Dear all, in arch/i386/kernel/entry.S exist lcall7 and lcall27. However, I do not understand why the same coding -- except for pushl $0x07 in lcall7 and the respective pushl $0x27 in lcall27 -- is written. As written in the subject, I refer currently 2.4.17. The real issue why I am writing: The Interrupts and exception handling is not fully clear to me in Linux on a ia32. I know the IDT has to be setup. setup.c handles this, if I correctly remember. But where is the code stored? I do not find the Assembler or C Code for the timer, the serial line 1 etc. for example. I assume that the IRQ/exception handling works the following way that the function-pointers stored in the IDT direct the execution to wrapper which prepare a unified stack layout. Then the execution is continued at a unified assembler function that dispatches the call to the real ISRs. Am I wrong? In short, does anyone know full sequence of steps that take place when an interrupt is raised either in kernel or in user mode? Which functions get called, and, where are they stored in the source code? Thanks in advance for any help! wbr, Lukas -- Lukas Ruf http://www.lpr.ch Join rawip@rawip.org on http://www.rawip.org -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
