I have an ASUS CUV4X-D Dual Processor Mainboard based on a VIA 694XDP chipset. I notice from the archives that someone else has also reported a lockup with the m/b when using two cpus and have some info that may be useful to track it down. Using kernel 2.4.5 the kernel locks up sporadically at boot time. When I enable the NMI watchdog it occasionally gets enabled prior to the lockup and perhaps can be useful for debugging the problem. Here's what happens: I typed this in, so there may be typos: ..TIMER: vector=49 pin1=2 pin2=0 activating NMI Watchdog ... done. [locks up here, or before activating NMI watchdog] [this normally happens next but not in this case number of MP IRQ sources: 21. number of IO-APIC #2 registers: 24. testing the IO APIC....................... ] NMI Watchdog detected LOCKUP on CPU1, registers: CPU : 1 EIP: 0010:[<c0235cdb>] EFLAGS: 00000246 eax: 00000000 ebx: 00000000 ecx: 00000001 edx: 00000001 esi: 00000000 edi: 00000000 ebp: 00000000 esp: cfff5fa4 ds: 0018 es: 0018 ss: 0018 Process swapper (pid: 0, stackpage = cfff5000) Stack: 00000000 00000000 00000000 00000000 c0235e8f 00000001 00000002 c0235eaa 00000000 00000019 00000000 c1442000 00002700 0000b00f 00000000 00000000 0000000d 0000000e 00000000 00000000 c00bcf60 00000000 c0172029 Call Trace: [<c0172029>] Code: 85 c0 74 bf 00 e0 ff ff 21 e7 31 f6 bd 10 00 00 00 31 db Console shuts up ... [ksymoops output] Warning (compare_maps): ksyms_base symbol __VERSIONED_SYMBOL(shmem_file_setup) not found in System.map. Ignoring ksyms_base entry activating NMI Watchdog ... done. [locks up here, or before activating NMI watchdog] NMI Watchdog detected LOCKUP on CPU1, registers: EIP: 0010:[<c0235cdb>] Using defaults from ksymoops -t elf32-i386 -a i386 EFLAGS: 00000246 eax: 00000000 ebx: 00000000 ecx: 00000001 edx: 00000001 esi: 00000000 edi: 00000000 ebp: 00000000 esp: cfff5fa4 ds: 0018 es: 0018 ss: 0018 Stack: 00000000 00000000 00000000 00000000 c0235e8f 00000001 00000002 c0235eaa 00000000 00000019 00000000 c1442000 00002700 0000b00f 00000000 00000000 0000000d 0000000e 00000000 00000000 c00bcf60 00000000 c0172029 Call Trace: [<c0172029>] Code: 85 c0 74 bf 00 e0 ff ff 21 e7 31 f6 bd 10 00 00 00 31 db >>EIP; c0235cdb <synchronize_tsc_ap+1b/a0> <===== Trace; c0172029 <set_cursor+69/80> Code; c0235cdb <synchronize_tsc_ap+1b/a0> 00000000 <_EIP>: Code; c0235cdb <synchronize_tsc_ap+1b/a0> <===== 0: 85 c0 test %eax,%eax <===== Code; c0235cdd <synchronize_tsc_ap+1d/a0> 2: 74 bf je ffffffc3 <_EIP+0xffffffc3> c0235c9e <synchronize_tsc_bp+1ee/210> Code; c0235cdf <synchronize_tsc_ap+1f/a0> 4: 00 e0 add %ah,%al Code; c0235ce1 <synchronize_tsc_ap+21/a0> 6: ff (bad) Code; c0235ce2 <synchronize_tsc_ap+22/a0> 7: ff 21 jmp *(%ecx) Code; c0235ce4 <synchronize_tsc_ap+24/a0> 9: e7 31 out %eax,$0x31 Code; c0235ce6 <synchronize_tsc_ap+26/a0> b: f6 bd 10 00 00 00 idiv 0x10(%ebp),%al Code; c0235cec <synchronize_tsc_ap+2c/a0> 11: 31 db xor %ebx,%ebx 2 warnings issued. Results may not be reliable. # cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 8 model name : Pentium III (Coppermine) stepping : 6 cpu MHz : 937.557 cache size : 256 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 2 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 mmx fxsr sse bogomips : 1867.77 processor : 1 vendor_id : GenuineIntel cpu family : 6 model : 8 model name : Pentium III (Coppermine) stepping : 6 cpu MHz : 937.557 cache size : 256 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 2 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 mmx fxsr sse bogomips : 1874.32 If this doesn't make someone go "aha!" then I can set up a serial port for debugging and repeat this a few times. Thanks, Paul - 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/