Debugging jądra, część II

root@stargate:~# touch test.txt
root@stargate:~# echo Plik testowy linia 1 >> test.txt
root@stargate:~# echo Plik testowy linia 2 >> test.txt
root@stargate:~# stty ispeed 115200 ospeed 115200 -F /dev/ttyS0

root@kam:~# stty ispeed 115200 ospeed 115200 -F /dev/ttyS0
root@kam:~# cat /dev/ttyS0

root@stargate:~# cat test.txt > /dev/ttyS0
root@stargate:~# echo lol > /dev/ttyS0

Plik testowy linia 1

Plik testowy linia 2

lol

root@kam:~#cvs -d:pserver:anonymous@kgdb.cvs.sourceforge.net:/cvsroot/kgdb login
root@kam:~#cvs -z3 -d:pserver:anonymous@kgdb.cvs.sourceforge.net:/cvsroot/kgdb co -r linux2_6_17 .

root@kam:~#cp -r kgdb-2 /usr/src/ 
root@kam:~#cd /usr/src/linux-2.6.17.13 
root@kam:~# for p in $(grep patch ../kgdb-2/series);do patch -p1 -si ../kgdb-2/$p;done

root@kam:~#make mrproper
root@kam:~#make menuconfig

root@kam:~#make bzImage && make modules

(gdb) step 4
[New thread 32768]
90                              status |= action->flags;
(gdb) c
Continuing.

Program received signal SIGTRAP, Trace/breakpoint trap.
breakpoint () at kernel/kgdb.c:1691
1691            atomic_set(&kgdb_setting_breakpoint, 0);
(gdb) step 3
handle_IRQ_event (irq=4, regs=0xc02c5fa8, action=0xdff56440) at kernel/irq/handle.c:89
89                      if (ret == IRQ_HANDLED)
(gdb) list
84              if (!(action->flags & SA_INTERRUPT))
85                      local_irq_enable();
86
87              do {
88                      ret = action->handler(irq, action->dev_id, regs);
89                      if (ret == IRQ_HANDLED)
90                              status |= action->flags;
91                      retval |= ret;
92                      action = action->next;
93              } while (action);
(gdb) break 92
Breakpoint 1 at 0xc0129dd2: file kernel/irq/handle.c, line 92.
(gdb) c
Continuing.

Breakpoint 1, handle_IRQ_event (irq=0, regs=0xc02c5f38, action=0xc027f360) at kernel/irq/handle.c:92
92                      action = action->next;
(gdb) info breakpoints
Num Type           Disp Enb Address    What
1   breakpoint     keep y   0xc0129dd2 in handle_IRQ_event at kernel/irq/handle.c:92
        breakpoint already hit 1 time
(gdb) disable 1
(gdb) break
Note: breakpoint 1 (disabled) also set at pc 0xc0129dd2.
Breakpoint 2 at 0xc0129dd2: file kernel/irq/handle.c, line 92.
(gdb) info breakpoints
Num Type           Disp Enb Address    What
1   breakpoint     keep n   0xc0129dd2 in handle_IRQ_event at kernel/irq/handle.c:92
        breakpoint already hit 1 time
2   breakpoint     keep y   0xc0129dd2 in handle_IRQ_event at kernel/irq/handle.c:92
(gdb) re
refresh         remote          restart         restore         return          reverse-search
(gdb) delete
breakpoints  checkpoint   display      mem          tracepoints
(gdb) help delete
Delete some breakpoints or auto-display expressions.
Arguments are breakpoint numbers with spaces in between.
To delete all breakpoints, give no argument.

Also a prefix command for deletion of other GDB objects.
The "unset" command is also an alias for "delete".

List of delete subcommands:

delete breakpoints -- Delete some breakpoints or auto-display expressions
delete checkpoint -- Delete a fork/checkpoint (experimental)
delete display -- Cancel some expressions to be displayed when program stops
delete mem -- Delete memory region
delete tracepoints -- Delete specified tracepoints

Type "help delete" followed by delete subcommand name for full documentation.
Command name abbreviations are allowed if unambiguous.
(gdb) help delete breakpoints
Delete some breakpoints or auto-display expressions.
Arguments are breakpoint numbers with spaces in between.
To delete all breakpoints, give no argument.
This command may be abbreviated "delete".
(gdb) delete breakpoints 1
(gdb) info breakpoints
Num Type           Disp Enb Address    What
2   breakpoint     keep y   0xc0129dd2 in handle_IRQ_event at kernel/irq/handle.c:92
(gdb) bt
#0  handle_IRQ_event (irq=0, regs=0xc02c5f38, action=0xc027f360) at kernel/irq/handle.c:92
#1  0xc0129e4d in __do_IRQ (irq=0, regs=0xc02c5f38) at kernel/irq/handle.c:173
#2  0xc010417c in do_IRQ (regs=0xc02c5f38) at arch/i386/kernel/irq.c:108
#3  0xc0102b16 in common_interrupt () at include/asm/current.h:9
#4  0xdff56440 in ?? ()
#5  0x00000000 in ?? ()
(gdb) l 92
87              do {
88                      ret = action->handler(irq, action->dev_id, regs);
89                      if (ret == IRQ_HANDLED)
90                              status |= action->flags;
91                      retval |= ret;
92                      action = action->next;
93              } while (action);
94
95              if (status & SA_SAMPLE_RANDOM)
96                      add_interrupt_randomness(irq);
(gdb) print retval
$1 = 0
(gdb) print action
$2 = (struct irqaction *) 0xc027f360
(gdb)quit
The program is running.  Exit anyway? (y or n) y
root@stargate:/usr/src/linux-2.6.17.13#

root@stargate:/usr/src/linux-2.6.17.13# make menuconfig ARCH=mu

root@stargate:/usr/src/linux-2.6.17.13# make ARCH=mu

root@stargate:~/uml# ./linux-2.6.17.13 ubda=Slackware-11-root_fs mem=64M

root@darkstar:~# mkdir modules
root@darkstar:~# mount none modules -t hostfs -o /usr/src/linux-2.6.17.13
root@darkstar:~# cd modules
root@darkstar:~/src# make modules_install

root@stargate:~/uml# mkdir fs
root@stargate:~/uml# mount Slackware-11-root_fs fs -o loop
root@stargate:~/uml# cd /usr/src/linux-2.6.17.13
root@stargate:~/usr/src/linux-2.6.17.13# make modules_install INSTALL_MOD_PATH=~/uml/fs
root@stargate:~/uml# umount fs