Re: Incompatibility between 'Local APIC' and '8139too'

From: Mikael Pettersson (
Date: Mon Feb 10 2003 - 20:45:33 EST

On Tue, 11 Feb 2003 00:47:12 +0100, Nicolas Baradakis wrote:
>Activating the option 'Local APIC support on uniprocessors' prevents
>the network device '8139too' from transmitting any packet.
>The workaround is to boot the kernel with the option 'noapic' or
>recompile it without the option 'Local APIC', and then the network
>device works perfectly.
>>From the debian package 'kernel-source-2.4.20_2.4.20-5_all.deb'

I strongly believe your problems are related to the I/O APIC,
not the local APIC:

- the local APIC has minimal impact on system-level IRQ handling,
  whereas the impact from the I/O APIC by definition is major

- the 'noapic' option disables the I/O APIC, NOT the local APIC
  (at least in all standard kernels, Debian may have broken this)

- disabling the local APIC kernel option also disables I/O
  APIC on uniprocessor support
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This archive was generated by hypermail 2b29 : Sat Feb 15 2003 - 22:00:31 EST