Commit 620034c84d1d939717bdfbe02c51a3fee43541c3
Committed by
Linus Torvalds
1 parent
6fc52f81a8
Exists in
master
and in
20 other branches
[PATCH] A few small additions and corrections to README
Here's a small patch which - adds a few archs to the current list of supported platforms. - adds a few missing slashes at the end of URLs. - adds a few references to additional documentation. - adds "make config" to the list of possible configuration targets. - makes a few other minor changes. Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> [ Ben Nizette <ben.nizette@iinet.net.au> points out AVR32 arch too ] Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Showing 1 changed file with 11 additions and 6 deletions Inline Diff
README
1 | Linux kernel release 2.6.xx <http://kernel.org> | 1 | Linux kernel release 2.6.xx <http://kernel.org/> |
2 | 2 | ||
3 | These are the release notes for Linux version 2.6. Read them carefully, | 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 | 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. | 5 | kernel, and what to do if something goes wrong. |
6 | 6 | ||
7 | WHAT IS LINUX? | 7 | WHAT IS LINUX? |
8 | 8 | ||
9 | Linux is a clone of the operating system Unix, written from scratch by | 9 | Linux is a clone of the operating system Unix, written from scratch by |
10 | Linus Torvalds with assistance from a loosely-knit team of hackers across | 10 | Linus Torvalds with assistance from a loosely-knit team of hackers across |
11 | the Net. It aims towards POSIX and Single UNIX Specification compliance. | 11 | the Net. It aims towards POSIX and Single UNIX Specification compliance. |
12 | 12 | ||
13 | It has all the features you would expect in a modern fully-fledged Unix, | 13 | It has all the features you would expect in a modern fully-fledged Unix, |
14 | including true multitasking, virtual memory, shared libraries, demand | 14 | including true multitasking, virtual memory, shared libraries, demand |
15 | loading, shared copy-on-write executables, proper memory management, | 15 | loading, shared copy-on-write executables, proper memory management, |
16 | and multistack networking including IPv4 and IPv6. | 16 | and multistack networking including IPv4 and IPv6. |
17 | 17 | ||
18 | It is distributed under the GNU General Public License - see the | 18 | It is distributed under the GNU General Public License - see the |
19 | accompanying COPYING file for more details. | 19 | accompanying COPYING file for more details. |
20 | 20 | ||
21 | ON WHAT HARDWARE DOES IT RUN? | 21 | ON WHAT HARDWARE DOES IT RUN? |
22 | 22 | ||
23 | Although originally developed first for 32-bit x86-based PCs (386 or higher), | 23 | Although originally developed first for 32-bit x86-based PCs (386 or higher), |
24 | today Linux also runs on (at least) the Compaq Alpha AXP, Sun SPARC and | 24 | today Linux also runs on (at least) the Compaq Alpha AXP, Sun SPARC and |
25 | UltraSPARC, Motorola 68000, PowerPC, PowerPC64, ARM, Hitachi SuperH, | 25 | UltraSPARC, Motorola 68000, PowerPC, PowerPC64, ARM, Hitachi SuperH, Cell, |
26 | IBM S/390, MIPS, HP PA-RISC, Intel IA-64, DEC VAX, AMD x86-64, AXIS CRIS, | 26 | IBM S/390, MIPS, HP PA-RISC, Intel IA-64, DEC VAX, AMD x86-64, AXIS CRIS, |
27 | and Renesas M32R architectures. | 27 | Cris, Xtensa, AVR32 and Renesas M32R architectures. |
28 | 28 | ||
29 | Linux is easily portable to most general-purpose 32- or 64-bit architectures | 29 | Linux is easily portable to most general-purpose 32- or 64-bit architectures |
30 | as long as they have a paged memory management unit (PMMU) and a port of the | 30 | as long as they have a paged memory management unit (PMMU) and a port of the |
31 | GNU C compiler (gcc) (part of The GNU Compiler Collection, GCC). Linux has | 31 | GNU C compiler (gcc) (part of The GNU Compiler Collection, GCC). Linux has |
32 | also been ported to a number of architectures without a PMMU, although | 32 | also been ported to a number of architectures without a PMMU, although |
33 | functionality is then obviously somewhat limited. | 33 | functionality is then obviously somewhat limited. |
34 | Linux has also been ported to itself. You can now run the kernel as a | ||
35 | userspace application - this is called UserMode Linux (UML). | ||
34 | 36 | ||
35 | DOCUMENTATION: | 37 | DOCUMENTATION: |
36 | 38 | ||
37 | - There is a lot of documentation available both in electronic form on | 39 | - There is a lot of documentation available both in electronic form on |
38 | the Internet and in books, both Linux-specific and pertaining to | 40 | the Internet and in books, both Linux-specific and pertaining to |
39 | general UNIX questions. I'd recommend looking into the documentation | 41 | general UNIX questions. I'd recommend looking into the documentation |
40 | subdirectories on any Linux FTP site for the LDP (Linux Documentation | 42 | subdirectories on any Linux FTP site for the LDP (Linux Documentation |
41 | Project) books. This README is not meant to be documentation on the | 43 | Project) books. This README is not meant to be documentation on the |
42 | system: there are much better sources available. | 44 | system: there are much better sources available. |
43 | 45 | ||
44 | - There are various README files in the Documentation/ subdirectory: | 46 | - There are various README files in the Documentation/ subdirectory: |
45 | these typically contain kernel-specific installation notes for some | 47 | these typically contain kernel-specific installation notes for some |
46 | drivers for example. See Documentation/00-INDEX for a list of what | 48 | drivers for example. See Documentation/00-INDEX for a list of what |
47 | is contained in each file. Please read the Changes file, as it | 49 | is contained in each file. Please read the Changes file, as it |
48 | contains information about the problems, which may result by upgrading | 50 | contains information about the problems, which may result by upgrading |
49 | your kernel. | 51 | your kernel. |
50 | 52 | ||
51 | - The Documentation/DocBook/ subdirectory contains several guides for | 53 | - The Documentation/DocBook/ subdirectory contains several guides for |
52 | kernel developers and users. These guides can be rendered in a | 54 | kernel developers and users. These guides can be rendered in a |
53 | number of formats: PostScript (.ps), PDF, and HTML, among others. | 55 | number of formats: PostScript (.ps), PDF, and HTML, among others. |
54 | After installation, "make psdocs", "make pdfdocs", or "make htmldocs" | 56 | After installation, "make psdocs", "make pdfdocs", or "make htmldocs" |
55 | will render the documentation in the requested format. | 57 | will render the documentation in the requested format. |
56 | 58 | ||
57 | INSTALLING the kernel: | 59 | INSTALLING the kernel: |
58 | 60 | ||
59 | - If you install the full sources, put the kernel tarball in a | 61 | - If you install the full sources, put the kernel tarball in a |
60 | directory where you have permissions (eg. your home directory) and | 62 | directory where you have permissions (eg. your home directory) and |
61 | unpack it: | 63 | unpack it: |
62 | 64 | ||
63 | gzip -cd linux-2.6.XX.tar.gz | tar xvf - | 65 | gzip -cd linux-2.6.XX.tar.gz | tar xvf - |
64 | 66 | ||
65 | or | 67 | or |
66 | bzip2 -dc linux-2.6.XX.tar.bz2 | tar xvf - | 68 | bzip2 -dc linux-2.6.XX.tar.bz2 | tar xvf - |
67 | 69 | ||
68 | 70 | ||
69 | Replace "XX" with the version number of the latest kernel. | 71 | Replace "XX" with the version number of the latest kernel. |
70 | 72 | ||
71 | Do NOT use the /usr/src/linux area! This area has a (usually | 73 | Do NOT use the /usr/src/linux area! This area has a (usually |
72 | incomplete) set of kernel headers that are used by the library header | 74 | incomplete) set of kernel headers that are used by the library header |
73 | files. They should match the library, and not get messed up by | 75 | files. They should match the library, and not get messed up by |
74 | whatever the kernel-du-jour happens to be. | 76 | whatever the kernel-du-jour happens to be. |
75 | 77 | ||
76 | - You can also upgrade between 2.6.xx releases by patching. Patches are | 78 | - You can also upgrade between 2.6.xx releases by patching. Patches are |
77 | distributed in the traditional gzip and the newer bzip2 format. To | 79 | distributed in the traditional gzip and the newer bzip2 format. To |
78 | install by patching, get all the newer patch files, enter the | 80 | install by patching, get all the newer patch files, enter the |
79 | top level directory of the kernel source (linux-2.6.xx) and execute: | 81 | top level directory of the kernel source (linux-2.6.xx) and execute: |
80 | 82 | ||
81 | gzip -cd ../patch-2.6.xx.gz | patch -p1 | 83 | gzip -cd ../patch-2.6.xx.gz | patch -p1 |
82 | 84 | ||
83 | or | 85 | or |
84 | bzip2 -dc ../patch-2.6.xx.bz2 | patch -p1 | 86 | bzip2 -dc ../patch-2.6.xx.bz2 | patch -p1 |
85 | 87 | ||
86 | (repeat xx for all versions bigger than the version of your current | 88 | (repeat xx for all versions bigger than the version of your current |
87 | source tree, _in_order_) and you should be ok. You may want to remove | 89 | source tree, _in_order_) and you should be ok. You may want to remove |
88 | the backup files (xxx~ or xxx.orig), and make sure that there are no | 90 | the backup files (xxx~ or xxx.orig), and make sure that there are no |
89 | failed patches (xxx# or xxx.rej). If there are, either you or me has | 91 | failed patches (xxx# or xxx.rej). If there are, either you or me has |
90 | made a mistake. | 92 | made a mistake. |
91 | 93 | ||
92 | Unlike patches for the 2.6.x kernels, patches for the 2.6.x.y kernels | 94 | Unlike patches for the 2.6.x kernels, patches for the 2.6.x.y kernels |
93 | (also known as the -stable kernels) are not incremental but instead apply | 95 | (also known as the -stable kernels) are not incremental but instead apply |
94 | directly to the base 2.6.x kernel. Please read | 96 | directly to the base 2.6.x kernel. Please read |
95 | Documentation/applying-patches.txt for more information. | 97 | Documentation/applying-patches.txt for more information. |
96 | 98 | ||
97 | Alternatively, the script patch-kernel can be used to automate this | 99 | Alternatively, the script patch-kernel can be used to automate this |
98 | process. It determines the current kernel version and applies any | 100 | process. It determines the current kernel version and applies any |
99 | patches found. | 101 | patches found. |
100 | 102 | ||
101 | linux/scripts/patch-kernel linux | 103 | linux/scripts/patch-kernel linux |
102 | 104 | ||
103 | The first argument in the command above is the location of the | 105 | The first argument in the command above is the location of the |
104 | kernel source. Patches are applied from the current directory, but | 106 | kernel source. Patches are applied from the current directory, but |
105 | an alternative directory can be specified as the second argument. | 107 | an alternative directory can be specified as the second argument. |
106 | 108 | ||
107 | - If you are upgrading between releases using the stable series patches | 109 | - If you are upgrading between releases using the stable series patches |
108 | (for example, patch-2.6.xx.y), note that these "dot-releases" are | 110 | (for example, patch-2.6.xx.y), note that these "dot-releases" are |
109 | not incremental and must be applied to the 2.6.xx base tree. For | 111 | not incremental and must be applied to the 2.6.xx base tree. For |
110 | example, if your base kernel is 2.6.12 and you want to apply the | 112 | example, if your base kernel is 2.6.12 and you want to apply the |
111 | 2.6.12.3 patch, you do not and indeed must not first apply the | 113 | 2.6.12.3 patch, you do not and indeed must not first apply the |
112 | 2.6.12.1 and 2.6.12.2 patches. Similarly, if you are running kernel | 114 | 2.6.12.1 and 2.6.12.2 patches. Similarly, if you are running kernel |
113 | version 2.6.12.2 and want to jump to 2.6.12.3, you must first | 115 | version 2.6.12.2 and want to jump to 2.6.12.3, you must first |
114 | reverse the 2.6.12.2 patch (that is, patch -R) _before_ applying | 116 | reverse the 2.6.12.2 patch (that is, patch -R) _before_ applying |
115 | the 2.6.12.3 patch. | 117 | the 2.6.12.3 patch. |
118 | You can read more on this in Documentation/applying-patches.txt | ||
116 | 119 | ||
117 | - Make sure you have no stale .o files and dependencies lying around: | 120 | - Make sure you have no stale .o files and dependencies lying around: |
118 | 121 | ||
119 | cd linux | 122 | cd linux |
120 | make mrproper | 123 | make mrproper |
121 | 124 | ||
122 | You should now have the sources correctly installed. | 125 | You should now have the sources correctly installed. |
123 | 126 | ||
124 | SOFTWARE REQUIREMENTS | 127 | SOFTWARE REQUIREMENTS |
125 | 128 | ||
126 | Compiling and running the 2.6.xx kernels requires up-to-date | 129 | Compiling and running the 2.6.xx kernels requires up-to-date |
127 | versions of various software packages. Consult | 130 | versions of various software packages. Consult |
128 | Documentation/Changes for the minimum version numbers required | 131 | Documentation/Changes for the minimum version numbers required |
129 | and how to get updates for these packages. Beware that using | 132 | and how to get updates for these packages. Beware that using |
130 | excessively old versions of these packages can cause indirect | 133 | excessively old versions of these packages can cause indirect |
131 | errors that are very difficult to track down, so don't assume that | 134 | errors that are very difficult to track down, so don't assume that |
132 | you can just update packages when obvious problems arise during | 135 | you can just update packages when obvious problems arise during |
133 | build or operation. | 136 | build or operation. |
134 | 137 | ||
135 | BUILD directory for the kernel: | 138 | BUILD directory for the kernel: |
136 | 139 | ||
137 | When compiling the kernel all output files will per default be | 140 | When compiling the kernel all output files will per default be |
138 | stored together with the kernel source code. | 141 | stored together with the kernel source code. |
139 | Using the option "make O=output/dir" allow you to specify an alternate | 142 | Using the option "make O=output/dir" allow you to specify an alternate |
140 | place for the output files (including .config). | 143 | place for the output files (including .config). |
141 | Example: | 144 | Example: |
142 | kernel source code: /usr/src/linux-2.6.N | 145 | kernel source code: /usr/src/linux-2.6.N |
143 | build directory: /home/name/build/kernel | 146 | build directory: /home/name/build/kernel |
144 | 147 | ||
145 | To configure and build the kernel use: | 148 | To configure and build the kernel use: |
146 | cd /usr/src/linux-2.6.N | 149 | cd /usr/src/linux-2.6.N |
147 | make O=/home/name/build/kernel menuconfig | 150 | make O=/home/name/build/kernel menuconfig |
148 | make O=/home/name/build/kernel | 151 | make O=/home/name/build/kernel |
149 | sudo make O=/home/name/build/kernel modules_install install | 152 | sudo make O=/home/name/build/kernel modules_install install |
150 | 153 | ||
151 | Please note: If the 'O=output/dir' option is used then it must be | 154 | Please note: If the 'O=output/dir' option is used then it must be |
152 | used for all invocations of make. | 155 | used for all invocations of make. |
153 | 156 | ||
154 | CONFIGURING the kernel: | 157 | CONFIGURING the kernel: |
155 | 158 | ||
156 | Do not skip this step even if you are only upgrading one minor | 159 | Do not skip this step even if you are only upgrading one minor |
157 | version. New configuration options are added in each release, and | 160 | version. New configuration options are added in each release, and |
158 | odd problems will turn up if the configuration files are not set up | 161 | odd problems will turn up if the configuration files are not set up |
159 | as expected. If you want to carry your existing configuration to a | 162 | as expected. If you want to carry your existing configuration to a |
160 | new version with minimal work, use "make oldconfig", which will | 163 | new version with minimal work, use "make oldconfig", which will |
161 | only ask you for the answers to new questions. | 164 | only ask you for the answers to new questions. |
162 | 165 | ||
163 | - Alternate configuration commands are: | 166 | - Alternate configuration commands are: |
167 | "make config" Plain text interface. | ||
164 | "make menuconfig" Text based color menus, radiolists & dialogs. | 168 | "make menuconfig" Text based color menus, radiolists & dialogs. |
165 | "make xconfig" X windows (Qt) based configuration tool. | 169 | "make xconfig" X windows (Qt) based configuration tool. |
166 | "make gconfig" X windows (Gtk) based configuration tool. | 170 | "make gconfig" X windows (Gtk) based configuration tool. |
167 | "make oldconfig" Default all questions based on the contents of | 171 | "make oldconfig" Default all questions based on the contents of |
168 | your existing ./.config file and asking about | 172 | your existing ./.config file and asking about |
169 | new config symbols. | 173 | new config symbols. |
170 | "make silentoldconfig" | 174 | "make silentoldconfig" |
171 | Like above, but avoids cluttering the screen | 175 | Like above, but avoids cluttering the screen |
172 | with questions already answered. | 176 | with questions already answered. |
173 | "make defconfig" Create a ./.config file by using the default | 177 | "make defconfig" Create a ./.config file by using the default |
174 | symbol values from arch/$ARCH/defconfig. | 178 | symbol values from arch/$ARCH/defconfig. |
175 | "make allyesconfig" | 179 | "make allyesconfig" |
176 | Create a ./.config file by setting symbol | 180 | Create a ./.config file by setting symbol |
177 | values to 'y' as much as possible. | 181 | values to 'y' as much as possible. |
178 | "make allmodconfig" | 182 | "make allmodconfig" |
179 | Create a ./.config file by setting symbol | 183 | Create a ./.config file by setting symbol |
180 | values to 'm' as much as possible. | 184 | values to 'm' as much as possible. |
181 | "make allnoconfig" Create a ./.config file by setting symbol | 185 | "make allnoconfig" Create a ./.config file by setting symbol |
182 | values to 'n' as much as possible. | 186 | values to 'n' as much as possible. |
183 | "make randconfig" Create a ./.config file by setting symbol | 187 | "make randconfig" Create a ./.config file by setting symbol |
184 | values to random values. | 188 | values to random values. |
185 | 189 | ||
186 | The allyesconfig/allmodconfig/allnoconfig/randconfig variants can | 190 | The allyesconfig/allmodconfig/allnoconfig/randconfig variants can |
187 | also use the environment variable KCONFIG_ALLCONFIG to specify a | 191 | also use the environment variable KCONFIG_ALLCONFIG to specify a |
188 | filename that contains config options that the user requires to be | 192 | filename that contains config options that the user requires to be |
189 | set to a specific value. If KCONFIG_ALLCONFIG=filename is not used, | 193 | set to a specific value. If KCONFIG_ALLCONFIG=filename is not used, |
190 | "make *config" checks for a file named "all{yes/mod/no/random}.config" | 194 | "make *config" checks for a file named "all{yes/mod/no/random}.config" |
191 | for symbol values that are to be forced. If this file is not found, | 195 | for symbol values that are to be forced. If this file is not found, |
192 | it checks for a file named "all.config" to contain forced values. | 196 | it checks for a file named "all.config" to contain forced values. |
193 | 197 | ||
194 | NOTES on "make config": | 198 | NOTES on "make config": |
195 | - having unnecessary drivers will make the kernel bigger, and can | 199 | - having unnecessary drivers will make the kernel bigger, and can |
196 | under some circumstances lead to problems: probing for a | 200 | under some circumstances lead to problems: probing for a |
197 | nonexistent controller card may confuse your other controllers | 201 | nonexistent controller card may confuse your other controllers |
198 | - compiling the kernel with "Processor type" set higher than 386 | 202 | - compiling the kernel with "Processor type" set higher than 386 |
199 | will result in a kernel that does NOT work on a 386. The | 203 | will result in a kernel that does NOT work on a 386. The |
200 | kernel will detect this on bootup, and give up. | 204 | kernel will detect this on bootup, and give up. |
201 | - A kernel with math-emulation compiled in will still use the | 205 | - A kernel with math-emulation compiled in will still use the |
202 | coprocessor if one is present: the math emulation will just | 206 | coprocessor if one is present: the math emulation will just |
203 | never get used in that case. The kernel will be slightly larger, | 207 | never get used in that case. The kernel will be slightly larger, |
204 | but will work on different machines regardless of whether they | 208 | but will work on different machines regardless of whether they |
205 | have a math coprocessor or not. | 209 | have a math coprocessor or not. |
206 | - the "kernel hacking" configuration details usually result in a | 210 | - the "kernel hacking" configuration details usually result in a |
207 | bigger or slower kernel (or both), and can even make the kernel | 211 | bigger or slower kernel (or both), and can even make the kernel |
208 | less stable by configuring some routines to actively try to | 212 | less stable by configuring some routines to actively try to |
209 | break bad code to find kernel problems (kmalloc()). Thus you | 213 | break bad code to find kernel problems (kmalloc()). Thus you |
210 | should probably answer 'n' to the questions for | 214 | should probably answer 'n' to the questions for |
211 | "development", "experimental", or "debugging" features. | 215 | "development", "experimental", or "debugging" features. |
212 | 216 | ||
213 | COMPILING the kernel: | 217 | COMPILING the kernel: |
214 | 218 | ||
215 | - Make sure you have at least gcc 3.2 available. | 219 | - Make sure you have at least gcc 3.2 available. |
216 | For more information, refer to Documentation/Changes. | 220 | For more information, refer to Documentation/Changes. |
217 | 221 | ||
218 | Please note that you can still run a.out user programs with this kernel. | 222 | Please note that you can still run a.out user programs with this kernel. |
219 | 223 | ||
220 | - Do a "make" to create a compressed kernel image. It is also | 224 | - Do a "make" to create a compressed kernel image. It is also |
221 | possible to do "make install" if you have lilo installed to suit the | 225 | possible to do "make install" if you have lilo installed to suit the |
222 | kernel makefiles, but you may want to check your particular lilo setup first. | 226 | kernel makefiles, but you may want to check your particular lilo setup first. |
223 | 227 | ||
224 | To do the actual install you have to be root, but none of the normal | 228 | To do the actual install you have to be root, but none of the normal |
225 | build should require that. Don't take the name of root in vain. | 229 | build should require that. Don't take the name of root in vain. |
226 | 230 | ||
227 | - If you configured any of the parts of the kernel as `modules', you | 231 | - If you configured any of the parts of the kernel as `modules', you |
228 | will also have to do "make modules_install". | 232 | will also have to do "make modules_install". |
229 | 233 | ||
230 | - Keep a backup kernel handy in case something goes wrong. This is | 234 | - Keep a backup kernel handy in case something goes wrong. This is |
231 | especially true for the development releases, since each new release | 235 | especially true for the development releases, since each new release |
232 | contains new code which has not been debugged. Make sure you keep a | 236 | contains new code which has not been debugged. Make sure you keep a |
233 | backup of the modules corresponding to that kernel, as well. If you | 237 | backup of the modules corresponding to that kernel, as well. If you |
234 | are installing a new kernel with the same version number as your | 238 | are installing a new kernel with the same version number as your |
235 | working kernel, make a backup of your modules directory before you | 239 | working kernel, make a backup of your modules directory before you |
236 | do a "make modules_install". | 240 | do a "make modules_install". |
237 | Alternatively, before compiling, use the kernel config option | 241 | Alternatively, before compiling, use the kernel config option |
238 | "LOCALVERSION" to append a unique suffix to the regular kernel version. | 242 | "LOCALVERSION" to append a unique suffix to the regular kernel version. |
239 | LOCALVERSION can be set in the "General Setup" menu. | 243 | LOCALVERSION can be set in the "General Setup" menu. |
240 | 244 | ||
241 | - In order to boot your new kernel, you'll need to copy the kernel | 245 | - In order to boot your new kernel, you'll need to copy the kernel |
242 | image (e.g. .../linux/arch/i386/boot/bzImage after compilation) | 246 | image (e.g. .../linux/arch/i386/boot/bzImage after compilation) |
243 | to the place where your regular bootable kernel is found. | 247 | to the place where your regular bootable kernel is found. |
244 | 248 | ||
245 | - Booting a kernel directly from a floppy without the assistance of a | 249 | - Booting a kernel directly from a floppy without the assistance of a |
246 | bootloader such as LILO, is no longer supported. | 250 | bootloader such as LILO, is no longer supported. |
247 | 251 | ||
248 | If you boot Linux from the hard drive, chances are you use LILO which | 252 | If you boot Linux from the hard drive, chances are you use LILO which |
249 | uses the kernel image as specified in the file /etc/lilo.conf. The | 253 | uses the kernel image as specified in the file /etc/lilo.conf. The |
250 | kernel image file is usually /vmlinuz, /boot/vmlinuz, /bzImage or | 254 | kernel image file is usually /vmlinuz, /boot/vmlinuz, /bzImage or |
251 | /boot/bzImage. To use the new kernel, save a copy of the old image | 255 | /boot/bzImage. To use the new kernel, save a copy of the old image |
252 | and copy the new image over the old one. Then, you MUST RERUN LILO | 256 | and copy the new image over the old one. Then, you MUST RERUN LILO |
253 | to update the loading map!! If you don't, you won't be able to boot | 257 | to update the loading map!! If you don't, you won't be able to boot |
254 | the new kernel image. | 258 | the new kernel image. |
255 | 259 | ||
256 | Reinstalling LILO is usually a matter of running /sbin/lilo. | 260 | Reinstalling LILO is usually a matter of running /sbin/lilo. |
257 | You may wish to edit /etc/lilo.conf to specify an entry for your | 261 | You may wish to edit /etc/lilo.conf to specify an entry for your |
258 | old kernel image (say, /vmlinux.old) in case the new one does not | 262 | old kernel image (say, /vmlinux.old) in case the new one does not |
259 | work. See the LILO docs for more information. | 263 | work. See the LILO docs for more information. |
260 | 264 | ||
261 | After reinstalling LILO, you should be all set. Shutdown the system, | 265 | After reinstalling LILO, you should be all set. Shutdown the system, |
262 | reboot, and enjoy! | 266 | reboot, and enjoy! |
263 | 267 | ||
264 | If you ever need to change the default root device, video mode, | 268 | If you ever need to change the default root device, video mode, |
265 | ramdisk size, etc. in the kernel image, use the 'rdev' program (or | 269 | ramdisk size, etc. in the kernel image, use the 'rdev' program (or |
266 | alternatively the LILO boot options when appropriate). No need to | 270 | alternatively the LILO boot options when appropriate). No need to |
267 | recompile the kernel to change these parameters. | 271 | recompile the kernel to change these parameters. |
268 | 272 | ||
269 | - Reboot with the new kernel and enjoy. | 273 | - Reboot with the new kernel and enjoy. |
270 | 274 | ||
271 | IF SOMETHING GOES WRONG: | 275 | IF SOMETHING GOES WRONG: |
272 | 276 | ||
273 | - If you have problems that seem to be due to kernel bugs, please check | 277 | - If you have problems that seem to be due to kernel bugs, please check |
274 | the file MAINTAINERS to see if there is a particular person associated | 278 | the file MAINTAINERS to see if there is a particular person associated |
275 | with the part of the kernel that you are having trouble with. If there | 279 | with the part of the kernel that you are having trouble with. If there |
276 | isn't anyone listed there, then the second best thing is to mail | 280 | isn't anyone listed there, then the second best thing is to mail |
277 | them to me (torvalds@osdl.org), and possibly to any other relevant | 281 | them to me (torvalds@osdl.org), and possibly to any other relevant |
278 | mailing-list or to the newsgroup. | 282 | mailing-list or to the newsgroup. |
279 | 283 | ||
280 | - In all bug-reports, *please* tell what kernel you are talking about, | 284 | - In all bug-reports, *please* tell what kernel you are talking about, |
281 | how to duplicate the problem, and what your setup is (use your common | 285 | how to duplicate the problem, and what your setup is (use your common |
282 | sense). If the problem is new, tell me so, and if the problem is | 286 | sense). If the problem is new, tell me so, and if the problem is |
283 | old, please try to tell me when you first noticed it. | 287 | old, please try to tell me when you first noticed it. |
284 | 288 | ||
285 | - If the bug results in a message like | 289 | - If the bug results in a message like |
286 | 290 | ||
287 | unable to handle kernel paging request at address C0000010 | 291 | unable to handle kernel paging request at address C0000010 |
288 | Oops: 0002 | 292 | Oops: 0002 |
289 | EIP: 0010:XXXXXXXX | 293 | EIP: 0010:XXXXXXXX |
290 | eax: xxxxxxxx ebx: xxxxxxxx ecx: xxxxxxxx edx: xxxxxxxx | 294 | eax: xxxxxxxx ebx: xxxxxxxx ecx: xxxxxxxx edx: xxxxxxxx |
291 | esi: xxxxxxxx edi: xxxxxxxx ebp: xxxxxxxx | 295 | esi: xxxxxxxx edi: xxxxxxxx ebp: xxxxxxxx |
292 | ds: xxxx es: xxxx fs: xxxx gs: xxxx | 296 | ds: xxxx es: xxxx fs: xxxx gs: xxxx |
293 | Pid: xx, process nr: xx | 297 | Pid: xx, process nr: xx |
294 | xx xx xx xx xx xx xx xx xx xx | 298 | xx xx xx xx xx xx xx xx xx xx |
295 | 299 | ||
296 | or similar kernel debugging information on your screen or in your | 300 | or similar kernel debugging information on your screen or in your |
297 | system log, please duplicate it *exactly*. The dump may look | 301 | system log, please duplicate it *exactly*. The dump may look |
298 | incomprehensible to you, but it does contain information that may | 302 | incomprehensible to you, but it does contain information that may |
299 | help debugging the problem. The text above the dump is also | 303 | help debugging the problem. The text above the dump is also |
300 | important: it tells something about why the kernel dumped code (in | 304 | important: it tells something about why the kernel dumped code (in |
301 | the above example it's due to a bad kernel pointer). More information | 305 | the above example it's due to a bad kernel pointer). More information |
302 | on making sense of the dump is in Documentation/oops-tracing.txt | 306 | on making sense of the dump is in Documentation/oops-tracing.txt |
303 | 307 | ||
304 | - If you compiled the kernel with CONFIG_KALLSYMS you can send the dump | 308 | - If you compiled the kernel with CONFIG_KALLSYMS you can send the dump |
305 | as is, otherwise you will have to use the "ksymoops" program to make | 309 | as is, otherwise you will have to use the "ksymoops" program to make |
306 | sense of the dump. This utility can be downloaded from | 310 | sense of the dump (but compiling with CONFIG_KALLSYMS is usually preferred). |
307 | ftp://ftp.<country>.kernel.org/pub/linux/utils/kernel/ksymoops. | 311 | This utility can be downloaded from |
312 | ftp://ftp.<country>.kernel.org/pub/linux/utils/kernel/ksymoops/ . | ||
308 | Alternately you can do the dump lookup by hand: | 313 | Alternately you can do the dump lookup by hand: |
309 | 314 | ||
310 | - In debugging dumps like the above, it helps enormously if you can | 315 | - In debugging dumps like the above, it helps enormously if you can |
311 | look up what the EIP value means. The hex value as such doesn't help | 316 | look up what the EIP value means. The hex value as such doesn't help |
312 | me or anybody else very much: it will depend on your particular | 317 | me or anybody else very much: it will depend on your particular |
313 | kernel setup. What you should do is take the hex value from the EIP | 318 | kernel setup. What you should do is take the hex value from the EIP |
314 | line (ignore the "0010:"), and look it up in the kernel namelist to | 319 | line (ignore the "0010:"), and look it up in the kernel namelist to |
315 | see which kernel function contains the offending address. | 320 | see which kernel function contains the offending address. |
316 | 321 | ||
317 | To find out the kernel function name, you'll need to find the system | 322 | To find out the kernel function name, you'll need to find the system |
318 | binary associated with the kernel that exhibited the symptom. This is | 323 | binary associated with the kernel that exhibited the symptom. This is |
319 | the file 'linux/vmlinux'. To extract the namelist and match it against | 324 | the file 'linux/vmlinux'. To extract the namelist and match it against |
320 | the EIP from the kernel crash, do: | 325 | the EIP from the kernel crash, do: |
321 | 326 | ||
322 | nm vmlinux | sort | less | 327 | nm vmlinux | sort | less |
323 | 328 | ||
324 | This will give you a list of kernel addresses sorted in ascending | 329 | This will give you a list of kernel addresses sorted in ascending |
325 | order, from which it is simple to find the function that contains the | 330 | order, from which it is simple to find the function that contains the |
326 | offending address. Note that the address given by the kernel | 331 | offending address. Note that the address given by the kernel |
327 | debugging messages will not necessarily match exactly with the | 332 | debugging messages will not necessarily match exactly with the |
328 | function addresses (in fact, that is very unlikely), so you can't | 333 | function addresses (in fact, that is very unlikely), so you can't |
329 | just 'grep' the list: the list will, however, give you the starting | 334 | just 'grep' the list: the list will, however, give you the starting |
330 | point of each kernel function, so by looking for the function that | 335 | point of each kernel function, so by looking for the function that |
331 | has a starting address lower than the one you are searching for but | 336 | has a starting address lower than the one you are searching for but |
332 | is followed by a function with a higher address you will find the one | 337 | is followed by a function with a higher address you will find the one |
333 | you want. In fact, it may be a good idea to include a bit of | 338 | you want. In fact, it may be a good idea to include a bit of |
334 | "context" in your problem report, giving a few lines around the | 339 | "context" in your problem report, giving a few lines around the |
335 | interesting one. | 340 | interesting one. |
336 | 341 | ||
337 | If you for some reason cannot do the above (you have a pre-compiled | 342 | If you for some reason cannot do the above (you have a pre-compiled |
338 | kernel image or similar), telling me as much about your setup as | 343 | kernel image or similar), telling me as much about your setup as |
339 | possible will help. | 344 | possible will help. Please read the REPORTING-BUGS document for details. |
340 | 345 | ||
341 | - Alternately, you can use gdb on a running kernel. (read-only; i.e. you | 346 | - Alternately, you can use gdb on a running kernel. (read-only; i.e. you |
342 | cannot change values or set break points.) To do this, first compile the | 347 | cannot change values or set break points.) To do this, first compile the |
343 | kernel with -g; edit arch/i386/Makefile appropriately, then do a "make | 348 | kernel with -g; edit arch/i386/Makefile appropriately, then do a "make |
344 | clean". You'll also need to enable CONFIG_PROC_FS (via "make config"). | 349 | clean". You'll also need to enable CONFIG_PROC_FS (via "make config"). |
345 | 350 | ||
346 | After you've rebooted with the new kernel, do "gdb vmlinux /proc/kcore". | 351 | After you've rebooted with the new kernel, do "gdb vmlinux /proc/kcore". |
347 | You can now use all the usual gdb commands. The command to look up the | 352 | You can now use all the usual gdb commands. The command to look up the |
348 | point where your system crashed is "l *0xXXXXXXXX". (Replace the XXXes | 353 | point where your system crashed is "l *0xXXXXXXXX". (Replace the XXXes |
349 | with the EIP value.) | 354 | with the EIP value.) |
350 | 355 | ||
351 | gdb'ing a non-running kernel currently fails because gdb (wrongly) | 356 | gdb'ing a non-running kernel currently fails because gdb (wrongly) |
352 | disregards the starting offset for which the kernel is compiled. | 357 | disregards the starting offset for which the kernel is compiled. |
353 | 358 | ||
354 | 359 |