Eric Lee / linux-smarc-t335x-v3.2

Download as
Browse Code ยป

Commit b39f72fef241ce0ce971ed21922b4d64aefaf916

Authored by Horms
Committed by Linus Torvalds
1 parent 82da2c3727
Exists in master and in 4 other branches v3.2_AM335xPSP_04.06.00.11, v3.2_NEWT335xPSP_04.06.00.11, v3.2_SBC_SMARTMEN, v3.2_SMARCT335xPSP_04.06.00.11

[PATCH] README doesn't mention bzip2 source tarball 

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Showing 1 changed file with 4 additions and 0 deletions Inline Diff

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