Thanks for the reply, > On Thu, May 22, 2008 at 12:43 AM, Mayank Kaushik > <mayank.utexas@xxxxxxxxx> wrote: >> I have been reading Chapter 9 of the Intel Processor Manuals, Vol 3A >> (System Programming Guide), which details the APIC. >> I have noticed that we often have to add the noapic and nolapic >> arguments to the kernel command line to make devices like the wireless >> card work. The explanation for these options simply stated that this >> is to overcome "buggy bios implementations". I read a little more, and it seems like "noapic" turns off the I/O Apic in the chipset (and causes the old 8259 to be used, probably) while "nolapic" turns off the Local Apic in the processor. I hope i'm not mistaken. Will update if/when i get a clearer picture. >> >> Can someone here explain what could possibly be the bug in the bios >> that necessitates the use of these arguments? Further, what does the >> kernel do differently when it sees these arguments? > > simple, it reverts back to the old PIC. Old PIC, to the best I know, > is slower, it's not "installed" per processor. Thus, one of the effect > is, it send interrupts globally, making the whole processors turn > their attention to every interrupts. > > regards, > > Mulyadi. > Thanks, Mayank -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
