Hi, I've got a dual-processor system built around the Intel SBT2 motherboard, which uses the ServerWorks LE chipset. 2.4.3 SMP works fine. When I build a UP kernel with IO-APIC support, I get this during boot: [... everything seems ok until ...] Uniform Multi-Platform E-IDE driver Revision: 6.31 ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx ServerWorks OSB4: IDE controller on PCI bus 00 dev 79 ServerWorks OSB4: chipset revision 0 ServerWorks OSB4: not 100% native mode: will probe irqs later ide0: BM-DMA at 0x0840-0x0847, BIOS settings: hda:DMA, hdb:DMA ide1: BM-DMA at 0x0848-0x084f, BIOS settings: hdc:DMA, hdd:DMA spurious APIC interrupt on CPU#0, should never happen. spurious APIC interrupt on CPU#0, should never happen. hda: CD-ROM 52X/AKH, ATAPI CD/DVD-ROM drive spurious APIC interrupt on CPU#0, should never happen. spurious APIC interrupt on CPU#0, should never happen. ide0 at 0x1f0-0x1f7,0x3f6 on irq 14 spurious APIC interrupt on CPU#0, should never happen. spurious APIC interrupt on CPU#0, should never happen. hda: lost interrupt spurious APIC interrupt on CPU#0, should never happen. hda: lost interrupt hda: ATAPI 52X CD-ROM drive, 192kB Cache, UDMA(33) Uniform CD-ROM driver Revision: 3.12 Floppy drive(s): fd0 is 1.44M spurious APIC interrupt on CPU#0, should never happen. spurious APIC interrupt on CPU#0, should never happen. floppy0: no floppy controllers found Serial driver version 5.05 (2000-12-13) with MANY_PORTS SHARE_IRQ SERIAL_PCI ISAPNP enabled ttyS00 at 0x03f8 (irq = 4) is a 16550A ttyS01 at 0x02f8 (irq = 3) is a 16550A SCSI subsystem driver Revision: 1.00 (scsi0) <Adaptec AIC-7899 Ultra 160/m SCSI host adapter> found at PCI 1/4/0 (scsi0) Wide Channel A, SCSI ID=7, 32/255 SCBs (scsi0) Downloading sequencer code... 392 instructions downloaded (scsi1) <Adaptec AIC-7899 Ultra 160/m SCSI host adapter> found at PCI 1/4/1 (scsi1) Wide Channel B, SCSI ID=7, 32/255 SCBs (scsi1) Downloading sequencer code... 392 instructions downloaded scsi0 : Adaptec AHA274x/284x/294x (EISA/VLB/PCI-Fast SCSI) 5.2.1/5.2.0 <Adaptec AIC-7899 Ultra 160/m SCSI host adapter> scsi1 : Adaptec AHA274x/284x/294x (EISA/VLB/PCI-Fast SCSI) 5.2.1/5.2.0 <Adaptec AIC-7899 Ultra 160/m SCSI host adapter> scsi : aborting command due to timeout : pid 0, scsi0, channel 0, id 0, lun 0 Inquiry 00 00 00 ff 00 spurious APIC interrupt on CPU#0, should never happen. SCSI host 0 abort (pid 0) timed out - resetting SCSI bus is being reset for host 0 channel 0. spurious APIC interrupt on CPU#0, should never happen. SCSI host 0 channel 0 reset (pid 0) timed out - trying harder SCSI bus is being reset for host 0 channel 0. [... repeat above 6 lines until I reset hw ...] 2.4.3 has this behavior, 2.4.3-ac9 works fine. I found this in the -ac changelog; perhaps it's relevant: > 2.4.2-ac12 [...] > o Remove serverworks handling. The BIOS is our (me) > best (and right now only) hope for that chip Here's the pertinent (I think) part of 2.4.3 .config: CONFIG_MPENTIUMIII=y CONFIG_X86_GOOD_APIC=y # CONFIG_SMP is not set CONFIG_X86_UP_IOAPIC=y CONFIG_X86_IO_APIC=y CONFIG_X86_LOCAL_APIC=y Details available on request. Thanks -- Jim -- Jim Schutt <[EMAIL PROTECTED]> Sandia National Laboratories, Albuquerque, New Mexico USA - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/