Hello, I've the same bug, with kernel amd64 2xcpu, but with 386 SMP only one cpu. The computer was an ACER L5100 dmidecode partial System Information Manufacturer: Acer Product Name: AL 5100 / VL410 Version: R01-B0 <------ LASTEST BIOS Serial Number: UUID: 00000000-0000-0000-0807-060504030201 Wake-up Type: Power Switch SKU Number: Family: Handle 0x0002, DMI type 2, 14 bytes Base Board Information Manufacturer: Acer Product Name: FRS690L Version: Serial Number: ------------ Processor Information Socket Designation: Socket AM2 Type: Central Processor Family: Athlon 64 X2 Manufacturer: AMD ID: B1 0F 06 00 FF FB 8B 17 Signature: Family 15, Model 107, Stepping 1 Flags: FPU (Floating-point unit on-chip) VME (Virtual mode extension) DE (Debugging extension) PSE (Page size extension) TSC (Time stamp counter) MSR (Model specific registers) PAE (Physical address extension) MCE (Machine check exception) CX8 (CMPXCHG8 instruction supported) APIC (On-chip APIC hardware supported) SEP (Fast system call) MTRR (Memory type range registers) PGE (Page global enable) MCA (Machine check architecture) CMOV (Conditional move instruction supported) PAT (Page attribute table) PSE-36 (36-bit page size extension) CLFSH (CLFLUSH instruction supported) MMX (MMX technology supported) FXSR (Fast floating-point save and restore) SSE (Streaming SIMD extensions) SSE2 (Streaming SIMD extensions 2) HTT (Hyper-threading technology) Version: AMD Athlon(tm) 64 X2 Dual Core Processor 5000+ Voltage: 1.3 V External Clock: 199 MHz Max Speed: 3000 MHz Current Speed: 2587 MHz Status: Populated, Enabled Upgrade: Socket 940 L1 Cache Handle: 0x0008 L2 Cache Handle: 0x0009 L3 Cache Handle: Not Provided Serial Number: Asset Tag: Part Number: Core Count: 2 Core Enabled: 2 Thread Count: 2 Characteristics: 64-bit capable #uname -a Linux XXXXXXXXXX 2.6.22-14-generic #1 SMP Tue Feb 12 07:42:25 UTC 2008 i686 GNU/Linux # cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 15 model : 107 model name : AMD Athlon(tm) 64 X2 Dual Core Processor 5000+ stepping : 1 cpu MHz : 2200.000 cache size : 512 KB physical id : 0 siblings : 1 core id : 0 cpu cores : 1 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt rdtscp lm 3dnowext 3dnow pni cx16 lahf_lm cmp_legacy svm extapic cr8legacy 3dnowprefetch ts fid vid ttp tm stc 100mhzsteps bogomips : 4523.17 clflush size : 64 partial dmesg [ 0.000000] BIOS-provided physical RAM map: [ 0.000000] BIOS-e820: 0000000000000000 - 000000000009f400 (usable) [ 0.000000] BIOS-e820: 000000000009f400 - 00000000000a0000 (reserved) [ 0.000000] BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved) [ 0.000000] BIOS-e820: 0000000000100000 - 0000000077fe0000 (usable) [ 0.000000] BIOS-e820: 0000000077fe0000 - 0000000077fe3000 (ACPI NVS) [ 0.000000] BIOS-e820: 0000000077fe3000 - 0000000077ff0000 (ACPI data) [ 0.000000] BIOS-e820: 0000000077ff0000 - 0000000078000000 (reserved) [ 0.000000] BIOS-e820: 00000000e0000000 - 00000000f0000000 (reserved) [ 0.000000] BIOS-e820: 00000000fec00000 - 0000000100000000 (reserved) [ 0.000000] 1023MB HIGHMEM available. [ 0.000000] 896MB LOWMEM available. [ 0.000000] found SMP MP-table at 000f3930 [ 0.000000] Entering add_active_range(0, 0, 491488) 0 entries of 256 used [ 0.000000] Zone PFN ranges: [ 0.000000] DMA 0 -> 4096 [ 0.000000] Normal 4096 -> 229376 [ 0.000000] HighMem 229376 -> 491488 [ 0.000000] early_node_map[1] active PFN ranges [ 0.000000] 0: 0 -> 491488 [ 0.000000] On node 0 totalpages: 491488 [ 0.000000] DMA zone: 32 pages used for memmap [ 0.000000] DMA zone: 0 pages reserved [ 0.000000] DMA zone: 4064 pages, LIFO batch:0 [ 0.000000] Normal zone: 1760 pages used for memmap [ 0.000000] Normal zone: 223520 pages, LIFO batch:31 [ 0.000000] HighMem zone: 2047 pages used for memmap [ 0.000000] HighMem zone: 260065 pages, LIFO batch:31 [ 0.000000] DMI 2.5 present. [ 0.000000] ACPI: RSDP signature @ 0xC00F7A30 checksum 0 [ 0.000000] ACPI: RSDP 000F7A30, 0024 (r2 ACRSYS) [ 0.000000] ACPI: RSDT 77FE3000, 003C (r1 ACRSYS ACRPRDCT 42302E31 AWRD 0) [ 0.000000] ACPI: FACP 77FE3080, 0074 (r1 ACRSYS ACRPRDCT 42302E31 AWRD 0) [ 0.000000] ACPI: DSDT 77FE3100, 411D (r1 ACRSYS ACRPRDCT 1000 MSFT 3000000) [ 0.000000] ACPI: FACS 77FE0000, 0040 [ 0.000000] ACPI: SSDT 77FE72C0, 028A (r1 PTLTD POWERNOW 1 LTP 1) [ 0.000000] ACPI: HPET 77FE7580, 0038 (r1 ACRSYS ACRPRDCT 42302E31 AWRD 98) [ 0.000000] ACPI: SLIC 77FE75C0, 0176 (r1 ACRSYS ACRPRDCT 42302E31 AWRD 20) [ 0.000000] ACPI: MCFG 77FE7740, 003C (r1 ACRSYS ACRPRDCT 42302E31 AWRD 0) [ 0.000000] ACPI: APIC 77FE7240, 0068 (r1 ACRSYS ACRPRDCT 42302E31 AWRD 0) [ 0.000000] ATI board detected. Disabling timer routing over 8254. [ 0.000000] ACPI: PM-Timer IO Port: 0x4008 [ 0.000000] ACPI: Local APIC address 0xfee00000 [ 0.000000] ACPI: LAPIC (acpi_id[0x00] lapic_id[0x00] enabled) [ 0.000000] Processor #0 15:11 APIC version 16 [ 0.000000] ACPI: LAPIC (acpi_id[0x01] lapic_id[0x01] enabled) [ 0.000000] Processor #1 15:11 APIC version 16 [ 0.000000] ACPI: LAPIC_NMI (acpi_id[0x00] high edge lint[0x1]) [ 0.000000] ACPI: LAPIC_NMI (acpi_id[0x01] high edge lint[0x1]) [ 0.000000] ACPI: IOAPIC (id[0x02] address[0xfec00000] gsi_base[0]) [ 0.000000] IOAPIC[0]: apic_id 2, version 33, address 0xfec00000, GSI 0-23 [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl) [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 low level) [ 0.000000] ACPI: IRQ0 used by override. [ 0.000000] ACPI: IRQ2 used by override. [ 0.000000] ACPI: IRQ9 used by override. [ 0.000000] Enabling APIC mode: Flat. Using 1 I/O APICs [ 0.000000] ACPI: HPET id: 0x8300 base: 0xfed00000 [ 0.000000] Using ACPI (MADT) for SMP configuration information [ 0.000000] Allocating PCI resources starting at 80000000 (gap: 78000000:68000000) [ 0.000000] Built 1 zonelists. Total pages: 487649 [ 0.000000] Kernel command line: root=UUID=7247ac1d-923e-4aab-84a8-3708e0c7c994 ro quiet splash [ 0.000000] mapped APIC to ffffd000 (fee00000) [ 0.000000] mapped IOAPIC to ffffc000 (fec00000) [ 0.000000] Enabling fast FPU save and restore... done. [ 0.000000] Enabling unmasked SIMD FPU exception support... done. [ 0.000000] Initializing CPU#0 [ 0.000000] PID hash table entries: 4096 (order: 12, 16384 bytes) [ 0.000000] Detected 2593.743 MHz processor. [ 0.000000] Console: colour VGA+ 80x25 [ 0.000000] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes) [ 0.000000] Inode-cache hash table entries: 65536 (order: 6, 262144 bytes) [ 0.000000] Memory: 1937924k/1965952k available (2015k kernel code, 26780k reserved, 915k data, 364k init, 1048448k highmem) [ 0.000000] virtual kernel memory layout: [ 0.000000] fixmap : 0xfff4d000 - 0xfffff000 ( 712 kB) [ 0.000000] pkmap : 0xff800000 - 0xffc00000 (4096 kB) [ 0.000000] vmalloc : 0xf8800000 - 0xff7fe000 ( 111 MB) [ 0.000000] lowmem : 0xc0000000 - 0xf8000000 ( 896 MB) [ 0.000000] .init : 0xc03e3000 - 0xc043e000 ( 364 kB) [ 0.000000] .data : 0xc02f7e86 - 0xc03dce84 ( 915 kB) [ 0.000000] .text : 0xc0100000 - 0xc02f7e86 (2015 kB) [ 0.000000] Checking if this processor honours the WP bit even in supervisor mode... Ok. [ 0.000000] SLUB: Genslabs=22, HWalign=64, Order=0-1, MinObjects=4, CPUs=2, Nodes=1 [ 0.000000] hpet0: at MMIO 0xfed00000, IRQs 2, 8, 0, 0 [ 0.000000] hpet0: 4 32-bit timers, 14318180 Hz [ 0.084000] Calibrating delay using timer specific routine.. 5345.56 BogoMIPS (lpj=10691132) [ 0.084000] Security Framework v1.0.0 initialized [ 0.084000] SELinux: Disabled at boot. [ 0.084000] Mount-cache hash table entries: 512 [ 0.084000] CPU: After generic identify, caps: 178bfbff ebd3fbff 00000000 00000000 00002001 00000000 0000011f [ 0.084000] CPU: L1 I Cache: 64K (64 bytes/line), D cache 64K (64 bytes/line) [ 0.084000] CPU: L2 Cache: 512K (64 bytes/line) [ 0.084000] CPU 0(2) -> Core 0 [ 0.084000] CPU: After all inits, caps: 178bfbff ebd3fbff 00000000 00000410 00002001 00000000 0000011f [ 0.084000] Compat vDSO mapped to ffffe000. [ 0.084000] Checking 'hlt' instruction... OK. [ 0.100000] SMP alternatives: switching to UP code [ 0.100000] Early unpacking initramfs... done [ 0.328000] ACPI: Core revision 20070126 [ 0.328000] ACPI: Looking for DSDT in initramfs... error, file /DSDT.aml not found. [ 0.336000] CPU0: AMD Athlon(tm) 64 X2 Dual Core Processor 5000+ stepping 01 [ 0.336000] SMP alternatives: switching to SMP code [ 0.336000] Booting processor 1/1 eip 3000 [ 5.468000] Not responding. [ 5.468000] Inquiring remote APIC #1... [ 5.468000] ... APIC #1 ID: 1000000 [ 5.468000] ... APIC #1 VERSION: 80050010 [ 5.468000] ... APIC #1 SPIV: ff [ 5.468000] CPU #1 not responding - cannot use it. [ 5.468000] Total of 1 processors activated (5345.56 BogoMIPS). [ 5.468000] ENABLING IO-APIC IRQs [ 5.468000] ..TIMER: vector=0x31 apic1=0 pin1=2 apic2=-1 pin2=-1