Hi... Let's see if I can clear some of your doubts... On Sun, Sep 19, 2010 at 06:19, Sri Ram Vemulpali <sri.ram.gmu06@xxxxxxxxx> wrote: > Also, why is the IDT entry is 8 bytes long. IIRC, because it contains the segmen descriptor (not really sure about the term) and address of the handler. Usually I name it CS:IP--> Code Segment : Instruction Pointer. >And how is the interrupt line > sharing is provided. Is sharing provided at OS code level. AFAIK, interrupt sharing is set up by "plugging" several devices into same address, due to the usage of the same IRQ line. IMO it is the BIOS (or APIC? Perhaps local APIC) job. Short story, the devices first are probed in which interrupt line they wish to stay, and in the case of interrupt sharing, BIOS plug them into same bus/interrupt line. In OS level, a handler for each devices are setup with IRQ_SHARING (or IRQ_SHARED?) flag. The consequence is, for every interrupt shot, all devices which share this same IRQ line are executed. It is a task of the testing logic inside the each handlers themselves to find out which device that really responsible to handle it. -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
