiled
   kernel image or similar), telling me as much about your setup as
   possible will help. 

 - Alternately, you can use gdb on a running kernel. (read-only; i.e. you
   cannot change values or set break points.) To do this, first compile the
   kernel with -g; edit arch/i386/Makefile appropriately, then do a "make
   clean". You'll also need to enable CONFIG_PROC_FS (via "make config").

   After you've rebooted with the new kernel, do "gdb vmlinux /proc/kcore".
   You can now use all the usual gdb commands. The command to look up the
   point where your system crashed is "l *0xXXXXXXXX". (Replace the XXXes
   with the EIP value.)

   gdb'ing a non-running kernel currently fails because gdb (wrongly)
   disregards the starting offset for which the kernel is compiled.

1	niro	628	Linux kernel release 2.6.xx
2
3			These are the release notes for Linux version 2.6. Read them carefully,
4			as they tell you what this is all about, explain how to install the
5			kernel, and what to do if something goes wrong.
6
7			WHAT IS LINUX?
8
9			Linux is a Unix clone written from scratch by Linus Torvalds with
10			assistance from a loosely-knit team of hackers across the Net.
11			It aims towards POSIX compliance.
12
13			It has all the features you would expect in a modern fully-fledged
14			Unix, including true multitasking, virtual memory, shared libraries,
15			demand loading, shared copy-on-write executables, proper memory
16			management and TCP/IP networking.
17
18			It is distributed under the GNU General Public License - see the
19			accompanying COPYING file for more details.
20
21			ON WHAT HARDWARE DOES IT RUN?
22
23			Linux was first developed for 386/486-based PCs. These days it also
24			runs on ARMs, DEC Alphas, SUN Sparcs, M68000 machines (like Atari and
25			Amiga), MIPS and PowerPC, and others.
26
27			DOCUMENTATION:
28
29			- There is a lot of documentation available both in electronic form on
30			the Internet and in books, both Linux-specific and pertaining to
31			general UNIX questions. I'd recommend looking into the documentation
32			subdirectories on any Linux FTP site for the LDP (Linux Documentation
33			Project) books. This README is not meant to be documentation on the
34			system: there are much better sources available.
35
36			- There are various README files in the Documentation/ subdirectory:
37			these typically contain kernel-specific installation notes for some
38			drivers for example. See Documentation/00-INDEX for a list of what
39			is contained in each file. Please read the Changes file, as it
40			contains information about the problems, which may result by upgrading
41			your kernel.
42
43			- The Documentation/DocBook/ subdirectory contains several guides for
44			kernel developers and users. These guides can be rendered in a
45			number of formats: PostScript (.ps), PDF, and HTML, among others.
46			After installation, "make psdocs", "make pdfdocs", or "make htmldocs"
47			will render the documentation in the requested format.
48
49			INSTALLING the kernel:
50
51			- If you install the full sources, put the kernel tarball in a
52			directory where you have permissions (eg. your home directory) and
53			unpack it:
54
55			gzip -cd linux-2.6.XX.tar.gz \| tar xvf -
56
57			Replace "XX" with the version number of the latest kernel.
58
59			Do NOT use the /usr/src/linux area! This area has a (usually
60			incomplete) set of kernel headers that are used by the library header
61			files. They should match the library, and not get messed up by
62			whatever the kernel-du-jour happens to be.
63
64			- You can also upgrade between 2.6.xx releases by patching. Patches are
65			distributed in the traditional gzip and the new bzip2 format. To
66			install by patching, get all the newer patch files, enter the
67			top level directory of the kernel source (linux-2.6.xx) and execute:
68
69			gzip -cd ../patch-2.6.xx.gz \| patch -p1
70
71			or
72			bzip2 -dc ../patch-2.6.xx.bz2 \| patch -p1
73
74			(repeat xx for all versions bigger than the version of your current
75			source tree, _in_order_) and you should be ok. You may want to remove
76			the backup files (xxx~ or xxx.orig), and make sure that there are no
77			failed patches (xxx# or xxx.rej). If there are, either you or me has
78			made a mistake.
79
80			Alternatively, the script patch-kernel can be used to automate this
81			process. It determines the current kernel version and applies any
82			patches found.
83
84			linux/scripts/patch-kernel linux
85
86			The first argument in the command above is the location of the
87			kernel source. Patches are applied from the current directory, but
88			an alternative directory can be specified as the second argument.
89
90			- Make sure you have no stale .o files and dependencies lying around:
91
92			cd linux
93			make mrproper
94
95			You should now have the sources correctly installed.
96
97			SOFTWARE REQUIREMENTS
98
99			Compiling and running the 2.6.xx kernels requires up-to-date
100			versions of various software packages. Consult
101			Documentation/Changes for the minimum version numbers required
102			and how to get updates for these packages. Beware that using
103			excessively old versions of these packages can cause indirect
104			errors that are very difficult to track down, so don't assume that
105			you can just update packages when obvious problems arise during
106			build or operation.
107
108			BUILD directory for the kernel:
109
110			When compiling the kernel all output files will per default be
111			stored together with the kernel source code.
112			Using the option "make O=output/dir" allow you to specify an alternate
113			place for the output files (including .config).
114			Example:
115			kernel source code: /usr/src/linux-2.6.N
116			build directory: /home/name/build/kernel
117
118			To configure and build the kernel use:
119			cd /usr/src/linux-2.6.N
120			make O=/home/name/build/kernel menuconfig
121			make O=/home/name/build/kernel
122			sudo make O=/home/name/build/kernel modules_install install
123
124			Please note: If the 'O=output/dir' option is used then it must be
125			used for all invocations of make.
126
127			CONFIGURING the kernel:
128
129			Do not skip this step even if you are only upgrading one minor
130			version. New configuration options are added in each release, and
131			odd problems will turn up if the configuration files are not set up
132			as expected. If you want to carry your existing configuration to a
133			new version with minimal work, use "make oldconfig", which will
134			only ask you for the answers to new questions.
135
136			- Alternate configuration commands are:
137			"make menuconfig" Text based color menus, radiolists & dialogs.
138			"make xconfig" X windows (Qt) based configuration tool.
139			"make gconfig" X windows (Gtk) based configuration tool.
140			"make oldconfig" Default all questions based on the contents of
141			your existing ./.config file.
142
143			NOTES on "make config":
144			- having unnecessary drivers will make the kernel bigger, and can
145			under some circumstances lead to problems: probing for a
146			nonexistent controller card may confuse your other controllers
147			- compiling the kernel with "Processor type" set higher than 386
148			will result in a kernel that does NOT work on a 386. The
149			kernel will detect this on bootup, and give up.
150			- A kernel with math-emulation compiled in will still use the
151			coprocessor if one is present: the math emulation will just
152			never get used in that case. The kernel will be slightly larger,
153			but will work on different machines regardless of whether they
154			have a math coprocessor or not.
155			- the "kernel hacking" configuration details usually result in a
156			bigger or slower kernel (or both), and can even make the kernel
157			less stable by configuring some routines to actively try to
158			break bad code to find kernel problems (kmalloc()). Thus you
159			should probably answer 'n' to the questions for
160			"development", "experimental", or "debugging" features.
161
162			- Check the top Makefile for further site-dependent configuration
163			(default SVGA mode etc).
164
165			COMPILING the kernel:
166
167			- Make sure you have gcc 2.95.3 available.
168			gcc 2.91.66 (egcs-1.1.2), and gcc 2.7.2.3 are known to miscompile
169			some parts of the kernel, and are no longer supported.
170			Also remember to upgrade your binutils package (for as/ld/nm and company)
171			if necessary. For more information, refer to Documentation/Changes.
172
173			Please note that you can still run a.out user programs with this kernel.
174
175			- Do a "make" to create a compressed kernel image. It is also
176			possible to do "make install" if you have lilo installed to suit the
177			kernel makefiles, but you may want to check your particular lilo setup first.
178
179			To do the actual install you have to be root, but none of the normal
180			build should require that. Don't take the name of root in vain.
181
182			- If you configured any of the parts of the kernel as `modules', you
183			will also have to do "make modules_install".
184
185			- Keep a backup kernel handy in case something goes wrong. This is
186			especially true for the development releases, since each new release
187			contains new code which has not been debugged. Make sure you keep a
188			backup of the modules corresponding to that kernel, as well. If you
189			are installing a new kernel with the same version number as your
190			working kernel, make a backup of your modules directory before you
191			do a "make modules_install".
192
193			- In order to boot your new kernel, you'll need to copy the kernel
194			image (e.g. .../linux/arch/i386/boot/bzImage after compilation)
195			to the place where your regular bootable kernel is found.
196
197			- Booting a kernel directly from a floppy without the assistance of a
198			bootloader such as LILO, is no longer supported.
199
200			If you boot Linux from the hard drive, chances are you use LILO which
201			uses the kernel image as specified in the file /etc/lilo.conf. The
202			kernel image file is usually /vmlinuz, /boot/vmlinuz, /bzImage or
203			/boot/bzImage. To use the new kernel, save a copy of the old image
204			and copy the new image over the old one. Then, you MUST RERUN LILO
205			to update the loading map!! If you don't, you won't be able to boot
206			the new kernel image.
207
208			Reinstalling LILO is usually a matter of running /sbin/lilo.
209			You may wish to edit /etc/lilo.conf to specify an entry for your
210			old kernel image (say, /vmlinux.old) in case the new one does not
211			work. See the LILO docs for more information.
212
213			After reinstalling LILO, you should be all set. Shutdown the system,
214			reboot, and enjoy!
215
216			If you ever need to change the default root device, video mode,
217			ramdisk size, etc. in the kernel image, use the 'rdev' program (or
218			alternatively the LILO boot options when appropriate). No need to
219			recompile the kernel to change these parameters.
220
221			- Reboot with the new kernel and enjoy.
222
223			IF SOMETHING GOES WRONG:
224
225			- If you have problems that seem to be due to kernel bugs, please check
226			the file MAINTAINERS to see if there is a particular person associated
227			with the part of the kernel that you are having trouble with. If there
228			isn't anyone listed there, then the second best thing is to mail
229			them to me (torvalds@osdl.org), and possibly to any other relevant
230			mailing-list or to the newsgroup.
231
232			- In all bug-reports, please tell what kernel you are talking about,
233			how to duplicate the problem, and what your setup is (use your common
234			sense). If the problem is new, tell me so, and if the problem is
235			old, please try to tell me when you first noticed it.
236
237			- If the bug results in a message like
238
239			unable to handle kernel paging request at address C0000010
240			Oops: 0002
241			EIP: 0010:XXXXXXXX
242			eax: xxxxxxxx ebx: xxxxxxxx ecx: xxxxxxxx edx: xxxxxxxx
243			esi: xxxxxxxx edi: xxxxxxxx ebp: xxxxxxxx
244			ds: xxxx es: xxxx fs: xxxx gs: xxxx
245			Pid: xx, process nr: xx
246			xx xx xx xx xx xx xx xx xx xx
247
248			or similar kernel debugging information on your screen or in your
249			system log, please duplicate it exactly. The dump may look
250			incomprehensible to you, but it does contain information that may
251			help debugging the problem. The text above the dump is also
252			important: it tells something about why the kernel dumped code (in
253			the above example it's due to a bad kernel pointer). More information
254			on making sense of the dump is in Documentation/oops-tracing.txt
255
256			- If you compiled the kernel with CONFIG_KALLSYMS you can send the dump
257			as is, otherwise you will have to use the "ksymoops" program to make
258			sense of the dump. This utility can be downloaded from
259			ftp://ftp.<country>.kernel.org/pub/linux/utils/kernel/ksymoops.
260			Alternately you can do the dump lookup by hand:
261
262			- In debugging dumps like the above, it helps enormously if you can
263			look up what the EIP value means. The hex value as such doesn't help
264			me or anybody else very much: it will depend on your particular
265			kernel setup. What you should do is take the hex value from the EIP
266			line (ignore the "0010:"), and look it up in the kernel namelist to
267			see which kernel function contains the offending address.
268
269			To find out the kernel function name, you'll need to find the system
270			binary associated with the kernel that exhibited the symptom. This is
271			the file 'linux/vmlinux'. To extract the namelist and match it against
272			the EIP from the kernel crash, do:
273
274			nm vmlinux \| sort \| less
275
276			This will give you a list of kernel addresses sorted in ascending
277			order, from which it is simple to find the function that contains the
278			offending address. Note that the address given by the kernel
279			debugging messages will not necessarily match exactly with the
280			function addresses (in fact, that is very unlikely), so you can't
281			just 'grep' the list: the list will, however, give you the starting
282			point of each kernel function, so by looking for the function that
283			has a starting address lower than the one you are searching for but
284			is followed by a function with a higher address you will find the one
285			you want. In fact, it may be a good idea to include a bit of
286			"context" in your problem report, giving a few lines around the
287			interesting one.
288
289			If you for some reason cannot do the above (you have a pre-compiled
290			kernel image or similar), telling me as much about your setup as
291			possible will help.
292
293			- Alternately, you can use gdb on a running kernel. (read-only; i.e. you
294			cannot change values or set break points.) To do this, first compile the
295			kernel with -g; edit arch/i386/Makefile appropriately, then do a "make
296			clean". You'll also need to enable CONFIG_PROC_FS (via "make config").
297
298			After you've rebooted with the new kernel, do "gdb vmlinux /proc/kcore".
299			You can now use all the usual gdb commands. The command to look up the
300			point where your system crashed is "l *0xXXXXXXXX". (Replace the XXXes
301			with the EIP value.)
302
303			gdb'ing a non-running kernel currently fails because gdb (wrongly)
304			disregards the starting offset for which the kernel is compiled.
305