Commit 6ad44229ec85b3938a313a325f0449e23eac8aac
Committed by
Linus Torvalds
1 parent
3f39894d1b
Exists in
master
and in
20 other branches
[PATCH] README: add info about -stable to README and point at applying-patches.txt
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Showing 1 changed file with 5 additions and 0 deletions Inline Diff
README
1 | Linux kernel release 2.6.xx | 1 | Linux kernel release 2.6.xx |
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 Unix clone written from scratch by Linus Torvalds with | 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. | 10 | assistance from a loosely-knit team of hackers across the Net. |
11 | It aims towards POSIX compliance. | 11 | It aims towards POSIX compliance. |
12 | 12 | ||
13 | It has all the features you would expect in a modern fully-fledged | 13 | It has all the features you would expect in a modern fully-fledged |
14 | Unix, including true multitasking, virtual memory, shared libraries, | 14 | Unix, including true multitasking, virtual memory, shared libraries, |
15 | demand loading, shared copy-on-write executables, proper memory | 15 | demand loading, shared copy-on-write executables, proper memory |
16 | management and TCP/IP networking. | 16 | management and TCP/IP networking. |
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 | Linux was first developed for 386/486-based PCs. These days it also | 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 | 24 | runs on ARMs, DEC Alphas, SUN Sparcs, M68000 machines (like Atari and |
25 | Amiga), MIPS and PowerPC, and others. | 25 | Amiga), MIPS and PowerPC, and others. |
26 | 26 | ||
27 | DOCUMENTATION: | 27 | DOCUMENTATION: |
28 | 28 | ||
29 | - There is a lot of documentation available both in electronic form on | 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 | 30 | the Internet and in books, both Linux-specific and pertaining to |
31 | general UNIX questions. I'd recommend looking into the documentation | 31 | general UNIX questions. I'd recommend looking into the documentation |
32 | subdirectories on any Linux FTP site for the LDP (Linux 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 | 33 | Project) books. This README is not meant to be documentation on the |
34 | system: there are much better sources available. | 34 | system: there are much better sources available. |
35 | 35 | ||
36 | - There are various README files in the Documentation/ subdirectory: | 36 | - There are various README files in the Documentation/ subdirectory: |
37 | these typically contain kernel-specific installation notes for some | 37 | these typically contain kernel-specific installation notes for some |
38 | drivers for example. See Documentation/00-INDEX for a list of what | 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 | 39 | is contained in each file. Please read the Changes file, as it |
40 | contains information about the problems, which may result by upgrading | 40 | contains information about the problems, which may result by upgrading |
41 | your kernel. | 41 | your kernel. |
42 | 42 | ||
43 | - The Documentation/DocBook/ subdirectory contains several guides for | 43 | - The Documentation/DocBook/ subdirectory contains several guides for |
44 | kernel developers and users. These guides can be rendered in a | 44 | kernel developers and users. These guides can be rendered in a |
45 | number of formats: PostScript (.ps), PDF, and HTML, among others. | 45 | number of formats: PostScript (.ps), PDF, and HTML, among others. |
46 | After installation, "make psdocs", "make pdfdocs", or "make htmldocs" | 46 | After installation, "make psdocs", "make pdfdocs", or "make htmldocs" |
47 | will render the documentation in the requested format. | 47 | will render the documentation in the requested format. |
48 | 48 | ||
49 | INSTALLING the kernel: | 49 | INSTALLING the kernel: |
50 | 50 | ||
51 | - If you install the full sources, put the kernel tarball in a | 51 | - If you install the full sources, put the kernel tarball in a |
52 | directory where you have permissions (eg. your home directory) and | 52 | directory where you have permissions (eg. your home directory) and |
53 | unpack it: | 53 | unpack it: |
54 | 54 | ||
55 | gzip -cd linux-2.6.XX.tar.gz | tar xvf - | 55 | gzip -cd linux-2.6.XX.tar.gz | tar xvf - |
56 | 56 | ||
57 | or | 57 | or |
58 | bzip2 -dc linux-2.6.XX.tar.bz2 | tar xvf - | 58 | bzip2 -dc linux-2.6.XX.tar.bz2 | tar xvf - |
59 | 59 | ||
60 | 60 | ||
61 | Replace "XX" with the version number of the latest kernel. | 61 | Replace "XX" with the version number of the latest kernel. |
62 | 62 | ||
63 | Do NOT use the /usr/src/linux area! This area has a (usually | 63 | Do NOT use the /usr/src/linux area! This area has a (usually |
64 | incomplete) set of kernel headers that are used by the library header | 64 | incomplete) set of kernel headers that are used by the library header |
65 | files. They should match the library, and not get messed up by | 65 | files. They should match the library, and not get messed up by |
66 | whatever the kernel-du-jour happens to be. | 66 | whatever the kernel-du-jour happens to be. |
67 | 67 | ||
68 | - You can also upgrade between 2.6.xx releases by patching. Patches are | 68 | - You can also upgrade between 2.6.xx releases by patching. Patches are |
69 | distributed in the traditional gzip and the new bzip2 format. To | 69 | distributed in the traditional gzip and the new bzip2 format. To |
70 | install by patching, get all the newer patch files, enter the | 70 | install by patching, get all the newer patch files, enter the |
71 | top level directory of the kernel source (linux-2.6.xx) and execute: | 71 | top level directory of the kernel source (linux-2.6.xx) and execute: |
72 | 72 | ||
73 | gzip -cd ../patch-2.6.xx.gz | patch -p1 | 73 | gzip -cd ../patch-2.6.xx.gz | patch -p1 |
74 | 74 | ||
75 | or | 75 | or |
76 | bzip2 -dc ../patch-2.6.xx.bz2 | patch -p1 | 76 | bzip2 -dc ../patch-2.6.xx.bz2 | patch -p1 |
77 | 77 | ||
78 | (repeat xx for all versions bigger than the version of your current | 78 | (repeat xx for all versions bigger than the version of your current |
79 | source tree, _in_order_) and you should be ok. You may want to remove | 79 | source tree, _in_order_) and you should be ok. You may want to remove |
80 | the backup files (xxx~ or xxx.orig), and make sure that there are no | 80 | the backup files (xxx~ or xxx.orig), and make sure that there are no |
81 | failed patches (xxx# or xxx.rej). If there are, either you or me has | 81 | failed patches (xxx# or xxx.rej). If there are, either you or me has |
82 | made a mistake. | 82 | made a mistake. |
83 | 83 | ||
84 | Unlike patches for the 2.6.x kernels, patches for the 2.6.x.y kernels | ||
85 | (also known as the -stable kernels) are not incremental but instead apply | ||
86 | directly to the base 2.6.x kernel. Please read | ||
87 | Documentation/applying-patches.txt for more information. | ||
88 | |||
84 | Alternatively, the script patch-kernel can be used to automate this | 89 | Alternatively, the script patch-kernel can be used to automate this |
85 | process. It determines the current kernel version and applies any | 90 | process. It determines the current kernel version and applies any |
86 | patches found. | 91 | patches found. |
87 | 92 | ||
88 | linux/scripts/patch-kernel linux | 93 | linux/scripts/patch-kernel linux |
89 | 94 | ||
90 | The first argument in the command above is the location of the | 95 | The first argument in the command above is the location of the |
91 | kernel source. Patches are applied from the current directory, but | 96 | kernel source. Patches are applied from the current directory, but |
92 | an alternative directory can be specified as the second argument. | 97 | an alternative directory can be specified as the second argument. |
93 | 98 | ||
94 | - If you are upgrading between releases using the stable series patches | 99 | - If you are upgrading between releases using the stable series patches |
95 | (for example, patch-2.6.xx.y), note that these "dot-releases" are | 100 | (for example, patch-2.6.xx.y), note that these "dot-releases" are |
96 | not incremental and must be applied to the 2.6.xx base tree. For | 101 | not incremental and must be applied to the 2.6.xx base tree. For |
97 | example, if your base kernel is 2.6.12 and you want to apply the | 102 | example, if your base kernel is 2.6.12 and you want to apply the |
98 | 2.6.12.3 patch, you do not and indeed must not first apply the | 103 | 2.6.12.3 patch, you do not and indeed must not first apply the |
99 | 2.6.12.1 and 2.6.12.2 patches. Similarly, if you are running kernel | 104 | 2.6.12.1 and 2.6.12.2 patches. Similarly, if you are running kernel |
100 | version 2.6.12.2 and want to jump to 2.6.12.3, you must first | 105 | version 2.6.12.2 and want to jump to 2.6.12.3, you must first |
101 | reverse the 2.6.12.2 patch (that is, patch -R) _before_ applying | 106 | reverse the 2.6.12.2 patch (that is, patch -R) _before_ applying |
102 | the 2.6.12.3 patch. | 107 | the 2.6.12.3 patch. |
103 | 108 | ||
104 | - Make sure you have no stale .o files and dependencies lying around: | 109 | - Make sure you have no stale .o files and dependencies lying around: |
105 | 110 | ||
106 | cd linux | 111 | cd linux |
107 | make mrproper | 112 | make mrproper |
108 | 113 | ||
109 | You should now have the sources correctly installed. | 114 | You should now have the sources correctly installed. |
110 | 115 | ||
111 | SOFTWARE REQUIREMENTS | 116 | SOFTWARE REQUIREMENTS |
112 | 117 | ||
113 | Compiling and running the 2.6.xx kernels requires up-to-date | 118 | Compiling and running the 2.6.xx kernels requires up-to-date |
114 | versions of various software packages. Consult | 119 | versions of various software packages. Consult |
115 | Documentation/Changes for the minimum version numbers required | 120 | Documentation/Changes for the minimum version numbers required |
116 | and how to get updates for these packages. Beware that using | 121 | and how to get updates for these packages. Beware that using |
117 | excessively old versions of these packages can cause indirect | 122 | excessively old versions of these packages can cause indirect |
118 | errors that are very difficult to track down, so don't assume that | 123 | errors that are very difficult to track down, so don't assume that |
119 | you can just update packages when obvious problems arise during | 124 | you can just update packages when obvious problems arise during |
120 | build or operation. | 125 | build or operation. |
121 | 126 | ||
122 | BUILD directory for the kernel: | 127 | BUILD directory for the kernel: |
123 | 128 | ||
124 | When compiling the kernel all output files will per default be | 129 | When compiling the kernel all output files will per default be |
125 | stored together with the kernel source code. | 130 | stored together with the kernel source code. |
126 | Using the option "make O=output/dir" allow you to specify an alternate | 131 | Using the option "make O=output/dir" allow you to specify an alternate |
127 | place for the output files (including .config). | 132 | place for the output files (including .config). |
128 | Example: | 133 | Example: |
129 | kernel source code: /usr/src/linux-2.6.N | 134 | kernel source code: /usr/src/linux-2.6.N |
130 | build directory: /home/name/build/kernel | 135 | build directory: /home/name/build/kernel |
131 | 136 | ||
132 | To configure and build the kernel use: | 137 | To configure and build the kernel use: |
133 | cd /usr/src/linux-2.6.N | 138 | cd /usr/src/linux-2.6.N |
134 | make O=/home/name/build/kernel menuconfig | 139 | make O=/home/name/build/kernel menuconfig |
135 | make O=/home/name/build/kernel | 140 | make O=/home/name/build/kernel |
136 | sudo make O=/home/name/build/kernel modules_install install | 141 | sudo make O=/home/name/build/kernel modules_install install |
137 | 142 | ||
138 | Please note: If the 'O=output/dir' option is used then it must be | 143 | Please note: If the 'O=output/dir' option is used then it must be |
139 | used for all invocations of make. | 144 | used for all invocations of make. |
140 | 145 | ||
141 | CONFIGURING the kernel: | 146 | CONFIGURING the kernel: |
142 | 147 | ||
143 | Do not skip this step even if you are only upgrading one minor | 148 | Do not skip this step even if you are only upgrading one minor |
144 | version. New configuration options are added in each release, and | 149 | version. New configuration options are added in each release, and |
145 | odd problems will turn up if the configuration files are not set up | 150 | odd problems will turn up if the configuration files are not set up |
146 | as expected. If you want to carry your existing configuration to a | 151 | as expected. If you want to carry your existing configuration to a |
147 | new version with minimal work, use "make oldconfig", which will | 152 | new version with minimal work, use "make oldconfig", which will |
148 | only ask you for the answers to new questions. | 153 | only ask you for the answers to new questions. |
149 | 154 | ||
150 | - Alternate configuration commands are: | 155 | - Alternate configuration commands are: |
151 | "make menuconfig" Text based color menus, radiolists & dialogs. | 156 | "make menuconfig" Text based color menus, radiolists & dialogs. |
152 | "make xconfig" X windows (Qt) based configuration tool. | 157 | "make xconfig" X windows (Qt) based configuration tool. |
153 | "make gconfig" X windows (Gtk) based configuration tool. | 158 | "make gconfig" X windows (Gtk) based configuration tool. |
154 | "make oldconfig" Default all questions based on the contents of | 159 | "make oldconfig" Default all questions based on the contents of |
155 | your existing ./.config file. | 160 | your existing ./.config file. |
156 | "make silentoldconfig" | 161 | "make silentoldconfig" |
157 | Like above, but avoids cluttering the screen | 162 | Like above, but avoids cluttering the screen |
158 | with questions already answered. | 163 | with questions already answered. |
159 | 164 | ||
160 | NOTES on "make config": | 165 | NOTES on "make config": |
161 | - having unnecessary drivers will make the kernel bigger, and can | 166 | - having unnecessary drivers will make the kernel bigger, and can |
162 | under some circumstances lead to problems: probing for a | 167 | under some circumstances lead to problems: probing for a |
163 | nonexistent controller card may confuse your other controllers | 168 | nonexistent controller card may confuse your other controllers |
164 | - compiling the kernel with "Processor type" set higher than 386 | 169 | - compiling the kernel with "Processor type" set higher than 386 |
165 | will result in a kernel that does NOT work on a 386. The | 170 | will result in a kernel that does NOT work on a 386. The |
166 | kernel will detect this on bootup, and give up. | 171 | kernel will detect this on bootup, and give up. |
167 | - A kernel with math-emulation compiled in will still use the | 172 | - A kernel with math-emulation compiled in will still use the |
168 | coprocessor if one is present: the math emulation will just | 173 | coprocessor if one is present: the math emulation will just |
169 | never get used in that case. The kernel will be slightly larger, | 174 | never get used in that case. The kernel will be slightly larger, |
170 | but will work on different machines regardless of whether they | 175 | but will work on different machines regardless of whether they |
171 | have a math coprocessor or not. | 176 | have a math coprocessor or not. |
172 | - the "kernel hacking" configuration details usually result in a | 177 | - the "kernel hacking" configuration details usually result in a |
173 | bigger or slower kernel (or both), and can even make the kernel | 178 | bigger or slower kernel (or both), and can even make the kernel |
174 | less stable by configuring some routines to actively try to | 179 | less stable by configuring some routines to actively try to |
175 | break bad code to find kernel problems (kmalloc()). Thus you | 180 | break bad code to find kernel problems (kmalloc()). Thus you |
176 | should probably answer 'n' to the questions for | 181 | should probably answer 'n' to the questions for |
177 | "development", "experimental", or "debugging" features. | 182 | "development", "experimental", or "debugging" features. |
178 | 183 | ||
179 | COMPILING the kernel: | 184 | COMPILING the kernel: |
180 | 185 | ||
181 | - Make sure you have gcc 2.95.3 available. | 186 | - Make sure you have gcc 2.95.3 available. |
182 | gcc 2.91.66 (egcs-1.1.2), and gcc 2.7.2.3 are known to miscompile | 187 | gcc 2.91.66 (egcs-1.1.2), and gcc 2.7.2.3 are known to miscompile |
183 | some parts of the kernel, and are *no longer supported*. | 188 | some parts of the kernel, and are *no longer supported*. |
184 | Also remember to upgrade your binutils package (for as/ld/nm and company) | 189 | Also remember to upgrade your binutils package (for as/ld/nm and company) |
185 | if necessary. For more information, refer to Documentation/Changes. | 190 | if necessary. For more information, refer to Documentation/Changes. |
186 | 191 | ||
187 | Please note that you can still run a.out user programs with this kernel. | 192 | Please note that you can still run a.out user programs with this kernel. |
188 | 193 | ||
189 | - Do a "make" to create a compressed kernel image. It is also | 194 | - Do a "make" to create a compressed kernel image. It is also |
190 | possible to do "make install" if you have lilo installed to suit the | 195 | possible to do "make install" if you have lilo installed to suit the |
191 | kernel makefiles, but you may want to check your particular lilo setup first. | 196 | kernel makefiles, but you may want to check your particular lilo setup first. |
192 | 197 | ||
193 | To do the actual install you have to be root, but none of the normal | 198 | To do the actual install you have to be root, but none of the normal |
194 | build should require that. Don't take the name of root in vain. | 199 | build should require that. Don't take the name of root in vain. |
195 | 200 | ||
196 | - If you configured any of the parts of the kernel as `modules', you | 201 | - If you configured any of the parts of the kernel as `modules', you |
197 | will also have to do "make modules_install". | 202 | will also have to do "make modules_install". |
198 | 203 | ||
199 | - Keep a backup kernel handy in case something goes wrong. This is | 204 | - Keep a backup kernel handy in case something goes wrong. This is |
200 | especially true for the development releases, since each new release | 205 | especially true for the development releases, since each new release |
201 | contains new code which has not been debugged. Make sure you keep a | 206 | contains new code which has not been debugged. Make sure you keep a |
202 | backup of the modules corresponding to that kernel, as well. If you | 207 | backup of the modules corresponding to that kernel, as well. If you |
203 | are installing a new kernel with the same version number as your | 208 | are installing a new kernel with the same version number as your |
204 | working kernel, make a backup of your modules directory before you | 209 | working kernel, make a backup of your modules directory before you |
205 | do a "make modules_install". | 210 | do a "make modules_install". |
206 | Alternatively, before compiling, use the kernel config option | 211 | Alternatively, before compiling, use the kernel config option |
207 | "LOCALVERSION" to append a unique suffix to the regular kernel version. | 212 | "LOCALVERSION" to append a unique suffix to the regular kernel version. |
208 | LOCALVERSION can be set in the "General Setup" menu. | 213 | LOCALVERSION can be set in the "General Setup" menu. |
209 | 214 | ||
210 | - In order to boot your new kernel, you'll need to copy the kernel | 215 | - In order to boot your new kernel, you'll need to copy the kernel |
211 | image (e.g. .../linux/arch/i386/boot/bzImage after compilation) | 216 | image (e.g. .../linux/arch/i386/boot/bzImage after compilation) |
212 | to the place where your regular bootable kernel is found. | 217 | to the place where your regular bootable kernel is found. |
213 | 218 | ||
214 | - Booting a kernel directly from a floppy without the assistance of a | 219 | - Booting a kernel directly from a floppy without the assistance of a |
215 | bootloader such as LILO, is no longer supported. | 220 | bootloader such as LILO, is no longer supported. |
216 | 221 | ||
217 | If you boot Linux from the hard drive, chances are you use LILO which | 222 | If you boot Linux from the hard drive, chances are you use LILO which |
218 | uses the kernel image as specified in the file /etc/lilo.conf. The | 223 | uses the kernel image as specified in the file /etc/lilo.conf. The |
219 | kernel image file is usually /vmlinuz, /boot/vmlinuz, /bzImage or | 224 | kernel image file is usually /vmlinuz, /boot/vmlinuz, /bzImage or |
220 | /boot/bzImage. To use the new kernel, save a copy of the old image | 225 | /boot/bzImage. To use the new kernel, save a copy of the old image |
221 | and copy the new image over the old one. Then, you MUST RERUN LILO | 226 | and copy the new image over the old one. Then, you MUST RERUN LILO |
222 | to update the loading map!! If you don't, you won't be able to boot | 227 | to update the loading map!! If you don't, you won't be able to boot |
223 | the new kernel image. | 228 | the new kernel image. |
224 | 229 | ||
225 | Reinstalling LILO is usually a matter of running /sbin/lilo. | 230 | Reinstalling LILO is usually a matter of running /sbin/lilo. |
226 | You may wish to edit /etc/lilo.conf to specify an entry for your | 231 | You may wish to edit /etc/lilo.conf to specify an entry for your |
227 | old kernel image (say, /vmlinux.old) in case the new one does not | 232 | old kernel image (say, /vmlinux.old) in case the new one does not |
228 | work. See the LILO docs for more information. | 233 | work. See the LILO docs for more information. |
229 | 234 | ||
230 | After reinstalling LILO, you should be all set. Shutdown the system, | 235 | After reinstalling LILO, you should be all set. Shutdown the system, |
231 | reboot, and enjoy! | 236 | reboot, and enjoy! |
232 | 237 | ||
233 | If you ever need to change the default root device, video mode, | 238 | If you ever need to change the default root device, video mode, |
234 | ramdisk size, etc. in the kernel image, use the 'rdev' program (or | 239 | ramdisk size, etc. in the kernel image, use the 'rdev' program (or |
235 | alternatively the LILO boot options when appropriate). No need to | 240 | alternatively the LILO boot options when appropriate). No need to |
236 | recompile the kernel to change these parameters. | 241 | recompile the kernel to change these parameters. |
237 | 242 | ||
238 | - Reboot with the new kernel and enjoy. | 243 | - Reboot with the new kernel and enjoy. |
239 | 244 | ||
240 | IF SOMETHING GOES WRONG: | 245 | IF SOMETHING GOES WRONG: |
241 | 246 | ||
242 | - If you have problems that seem to be due to kernel bugs, please check | 247 | - If you have problems that seem to be due to kernel bugs, please check |
243 | the file MAINTAINERS to see if there is a particular person associated | 248 | the file MAINTAINERS to see if there is a particular person associated |
244 | with the part of the kernel that you are having trouble with. If there | 249 | with the part of the kernel that you are having trouble with. If there |
245 | isn't anyone listed there, then the second best thing is to mail | 250 | isn't anyone listed there, then the second best thing is to mail |
246 | them to me (torvalds@osdl.org), and possibly to any other relevant | 251 | them to me (torvalds@osdl.org), and possibly to any other relevant |
247 | mailing-list or to the newsgroup. | 252 | mailing-list or to the newsgroup. |
248 | 253 | ||
249 | - In all bug-reports, *please* tell what kernel you are talking about, | 254 | - In all bug-reports, *please* tell what kernel you are talking about, |
250 | how to duplicate the problem, and what your setup is (use your common | 255 | how to duplicate the problem, and what your setup is (use your common |
251 | sense). If the problem is new, tell me so, and if the problem is | 256 | sense). If the problem is new, tell me so, and if the problem is |
252 | old, please try to tell me when you first noticed it. | 257 | old, please try to tell me when you first noticed it. |
253 | 258 | ||
254 | - If the bug results in a message like | 259 | - If the bug results in a message like |
255 | 260 | ||
256 | unable to handle kernel paging request at address C0000010 | 261 | unable to handle kernel paging request at address C0000010 |
257 | Oops: 0002 | 262 | Oops: 0002 |
258 | EIP: 0010:XXXXXXXX | 263 | EIP: 0010:XXXXXXXX |
259 | eax: xxxxxxxx ebx: xxxxxxxx ecx: xxxxxxxx edx: xxxxxxxx | 264 | eax: xxxxxxxx ebx: xxxxxxxx ecx: xxxxxxxx edx: xxxxxxxx |
260 | esi: xxxxxxxx edi: xxxxxxxx ebp: xxxxxxxx | 265 | esi: xxxxxxxx edi: xxxxxxxx ebp: xxxxxxxx |
261 | ds: xxxx es: xxxx fs: xxxx gs: xxxx | 266 | ds: xxxx es: xxxx fs: xxxx gs: xxxx |
262 | Pid: xx, process nr: xx | 267 | Pid: xx, process nr: xx |
263 | xx xx xx xx xx xx xx xx xx xx | 268 | xx xx xx xx xx xx xx xx xx xx |
264 | 269 | ||
265 | or similar kernel debugging information on your screen or in your | 270 | or similar kernel debugging information on your screen or in your |
266 | system log, please duplicate it *exactly*. The dump may look | 271 | system log, please duplicate it *exactly*. The dump may look |
267 | incomprehensible to you, but it does contain information that may | 272 | incomprehensible to you, but it does contain information that may |
268 | help debugging the problem. The text above the dump is also | 273 | help debugging the problem. The text above the dump is also |
269 | important: it tells something about why the kernel dumped code (in | 274 | important: it tells something about why the kernel dumped code (in |
270 | the above example it's due to a bad kernel pointer). More information | 275 | the above example it's due to a bad kernel pointer). More information |
271 | on making sense of the dump is in Documentation/oops-tracing.txt | 276 | on making sense of the dump is in Documentation/oops-tracing.txt |
272 | 277 | ||
273 | - If you compiled the kernel with CONFIG_KALLSYMS you can send the dump | 278 | - If you compiled the kernel with CONFIG_KALLSYMS you can send the dump |
274 | as is, otherwise you will have to use the "ksymoops" program to make | 279 | as is, otherwise you will have to use the "ksymoops" program to make |
275 | sense of the dump. This utility can be downloaded from | 280 | sense of the dump. This utility can be downloaded from |
276 | ftp://ftp.<country>.kernel.org/pub/linux/utils/kernel/ksymoops. | 281 | ftp://ftp.<country>.kernel.org/pub/linux/utils/kernel/ksymoops. |
277 | Alternately you can do the dump lookup by hand: | 282 | Alternately you can do the dump lookup by hand: |
278 | 283 | ||
279 | - In debugging dumps like the above, it helps enormously if you can | 284 | - In debugging dumps like the above, it helps enormously if you can |
280 | look up what the EIP value means. The hex value as such doesn't help | 285 | look up what the EIP value means. The hex value as such doesn't help |
281 | me or anybody else very much: it will depend on your particular | 286 | me or anybody else very much: it will depend on your particular |
282 | kernel setup. What you should do is take the hex value from the EIP | 287 | kernel setup. What you should do is take the hex value from the EIP |
283 | line (ignore the "0010:"), and look it up in the kernel namelist to | 288 | line (ignore the "0010:"), and look it up in the kernel namelist to |
284 | see which kernel function contains the offending address. | 289 | see which kernel function contains the offending address. |
285 | 290 | ||
286 | To find out the kernel function name, you'll need to find the system | 291 | To find out the kernel function name, you'll need to find the system |
287 | binary associated with the kernel that exhibited the symptom. This is | 292 | binary associated with the kernel that exhibited the symptom. This is |
288 | the file 'linux/vmlinux'. To extract the namelist and match it against | 293 | the file 'linux/vmlinux'. To extract the namelist and match it against |
289 | the EIP from the kernel crash, do: | 294 | the EIP from the kernel crash, do: |
290 | 295 | ||
291 | nm vmlinux | sort | less | 296 | nm vmlinux | sort | less |
292 | 297 | ||
293 | This will give you a list of kernel addresses sorted in ascending | 298 | This will give you a list of kernel addresses sorted in ascending |
294 | order, from which it is simple to find the function that contains the | 299 | order, from which it is simple to find the function that contains the |
295 | offending address. Note that the address given by the kernel | 300 | offending address. Note that the address given by the kernel |
296 | debugging messages will not necessarily match exactly with the | 301 | debugging messages will not necessarily match exactly with the |
297 | function addresses (in fact, that is very unlikely), so you can't | 302 | function addresses (in fact, that is very unlikely), so you can't |
298 | just 'grep' the list: the list will, however, give you the starting | 303 | just 'grep' the list: the list will, however, give you the starting |
299 | point of each kernel function, so by looking for the function that | 304 | point of each kernel function, so by looking for the function that |
300 | has a starting address lower than the one you are searching for but | 305 | has a starting address lower than the one you are searching for but |
301 | is followed by a function with a higher address you will find the one | 306 | is followed by a function with a higher address you will find the one |
302 | you want. In fact, it may be a good idea to include a bit of | 307 | you want. In fact, it may be a good idea to include a bit of |
303 | "context" in your problem report, giving a few lines around the | 308 | "context" in your problem report, giving a few lines around the |
304 | interesting one. | 309 | interesting one. |
305 | 310 | ||
306 | If you for some reason cannot do the above (you have a pre-compiled | 311 | If you for some reason cannot do the above (you have a pre-compiled |
307 | kernel image or similar), telling me as much about your setup as | 312 | kernel image or similar), telling me as much about your setup as |
308 | possible will help. | 313 | possible will help. |
309 | 314 | ||
310 | - Alternately, you can use gdb on a running kernel. (read-only; i.e. you | 315 | - Alternately, you can use gdb on a running kernel. (read-only; i.e. you |
311 | cannot change values or set break points.) To do this, first compile the | 316 | cannot change values or set break points.) To do this, first compile the |
312 | kernel with -g; edit arch/i386/Makefile appropriately, then do a "make | 317 | kernel with -g; edit arch/i386/Makefile appropriately, then do a "make |
313 | clean". You'll also need to enable CONFIG_PROC_FS (via "make config"). | 318 | clean". You'll also need to enable CONFIG_PROC_FS (via "make config"). |
314 | 319 | ||
315 | After you've rebooted with the new kernel, do "gdb vmlinux /proc/kcore". | 320 | After you've rebooted with the new kernel, do "gdb vmlinux /proc/kcore". |
316 | You can now use all the usual gdb commands. The command to look up the | 321 | You can now use all the usual gdb commands. The command to look up the |
317 | point where your system crashed is "l *0xXXXXXXXX". (Replace the XXXes | 322 | point where your system crashed is "l *0xXXXXXXXX". (Replace the XXXes |
318 | with the EIP value.) | 323 | with the EIP value.) |
319 | 324 | ||
320 | gdb'ing a non-running kernel currently fails because gdb (wrongly) | 325 | gdb'ing a non-running kernel currently fails because gdb (wrongly) |
321 | disregards the starting offset for which the kernel is compiled. | 326 | disregards the starting offset for which the kernel is compiled. |
322 | 327 | ||
323 | 328 |