Hi Jason, Just to be complete the kernel config might be useful in reproducing the bug. I'm running Ubuntu 8.04 - the Hardy Heron - released in April 2008. Jason Wessel wrote: > Denis Joseph Barrow wrote: >> Hi ladies/gentlemen, >> The kernel I'm running gdb with is 2.6.27-rc4 >> The false sigtrap is occuring in ia32_sysenter_target in arch/x86/kernel/entry_32.S:303 >> when gdb is stepped from the user process as described below >> >> > > Your example does not indicate how or why you setup kgdb. kgdb can be > compiled into the kernel, but it should not have any effect what so ever > unless it is configured for use because it will not register to receive > any of the breakpoint or single stepping traps. > > Perhaps there is more to the description of your problem? > > Jason. > >> To reproduce >> compile kernel with kgdb support >> compile my randsleep program attached using the .mk script >> as root >> attach randsleep to an idle serial port e.g. /dev/ttyS0 by typing >> randsleep /dev/ttyS0 >> from another bash shell type >> ps -aux | grep randsleep >> >> gdb ./randsleep >> attach >> >> You should get messages from gdb like >> Attaching to program: /home/djbarrow/devel2/randsleep/randsleep, process 6397 >> Reading symbols from /lib/tls/i686/cmov/libc.so.6...done. >> Loaded symbols for /lib/tls/i686/cmov/libc.so.6 >> Reading symbols from /lib/ld-linux.so.2...done. >> Loaded symbols for /lib/ld-linux.so.2 >> 0xb7fda430 in __kernel_vsyscall () >> >> Now type step. >> >> The machine is now hung until gdb attaches remotely. >> >> >> -- best regards, D.J. Barrow