Loading .gitignore +3 −0 Original line number Diff line number Diff line Loading @@ -16,6 +16,7 @@ # # Top-level generic files # tags vmlinux* System.map Module.symvers Loading @@ -30,3 +31,5 @@ include/linux/autoconf.h include/linux/compile.h include/linux/version.h # stgit generated dirs patches-* CREDITS +4 −5 Original line number Diff line number Diff line Loading @@ -120,7 +120,6 @@ D: Author of lil (Linux Interrupt Latency benchmark) D: Fixed the shm swap deallocation at swapoff time (try_to_unuse message) D: VM hacker D: Various other kernel hacks S: Via Cicalini 26 S: Imola 40026 S: Italy Loading Loading @@ -2814,6 +2813,8 @@ E: luca.risolia@studio.unibo.it P: 1024D/FCE635A4 88E8 F32F 7244 68BA 3958 5D40 99DA 5D2A FCE6 35A4 D: V4L driver for W996[87]CF JPEG USB Dual Mode Camera Chips D: V4L2 driver for SN9C10x PC Camera Controllers D: V4L2 driver for ET61X151 and ET61X251 PC Camera Controllers D: V4L2 driver for ZC0301 Image Processor and Control Chip S: Via Liberta' 41/A S: Osio Sotto, 24046, Bergamo S: Italy Loading Loading @@ -3643,11 +3644,9 @@ S: Cambridge. CB1 7EG S: England N: Chris Wright E: chrisw@osdl.org E: chrisw@sous-sol.org D: hacking on LSM framework and security modules. S: c/o OSDL S: 12725 SW Millikan Way, Suite 400 S: Beaverton, OR 97005 S: Portland, OR S: USA N: Michal Wronski Loading Documentation/BUG-HUNTING +113 −0 Original line number Diff line number Diff line Table of contents ================= Last updated: 20 December 2005 Contents ======== - Introduction - Devices not appearing - Finding patch that caused a bug -- Finding using git-bisect -- Finding it the old way - Fixing the bug Introduction ============ Always try the latest kernel from kernel.org and build from source. If you are not confident in doing that please report the bug to your distribution vendor instead of to a kernel developer. Finding bugs is not always easy. Have a go though. If you can't find it don't give up. Report as much as you have found to the relevant maintainer. See MAINTAINERS for who that is for the subsystem you have worked on. Before you submit a bug report read REPORTING-BUGS. Devices not appearing ===================== Often this is caused by udev. Check that first before blaming it on the kernel. Finding patch that caused a bug =============================== Finding using git-bisect ------------------------ Using the provided tools with git makes finding bugs easy provided the bug is reproducible. Steps to do it: - start using git for the kernel source - read the man page for git-bisect - have fun Finding it the old way ---------------------- [Sat Mar 2 10:32:33 PST 1996 KERNEL_BUG-HOWTO lm@sgi.com (Larry McVoy)] This is how to track down a bug if you know nothing about kernel hacking. Loading Loading @@ -90,3 +143,63 @@ it does work and it lets non-hackers help fix bugs. And it is cool because Linux snapshots will let you do this - something that you can't do with vendor supplied releases. Fixing the bug ============== Nobody is going to tell you how to fix bugs. Seriously. You need to work it out. But below are some hints on how to use the tools. To debug a kernel, use objdump and look for the hex offset from the crash output to find the valid line of code/assembler. Without debug symbols, you will see the assembler code for the routine shown, but if your kernel has debug symbols the C code will also be available. (Debug symbols can be enabled in the kernel hacking menu of the menu configuration.) For example: objdump -r -S -l --disassemble net/dccp/ipv4.o NB.: you need to be at the top level of the kernel tree for this to pick up your C files. If you don't have access to the code you can also debug on some crash dumps e.g. crash dump output as shown by Dave Miller. > EIP is at ip_queue_xmit+0x14/0x4c0 > ... > Code: 44 24 04 e8 6f 05 00 00 e9 e8 fe ff ff 8d 76 00 8d bc 27 00 00 > 00 00 55 57 56 53 81 ec bc 00 00 00 8b ac 24 d0 00 00 00 8b 5d 08 > <8b> 83 3c 01 00 00 89 44 24 14 8b 45 28 85 c0 89 44 24 18 0f 85 > > Put the bytes into a "foo.s" file like this: > > .text > .globl foo > foo: > .byte .... /* bytes from Code: part of OOPS dump */ > > Compile it with "gcc -c -o foo.o foo.s" then look at the output of > "objdump --disassemble foo.o". > > Output: > > ip_queue_xmit: > push %ebp > push %edi > push %esi > push %ebx > sub $0xbc, %esp > mov 0xd0(%esp), %ebp ! %ebp = arg0 (skb) > mov 0x8(%ebp), %ebx ! %ebx = skb->sk > mov 0x13c(%ebx), %eax ! %eax = inet_sk(sk)->opt Another very useful option of the Kernel Hacking section in menuconfig is Debug memory allocations. This will help you see whether data has been initialised and not set before use etc. To see the values that get assigned with this look at mm/slab.c and search for POISON_INUSE. When using this an Oops will often show the poisoned data instead of zero which is the default. Once you have worked out a fix please submit it upstream. After all open source is about sharing what you do and don't you want to be recognised for your genius? Please do read Documentation/SubmittingPatches though to help your code get accepted. Documentation/Changes +0 −18 Original line number Diff line number Diff line Loading @@ -15,24 +15,6 @@ and therefore owes credit to the same people as that file (Jared Mauch, Axel Boldt, Alessandro Sigala, and countless other users all over the 'net). The latest revision of this document, in various formats, can always be found at <http://cyberbuzz.gatech.edu/kaboom/linux/Changes-2.4/>. Feel free to translate this document. If you do so, please send me a URL to your translation for inclusion in future revisions of this document. Smotrite file <http://oblom.rnc.ru/linux/kernel/Changes.ru>, yavlyaushisya russkim perevodom dannogo documenta. Visite <http://www2.adi.uam.es/~ender/tecnico/> para obtener la traducción al español de este documento en varios formatos. Eine deutsche Version dieser Datei finden Sie unter <http://www.stefan-winter.de/Changes-2.4.0.txt>. Chris Ricker (kaboom@gatech.edu or chris.ricker@genetics.utah.edu). Current Minimal Requirements ============================ Loading Documentation/DocBook/Makefile +1 −1 Original line number Diff line number Diff line Loading @@ -9,7 +9,7 @@ DOCBOOKS := wanbook.xml z8530book.xml mcabook.xml videobook.xml \ kernel-hacking.xml kernel-locking.xml deviceiobook.xml \ procfs-guide.xml writing_usb_driver.xml \ sis900.xml kernel-api.xml journal-api.xml lsm.xml usb.xml \ kernel-api.xml journal-api.xml lsm.xml usb.xml \ gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml ### Loading Loading
.gitignore +3 −0 Original line number Diff line number Diff line Loading @@ -16,6 +16,7 @@ # # Top-level generic files # tags vmlinux* System.map Module.symvers Loading @@ -30,3 +31,5 @@ include/linux/autoconf.h include/linux/compile.h include/linux/version.h # stgit generated dirs patches-*
CREDITS +4 −5 Original line number Diff line number Diff line Loading @@ -120,7 +120,6 @@ D: Author of lil (Linux Interrupt Latency benchmark) D: Fixed the shm swap deallocation at swapoff time (try_to_unuse message) D: VM hacker D: Various other kernel hacks S: Via Cicalini 26 S: Imola 40026 S: Italy Loading Loading @@ -2814,6 +2813,8 @@ E: luca.risolia@studio.unibo.it P: 1024D/FCE635A4 88E8 F32F 7244 68BA 3958 5D40 99DA 5D2A FCE6 35A4 D: V4L driver for W996[87]CF JPEG USB Dual Mode Camera Chips D: V4L2 driver for SN9C10x PC Camera Controllers D: V4L2 driver for ET61X151 and ET61X251 PC Camera Controllers D: V4L2 driver for ZC0301 Image Processor and Control Chip S: Via Liberta' 41/A S: Osio Sotto, 24046, Bergamo S: Italy Loading Loading @@ -3643,11 +3644,9 @@ S: Cambridge. CB1 7EG S: England N: Chris Wright E: chrisw@osdl.org E: chrisw@sous-sol.org D: hacking on LSM framework and security modules. S: c/o OSDL S: 12725 SW Millikan Way, Suite 400 S: Beaverton, OR 97005 S: Portland, OR S: USA N: Michal Wronski Loading
Documentation/BUG-HUNTING +113 −0 Original line number Diff line number Diff line Table of contents ================= Last updated: 20 December 2005 Contents ======== - Introduction - Devices not appearing - Finding patch that caused a bug -- Finding using git-bisect -- Finding it the old way - Fixing the bug Introduction ============ Always try the latest kernel from kernel.org and build from source. If you are not confident in doing that please report the bug to your distribution vendor instead of to a kernel developer. Finding bugs is not always easy. Have a go though. If you can't find it don't give up. Report as much as you have found to the relevant maintainer. See MAINTAINERS for who that is for the subsystem you have worked on. Before you submit a bug report read REPORTING-BUGS. Devices not appearing ===================== Often this is caused by udev. Check that first before blaming it on the kernel. Finding patch that caused a bug =============================== Finding using git-bisect ------------------------ Using the provided tools with git makes finding bugs easy provided the bug is reproducible. Steps to do it: - start using git for the kernel source - read the man page for git-bisect - have fun Finding it the old way ---------------------- [Sat Mar 2 10:32:33 PST 1996 KERNEL_BUG-HOWTO lm@sgi.com (Larry McVoy)] This is how to track down a bug if you know nothing about kernel hacking. Loading Loading @@ -90,3 +143,63 @@ it does work and it lets non-hackers help fix bugs. And it is cool because Linux snapshots will let you do this - something that you can't do with vendor supplied releases. Fixing the bug ============== Nobody is going to tell you how to fix bugs. Seriously. You need to work it out. But below are some hints on how to use the tools. To debug a kernel, use objdump and look for the hex offset from the crash output to find the valid line of code/assembler. Without debug symbols, you will see the assembler code for the routine shown, but if your kernel has debug symbols the C code will also be available. (Debug symbols can be enabled in the kernel hacking menu of the menu configuration.) For example: objdump -r -S -l --disassemble net/dccp/ipv4.o NB.: you need to be at the top level of the kernel tree for this to pick up your C files. If you don't have access to the code you can also debug on some crash dumps e.g. crash dump output as shown by Dave Miller. > EIP is at ip_queue_xmit+0x14/0x4c0 > ... > Code: 44 24 04 e8 6f 05 00 00 e9 e8 fe ff ff 8d 76 00 8d bc 27 00 00 > 00 00 55 57 56 53 81 ec bc 00 00 00 8b ac 24 d0 00 00 00 8b 5d 08 > <8b> 83 3c 01 00 00 89 44 24 14 8b 45 28 85 c0 89 44 24 18 0f 85 > > Put the bytes into a "foo.s" file like this: > > .text > .globl foo > foo: > .byte .... /* bytes from Code: part of OOPS dump */ > > Compile it with "gcc -c -o foo.o foo.s" then look at the output of > "objdump --disassemble foo.o". > > Output: > > ip_queue_xmit: > push %ebp > push %edi > push %esi > push %ebx > sub $0xbc, %esp > mov 0xd0(%esp), %ebp ! %ebp = arg0 (skb) > mov 0x8(%ebp), %ebx ! %ebx = skb->sk > mov 0x13c(%ebx), %eax ! %eax = inet_sk(sk)->opt Another very useful option of the Kernel Hacking section in menuconfig is Debug memory allocations. This will help you see whether data has been initialised and not set before use etc. To see the values that get assigned with this look at mm/slab.c and search for POISON_INUSE. When using this an Oops will often show the poisoned data instead of zero which is the default. Once you have worked out a fix please submit it upstream. After all open source is about sharing what you do and don't you want to be recognised for your genius? Please do read Documentation/SubmittingPatches though to help your code get accepted.
Documentation/Changes +0 −18 Original line number Diff line number Diff line Loading @@ -15,24 +15,6 @@ and therefore owes credit to the same people as that file (Jared Mauch, Axel Boldt, Alessandro Sigala, and countless other users all over the 'net). The latest revision of this document, in various formats, can always be found at <http://cyberbuzz.gatech.edu/kaboom/linux/Changes-2.4/>. Feel free to translate this document. If you do so, please send me a URL to your translation for inclusion in future revisions of this document. Smotrite file <http://oblom.rnc.ru/linux/kernel/Changes.ru>, yavlyaushisya russkim perevodom dannogo documenta. Visite <http://www2.adi.uam.es/~ender/tecnico/> para obtener la traducción al español de este documento en varios formatos. Eine deutsche Version dieser Datei finden Sie unter <http://www.stefan-winter.de/Changes-2.4.0.txt>. Chris Ricker (kaboom@gatech.edu or chris.ricker@genetics.utah.edu). Current Minimal Requirements ============================ Loading
Documentation/DocBook/Makefile +1 −1 Original line number Diff line number Diff line Loading @@ -9,7 +9,7 @@ DOCBOOKS := wanbook.xml z8530book.xml mcabook.xml videobook.xml \ kernel-hacking.xml kernel-locking.xml deviceiobook.xml \ procfs-guide.xml writing_usb_driver.xml \ sis900.xml kernel-api.xml journal-api.xml lsm.xml usb.xml \ kernel-api.xml journal-api.xml lsm.xml usb.xml \ gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml ### Loading