Hallo, The following patch added in 2.4.0test8-pre4 breaks ups (an alternative source level debugger that does not use gdb): --- v2.4.0-test7/linux/arch/i386/kernel/ptrace.c Fri Jun 23 21:55:07 2000 +++ linux/arch/i386/kernel/ptrace.c Sat Sep 2 12:00:02 2000 @@ -99,6 +99,11 @@ case EFL: value &= FLAG_MASK; value |= get_stack_long(child, EFL_OFFSET) & ~FLAG_MASK; + break; + case EIP: + /* Mark us as not being in a system call, so that no restart +issues happen */ + put_stack_long(child, 4*ORIG_EAX - sizeof(struct pt_regs), -1); + break; } if (regno > GS*4) regno -= 2*4; When it tries to set EIP after the first break point the program crashes now: [....] ptrace(PTRACE_PEEKTEXT, 500, 0x4000ab10, [0x89e58955]) = 0 ptrace(PTRACE_POKETEXT, 500, 0x4000ab10, 0x89e589cc) = 0 ptrace(PTRACE_POKEUSER, 500, 4*EIP, 0x8048406) = 0 ptrace(PTRACE_SINGLESTEP, 500, 0x1, 0) = 0 --- SIGCHLD (Child exited) --- rt_sigaction(SIGIO, {0x80c9f80, [PROF IO], 0}, {SIG_DFL}) = 0 fcntl(4, F_SETFL, O_RDONLY|O_ASYNC) = 0 wait4(-1, [WIFSIGNALED(s) && WTERMSIG(s) == SIGSEGV], WNOHANG, NULL) = 500 With the EIP patch reverted it works fine again. I propose to revert the patch. -Andi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/