我有 Ubuntu 18.04
# lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 18.04.1 LTS
Release: 18.04
Codename: bionic
# uname -a
Linux kb 4.15.0-34-generic #37-Ubuntu SMP Mon Aug 27 15:21:48 UTC 2018
x86_64 x86_64 x86_64 GNU/Linux
它安装在超微 X10SDV-4C-TLN2F。
我只能看到 8 个 CPU 中的一个。当我将这台机器从 Debian 移到 Ubuntu 时，这可以正常工作，在 Debian 上，我可以看到同一硬件中的 8 个 CPU。唯一的区别是，当时操作系统在 ZFS 硬盘上（这不是一个好主意，但对我来说很好...），现在操作系统在新的 SSD 上。
# lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
CPU(s): 1
On-line CPU(s) list: 0
Thread(s) per core: 1
Core(s) per socket: 1
Socket(s): 1
NUMA node(s): 1
Vendor ID: GenuineIntel
CPU family: 6
Model: 86
Model name: Intel(R) Xeon(R) CPU D-1518 @ 2.20GHz
Stepping: 3
CPU MHz: 800.134
CPU max MHz: 2200,0000
CPU min MHz: 800,0000
BogoMIPS: 4399.64
Virtualization: VT-x
L1d cache: 32K
L1i cache: 32K
L2 cache: 256K
L3 cache: 6144K
NUMA node0 CPU(s): 0
Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall
nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl
xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl
vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2
x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm
abm 3dnowprefetch cpuid_fault epb cat_l3 cdp_l3 invpcid_single pti
intel_ppin ssbd ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid
fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm rdt_a
rdseed adx smap intel_pt xsaveopt cqm_llc cqm_occup_llc cqm_mbm_total
cqm_mbm_local dtherm arat pln pts flush_l1d
我在 dmesg 中收到以下内容：
[ 0.000000] Linux version 4.15.0-34-generic (buildd@lgw01-amd64-047) (gcc version 7.3.0 (Ubuntu 7.3.0-16ubuntu3)) #37-Ubuntu SMP Mon Aug 27 15:21:48 UTC 2018 (Ubuntu 4.15.0-34.37-generic 4.15.18)
[ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-4.15.0-34-generic root=UUID=5c533343-893f-4dbd-8dbe-2bf1eedeb960 ro quiet nr_cpus=8 splash vt.handoff=1
[ 0.000000] KERNEL supported cpus:
[ 0.000000] Intel GenuineIntel
[ 0.000000] AMD AuthenticAMD
[ 0.000000] Centaur CentaurHauls
[ 0.000000] x86/fpu: Supporting XSAVE feature 0x001: 'x87 floating point registers'
[ 0.000000] x86/fpu: Supporting XSAVE feature 0x002: 'SSE registers'
[ 0.000000] x86/fpu: Supporting XSAVE feature 0x004: 'AVX registers'
[ 0.000000] x86/fpu: xstate_offset[2]: 576, xstate_sizes[2]: 256
[ 0.000000] x86/fpu: Enabled xstate features 0x7, context size is 832 bytes, using 'standard' format.
[ 0.000000] e820: BIOS-provided physical RAM map:
[ 0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009ffff] usable
[ 0.000000] BIOS-e820: [mem 0x0000000000100000-0x00000000796ebfff] usable
[ 0.000000] BIOS-e820: [mem 0x00000000796ec000-0x00000000798bafff] reserved
[ 0.000000] BIOS-e820: [mem 0x00000000798bb000-0x0000000079a26fff] usable
[ 0.000000] BIOS-e820: [mem 0x0000000079a27000-0x0000000079e57fff] ACPI NVS
[ 0.000000] BIOS-e820: [mem 0x0000000079e58000-0x000000007bd4cfff] reserved
[ 0.000000] BIOS-e820: [mem 0x000000007bd4d000-0x000000007bdb0fff] type 20
[ 0.000000] BIOS-e820: [mem 0x000000007bdb1000-0x000000007bdb1fff] usable
[ 0.000000] BIOS-e820: [mem 0x000000007bdb2000-0x000000007be37fff] reserved
[ 0.000000] BIOS-e820: [mem 0x000000007be38000-0x000000007bffffff] usable
[ 0.000000] BIOS-e820: [mem 0x0000000080000000-0x000000008fffffff] reserved
[ 0.000000] BIOS-e820: [mem 0x00000000fed1c000-0x00000000fed1ffff] reserved
[ 0.000000] BIOS-e820: [mem 0x00000000ff000000-0x00000000ffffffff] reserved
[ 0.000000] NX (Execute Disable) protection: active
[ 0.000000] efi: EFI v2.40 by American Megatrends
[ 0.000000] efi: ACPI=0x79ae7000 ACPI 2.0=0x79ae7000 ESRT=0x7bb14e18
[ 0.000000] secureboot: Secure boot could not be determined (mode 0)
[ 0.000000] DMI not present or invalid.
[ 0.000000] e820: update [mem 0x00000000-0x00000fff] usable ==> reserved
[ 0.000000] e820: remove [mem 0x000a0000-0x000fffff] usable
[ 0.000000] e820: last_pfn = 0x7c000 max_arch_pfn = 0x400000000
[ 0.000000] MTRR default type: write-back
[ 0.000000] MTRR fixed ranges enabled:
[ 0.000000] 00000-9FFFF write-back
[ 0.000000] A0000-BFFFF uncachable
[ 0.000000] C0000-FFFFF write-protect
[ 0.000000] MTRR variable ranges enabled:
[ 0.000000] 0 base 000080000000 mask 3FFF80000000 uncachable
[ 0.000000] 1 base 380000000000 mask 3FC000000000 uncachable
[ 0.000000] 2 base 0000E0000000 mask 3FFFF0000000 write-through
[ 0.000000] 3 base 0000F0000000 mask 3FFFFE000000 write-through
[ 0.000000] 4 base 0000F2000000 mask 3FFFFFC00000 write-through
[ 0.000000] 5 base 0000F2400000 mask 3FFFFFE00000 write-through
[ 0.000000] 6 base 0000F2600000 mask 3FFFFFF00000 write-through
[ 0.000000] 7 disabled
[ 0.000000] 8 disabled
[ 0.000000] 9 disabled
[ 0.000000] x86/PAT: Configuration [0-7]: WB WC UC- UC WB WP UC- WT
[ 0.000000] esrt: Reserving ESRT space from 0x000000007bb14e18 to 0x000000007bb14e50.
[ 0.000000] Scanning 1 areas for low memory corruption
[ 0.000000] Base memory trampoline at [ (ptrval)] 96000 size 24576
[ 0.000000] Using GB pages for direct mapping
[ 0.000000] BRK [0x4753e000, 0x4753efff] PGTABLE
[ 0.000000] BRK [0x4753f000, 0x4753ffff] PGTABLE
[ 0.000000] BRK [0x47540000, 0x47540fff] PGTABLE
[ 0.000000] BRK [0x47541000, 0x47541fff] PGTABLE
[ 0.000000] BRK [0x47542000, 0x47542fff] PGTABLE
[ 0.000000] BRK [0x47543000, 0x47543fff] PGTABLE
[ 0.000000] BRK [0x47544000, 0x47544fff] PGTABLE
[ 0.000000] BRK [0x47545000, 0x47545fff] PGTABLE
[ 0.000000] BRK [0x47546000, 0x47546fff] PGTABLE
[ 0.000000] BRK [0x47547000, 0x47547fff] PGTABLE
[ 0.000000] RAMDISK: [mem 0x1da3a000-0x21765fff]
[ 0.000000] ACPI: Early table checksum verification disabled
[ 0.000000] ACPI: RSDP 0x0000000079AE7000 000024 (v02 SUPERM)
[ 0.000000] ACPI: XSDT 0x0000000079AE7080 00007C (v01 SUPERM SMCI--MB 01072009 AMI 00010013)
[ 0.000000] ACPI: FACP 0x0000000079AFF8A8 00010C (v05 SUPERM SMCI--MB 01072009 AMI 00010013)
[ 0.000000] ACPI: DSDT 0x0000000079AE7190 018716 (v02 SUPERM SMCI--MB 01072009 INTL 20091013)
[ 0.000000] ACPI: FACS 0x0000000079E56F80 000040
[ 0.000000] ACPI: APIC 0x0000000079AFF9B8 00004C (v03 SUPERM SMCI--MB 01072009 AMI 00010013)
[ 0.000000] ACPI: FPDT 0x0000000079AFFA08 000044 (v01 SUPERM SMCI--MB 01072009 AMI 00010013)
[ 0.000000] ACPI: FIDT 0x0000000079AFFA50 00009C (v01 SUPERM SMCI--MB 01072009 AMI 00010013)
[ 0.000000] ACPI: SPMI 0x0000000079AFFAF0 000041 (v05 SUPERM SMCI--MB 00000000 AMI. 00000000)
[ 0.000000] ACPI: MCFG 0x0000000079AFFB38 00003C (v01 SUPERM SMCI--MB 01072009 MSFT 00000097)
[ 0.000000] ACPI: UEFI 0x0000000079AFFB78 000042 (v01 00000000 00000000)
[ 0.000000] ACPI: DBG2 0x0000000079AFFBC0 000072 (v00 SUPERM SMCI--MB 00000000 INTL 20091013)
[ 0.000000] ACPI: HPET 0x0000000079AFFC38 000038 (v01 SUPERM SMCI--MB 00000001 INTL 20091013)
[ 0.000000] ACPI: WDDT 0x0000000079AFFC70 000040 (v01 SUPERM SMCI--MB 00000000 INTL 20091013)
[ 0.000000] ACPI: SSDT 0x0000000079AFFCB0 00EDCB (v01 AMI PmMgt 00000001 INTL 20120913)
[ 0.000000] ACPI: Local APIC address 0xfee00000
[ 0.000000] No NUMA configuration found
[ 0.000000] Faking a node at [mem 0x0000000000000000-0x000000007bffffff]
[ 0.000000] NODE_DATA(0) allocated [mem 0x799fc000-0x79a26fff]
[ 0.000000] tsc: Fast TSC calibration using PIT
[ 0.000000] Zone ranges:
[ 0.000000] DMA [mem 0x0000000000001000-0x0000000000ffffff]
[ 0.000000] DMA32 [mem 0x0000000001000000-0x000000007bffffff]
[ 0.000000] Normal empty
[ 0.000000] Device empty
[ 0.000000] Movable zone start for each node
[ 0.000000] Early memory node ranges
[ 0.000000] node 0: [mem 0x0000000000001000-0x000000000009ffff]
[ 0.000000] node 0: [mem 0x0000000000100000-0x00000000796ebfff]
[ 0.000000] node 0: [mem 0x00000000798bb000-0x0000000079a26fff]
[ 0.000000] node 0: [mem 0x000000007bdb1000-0x000000007bdb1fff]
[ 0.000000] node 0: [mem 0x000000007be38000-0x000000007bffffff]
[ 0.000000] Initmem setup node 0 [mem 0x0000000000001000-0x000000007bffffff]
[ 0.000000] On node 0 totalpages: 498112
[ 0.000000] DMA zone: 64 pages used for memmap
[ 0.000000] DMA zone: 27 pages reserved
[ 0.000000] DMA zone: 3999 pages, LIFO batch:0
[ 0.000000] DMA32 zone: 7872 pages used for memmap
[ 0.000000] DMA32 zone: 494113 pages, LIFO batch:31
[ 0.000000] Reserved but unavailable: 98 pages
[ 0.000000] ACPI: PM-Timer IO Port: 0x408
[ 0.000000] ACPI: Local APIC address 0xfee00000
[ 0.000000] ACPI: No LAPIC entries present
[ 0.000000] Using ACPI for processor (LAPIC) configuration information
[ 0.000000] ACPI: HPET id: 0x8086a701 base: 0xfed00000
[ 0.000000] smpboot: Boot CPU (id 0) not listed by BIOS
[ 0.000000] smpboot: Allowing 1 CPUs, 0 hotplug CPUs
[ 0.000000] PM: Registered nosave memory: [mem 0x00000000-0x00000fff]
[ 0.000000] PM: Registered nosave memory: [mem 0x000a0000-0x000fffff]
[ 0.000000] PM: Registered nosave memory: [mem 0x796ec000-0x798bafff]
[ 0.000000] PM: Registered nosave memory: [mem 0x79a27000-0x79e57fff]
[ 0.000000] PM: Registered nosave memory: [mem 0x79e58000-0x7bd4cfff]
[ 0.000000] PM: Registered nosave memory: [mem 0x7bd4d000-0x7bdb0fff]
[ 0.000000] PM: Registered nosave memory: [mem 0x7bdb2000-0x7be37fff]
[ 0.000000] e820: [mem 0x90000000-0xfed1bfff] available for PCI devices
[ 0.000000] Booting paravirtualized kernel on bare hardware
[ 0.000000] clocksource: refined-jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645519600211568 ns
[ 0.000000] random: get_random_bytes called from start_kernel+0x99/0x4fd with crng_init=0
[ 0.000000] setup_percpu: NR_CPUS:8192 nr_cpumask_bits:1 nr_cpu_ids:1 nr_node_ids:1
[ 0.000000] percpu: Embedded 46 pages/cpu @ (ptrval) s151552 r8192 d28672 u2097152
[ 0.000000] pcpu-alloc: s151552 r8192 d28672 u2097152 alloc=1*2097152
[ 0.000000] pcpu-alloc: [0] 0
[ 0.000000] Built 1 zonelists, mobility grouping on. Total pages: 490149
[ 0.000000] Policy zone: DMA32
[ 0.000000] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-4.15.0-34-generic root=UUID=5c533343-893f-4dbd-8dbe-2bf1eedeb960 ro quiet nr_cpus=8 splash vt.handoff=1
[ 0.000000] Calgary: detecting Calgary via BIOS EBDA area
[ 0.000000] Calgary: Unable to locate Rio Grande table in EBDA - bailing!
[ 0.000000] Memory: 1493264K/1992448K available (12300K kernel code, 2471K rwdata, 4244K rodata, 2408K init, 2416K bss, 499184K reserved, 0K cma-reserved)
[ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
[ 0.000000] Kernel/User page tables isolation: enabled
[ 0.000000] ftrace: allocating 39147 entries in 153 pages
[ 0.000000] Hierarchical RCU implementation.
[ 0.000000] RCU restricting CPUs from NR_CPUS=8192 to nr_cpu_ids=1.
[ 0.000000] Tasks RCU enabled.
[ 0.000000] RCU: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1
[ 0.000000] NR_IRQS: 524544, nr_irqs: 32, preallocated irqs: 16
[ 0.000000] vt handoff: transparent VT on vt#1
[ 0.000000] Console: colour dummy device 80x25
[ 0.000000] console [tty0] enabled
[ 0.000000] ACPI: Core revision 20170831
[ 0.000000] ACPI: 2 ACPI AML tables successfully acquired and loaded
[ 0.000000] ACPI: setting ELCR to 0200 (from 0000)
[ 0.000000] clocksource: hpet: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 133484882848 ns
[ 0.000000] hpet clockevent registered
[ 0.000000] APIC: Switch to symmetric I/O mode setup
[ 0.000000] x2apic: IRQ remapping doesn't support X2APIC mode
[ 0.000000] tsc: Fast TSC calibration using PIT
[ 0.004000] tsc: Detected 2199.822 MHz processor
[ 0.004000] Calibrating delay loop (skipped), value calculated using timer frequency.. 4399.64 BogoMIPS (lpj=8799288)
[ 0.004000] pid_max: default: 32768 minimum: 301
[ 0.004000] Security Framework initialized
[ 0.004000] Yama: becoming mindful.
[ 0.004000] AppArmor: AppArmor initialized
[ 0.004000] Dentry cache hash table entries: 262144 (order: 9, 2097152 bytes)
[ 0.004000] Inode-cache hash table entries: 131072 (order: 8, 1048576 bytes)
[ 0.004000] Mount-cache hash table entries: 4096 (order: 3, 32768 bytes)
[ 0.004000] Mountpoint-cache hash table entries: 4096 (order: 3, 32768 bytes)
[ 0.004000] ENERGY_PERF_BIAS: Set to 'normal', was 'performance'
[ 0.004000] ENERGY_PERF_BIAS: View and update with x86_energy_perf_policy(8)
[ 0.004000] mce: CPU supports 22 MCE banks
[ 0.004000] CPU0: Thermal monitoring enabled (TM1)
[ 0.004000] process: using mwait in idle threads
[ 0.004000] Last level iTLB entries: 4KB 64, 2MB 8, 4MB 8
[ 0.004000] Last level dTLB entries: 4KB 64, 2MB 0, 4MB 0, 1GB 4
[ 0.004000] Spectre V2 : Mitigation: Full generic retpoline
[ 0.004000] Spectre V2 : Spectre v2 mitigation: Enabling Indirect Branch Prediction Barrier
[ 0.004000] Spectre V2 : Enabling Restricted Speculation for firmware calls
[ 0.004000] Speculative Store Bypass: Mitigation: Speculative Store Bypass disabled via prctl and seccomp
[ 0.030081] Freeing SMP alternatives memory: 36K
[ 0.053603] TSC deadline timer enabled
[ 0.053607] smpboot: CPU0: Intel(R) Xeon(R) CPU D-1518 @ 2.20GHz (family: 0x6, model: 0x56, stepping: 0x3)
[ 0.053754] Performance Events: PEBS fmt2+, Broadwell events, 16-deep LBR, full-width counters, Intel PMU driver.
[ 0.053813] ... version: 3
[ 0.053815] ... bit width: 48
[ 0.053816] ... generic registers: 4
[ 0.053818] ... value mask: 0000ffffffffffff
[ 0.053820] ... max period: 00007fffffffffff
[ 0.053821] ... fixed-purpose events: 3
[ 0.053823] ... event mask: 000000070000000f
[ 0.053895] Hierarchical SRCU implementation.
[ 0.055986] NMI watchdog: Enabled. Permanently consumes one hw-PMU counter.
[ 0.056000] smp: Bringing up secondary CPUs ...
[ 0.056000] smp: Brought up 1 node, 1 CPU
[ 0.056000] smpboot: Max logical packages: 1
[ 0.056000] smpboot: Total of 1 processors activated (4399.64 BogoMIPS)
[ 0.056363] devtmpfs: initialized
[ 0.056492] x86/mm: Memory block size: 128MB
[ 0.057069] evm: security.selinux
[ 0.057071] evm: security.SMACK64
[ 0.057072] evm: security.SMACK64EXEC
[ 0.057073] evm: security.SMACK64TRANSMUTE
[ 0.057075] evm: security.SMACK64MMAP
[ 0.057076] evm: security.apparmor
[ 0.057077] evm: security.ima
[ 0.057079] evm: security.capability
[ 0.057204] PM: Registering ACPI NVS region [mem 0x79a27000-0x79e57fff] (4395008 bytes)
[ 0.057477] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
[ 0.057487] futex hash table entries: 256 (order: 2, 16384 bytes)
[ 0.057563] pinctrl core: initialized pinctrl subsystem
[ 0.057761] RTC time: 22:13:23, date: 09/20/18
[ 0.057977] NET: Registered protocol family 16
[ 0.058175] audit: initializing netlink subsys (disabled)
[ 0.058476] cpuidle: using governor ladder
[ 0.058479] cpuidle: using governor menu
[ 0.058578] ACPI: bus type PCI registered
[ 0.058581] acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5
[ 0.058646] PCI: MMCONFIG for domain 0000 [bus 00-ff] at [mem 0x80000000-0x8fffffff] (base 0x80000000)
[ 0.058652] PCI: MMCONFIG at [mem 0x80000000-0x8fffffff] reserved in E820
[ 0.058688] PCI: Using configuration type 1 for base access
[ 0.061750] audit: type=2000 audit(1537481603.056:1): state=initialized audit_enabled=0 res=1
[ 0.061891] HugeTLB registered 1.00 GiB page size, pre-allocated 0 pages
[ 0.061894] HugeTLB registered 2.00 MiB page size, pre-allocated 0 pages
[ 0.062303] ACPI: Added _OSI(Module Device)
[ 0.062306] ACPI: Added _OSI(Processor Device)
[ 0.062308] ACPI: Added _OSI(3.0 _SCP Extensions)
[ 0.062310] ACPI: Added _OSI(Processor Aggregator Device)
[ 0.062312] ACPI: Added _OSI(Linux-Dell-Video)
[ 0.062315] ACPI: Added _OSI(Linux-Lenovo-NV-HDMI-Audio)
[ 0.219316] ACPI: Interpreter enabled
[ 0.219352] ACPI: (supports S0 S4 S5)
[ 0.219355] ACPI: Using PIC for interrupt routing
[ 0.219428] PCI: Using host bridge windows from ACPI; if necessary, use "pci=nocrs" and report a bug
[ 0.220407] ACPI: Enabled 5 GPEs in block 00 to 3F
[ 0.319963] ACPI: PCI Root Bridge [UNC0] (domain 0000 [bus ff])
[ 0.319975] acpi PNP0A03:03: _OSC: OS supports [ExtendedConfig ASPM ClockPM Segments MSI]
[ 0.321903] acpi PNP0A03:03: _OSC: OS now controls [PCIeHotplug PME AER PCIeCapability]
[ 0.322026] PCI host bridge to bus 0000:ff
[ 0.322032] pci_bus 0000:ff: root bus resource [bus ff]
[ 0.322060] pci 0000:ff:0b.0: [8086:6f81] type 00 class 0x088000
[ 0.322193] pci 0000:ff:0b.1: [8086:6f36] type 00 class 0x110100
[ 0.322307] pci 0000:ff:0b.2: [8086:6f37] type 00 class 0x110100
[ 0.322417] pci 0000:ff:0b.3: [8086:6f76] type 00 class 0x088000
[ 0.322533] pci 0000:ff:0c.0: [8086:6fe0] type 00 class 0x088000
[ 0.322644] pci 0000:ff:0c.1: [8086:6fe1] type 00 class 0x088000
[ 0.322752] pci 0000:ff:0c.2: [8086:6fe2] type 00 class 0x088000
[ 0.322859] pci 0000:ff:0c.3: [8086:6fe3] type 00 class 0x088000
[ 0.322976] pci 0000:ff:0f.0: [8086:6ff8] type 00 class 0x088000
[ 0.323086] pci 0000:ff:0f.4: [8086:6ffc] type 00 class 0x088000
[ 0.323193] pci 0000:ff:0f.5: [8086:6ffd] type 00 class 0x088000
[ 0.323304] pci 0000:ff:0f.6: [8086:6ffe] type 00 class 0x088000
[ 0.323416] pci 0000:ff:10.0: [8086:6f1d] type 00 class 0x088000
[ 0.323525] pci 0000:ff:10.1: [8086:6f34] type 00 class 0x110100
[ 0.323636] pci 0000:ff:10.5: [8086:6f1e] type 00 class 0x088000
[ 0.323746] pci 0000:ff:10.6: [8086:6f7d] type 00 class 0x110100
[ 0.323853] pci 0000:ff:10.7: [8086:6f1f] type 00 class 0x088000
[ 0.323964] pci 0000:ff:12.0: [8086:6fa0] type 00 class 0x088000
[ 0.324045] pci 0000:ff:12.1: [8086:6f30] type 00 class 0x110100
[ 0.324168] pci 0000:ff:13.0: [8086:6fa8] type 00 class 0x088000
[ 0.324288] pci 0000:ff:13.1: [8086:6f71] type 00 class 0x088000
[ 0.324406] pci 0000:ff:13.2: [8086:6faa] type 00 class 0x088000
[ 0.324523] pci 0000:ff:13.3: [8086:6fab] type 00 class 0x088000
[ 0.324643] pci 0000:ff:13.4: [8086:6fac] type 00 class 0x088000
[ 0.324761] pci 0000:ff:13.5: [8086:6fad] type 00 class 0x088000
[ 0.324877] pci 0000:ff:13.6: [8086:6fae] type 00 class 0x088000
[ 0.324993] pci 0000:ff:13.7: [8086:6faf] type 00 class 0x088000
[ 0.325104] pci 0000:ff:14.0: [8086:6fb0] type 00 class 0x088000
[ 0.325224] pci 0000:ff:14.1: [8086:6fb1] type 00 class 0x088000
[ 0.325346] pci 0000:ff:14.2: [8086:6fb2] type 00 class 0x088000
[ 0.325464] pci 0000:ff:14.3: [8086:6fb3] type 00 class 0x088000
[ 0.325581] pci 0000:ff:14.4: [8086:6fbc] type 00 class 0x088000
[ 0.325693] pci 0000:ff:14.5: [8086:6fbd] type 00 class 0x088000
[ 0.325803] pci 0000:ff:14.6: [8086:6fbe] type 00 class 0x088000
[ 0.325913] pci 0000:ff:14.7: [8086:6fbf] type 00 class 0x088000
[ 0.326027] pci 0000:ff:15.0: [8086:6fb4] type 00 class 0x088000
[ 0.326148] pci 0000:ff:15.1: [8086:6fb5] type 00 class 0x088000
[ 0.326267] pci 0000:ff:15.2: [8086:6fb6] type 00 class 0x088000
[ 0.326385] pci 0000:ff:15.3: [8086:6fb7] type 00 class 0x088000
[ 0.326526] pci 0000:ff:1e.0: [8086:6f98] type 00 class 0x088000
[ 0.326635] pci 0000:ff:1e.1: [8086:6f99] type 00 class 0x088000
[ 0.326750] pci 0000:ff:1e.2: [8086:6f9a] type 00 class 0x088000
[ 0.326860] pci 0000:ff:1e.3: [8086:6fc0] type 00 class 0x088000
[ 0.326941] pci 0000:ff:1e.4: [8086:6f9c] type 00 class 0x088000
[ 0.327059] pci 0000:ff:1f.0: [8086:6f88] type 00 class 0x088000
[ 0.327171] pci 0000:ff:1f.2: [8086:6f8a] type 00 class 0x088000
[ 0.329861] APIC: NR_CPUS/possible_cpus limit of 1 reached. Processor 1/0x2 ignored.
[ 0.329862] ACPI: Unable to map lapic to logical cpu number
[ 0.331143] APIC: NR_CPUS/possible_cpus limit of 1 reached. Processor 2/0x4 ignored.
[ 0.331144] ACPI: Unable to map lapic to logical cpu number
[ 0.332446] APIC: NR_CPUS/possible_cpus limit of 1 reached. Processor 3/0x6 ignored.
[ 0.332448] ACPI: Unable to map lapic to logical cpu number
[ 0.333728] APIC: NR_CPUS/possible_cpus limit of 1 reached. Processor 4/0x1 ignored.
[ 0.333729] ACPI: Unable to map lapic to logical cpu number
[ 0.335008] APIC: NR_CPUS/possible_cpus limit of 1 reached. Processor 5/0x3 ignored.
[ 0.335009] ACPI: Unable to map lapic to logical cpu number
[ 0.336311] APIC: NR_CPUS/possible_cpus limit of 1 reached. Processor 6/0x5 ignored.
[ 0.336312] ACPI: Unable to map lapic to logical cpu number
[ 0.337590] APIC: NR_CPUS/possible_cpus limit of 1 reached. Processor 7/0x7 ignored.
[ 0.337591] ACPI: Unable to map lapic to logical cpu number
[ 0.347574] ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-fe])
[ 0.347586] acpi PNP0A08:00: _OSC: OS supports [ExtendedConfig ASPM ClockPM Segments MSI]
[ 0.349465] acpi PNP0A08:00: _OSC: OS now controls [PCIeHotplug PME AER PCIeCapability]
[ 0.350433] PCI host bridge to bus 0000:00
[ 0.350441] pci_bus 0000:00: root bus resource [io 0x0000-0x0cf7 window]
[ 0.350445] pci_bus 0000:00: root bus resource [io 0x1000-0xffff window]
[ 0.350449] pci_bus 0000:00: root bus resource [mem 0x000a0000-0x000bffff window]
[ 0.350453] pci_bus 0000:00: root bus resource [mem 0x90000000-0xfbffbfff window]
[ 0.350458] pci_bus 0000:00: root bus resource [bus 00-fe]
...
请注意包含以下内容的行APIC: NR_CPUS/possible_cpus limit of 1 reached，它们很好地描述了（我猜）问题。
我的/etc/default/grub：
# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
# info -f grub -n 'Simple configuration'
GRUB_DEFAULT=0
GRUB_TIMEOUT_STYLE=hidden
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX=""
# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"
# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console
# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via
VBE
# you can see them in real GRUB with the command `vbeinfo'
#GRUB_GFXMODE=640x480
# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to
Linux
#GRUB_DISABLE_LINUX_UUID=true
# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY="true"
# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"
我已经尝试过的：
- 包括
nr_cpus=8GRUB_CMDLINE_LINUX_DEFAULT - 检查 BIOS 中是否启用了 ACPI 以及与 BIOS 相关的任何其他可能性。
如果需要，我还可以分享其他日志（例如 /var/log/kern.log）。
我将非常感谢任何能够帮助我找回丢失的 7 个 CPU 的帮助。
感谢并致以亲切的问候，
拉尼
答案1
奇怪的是，上述行为仅在从 UEFI 启动时才会发生。使用传统模式时，所有 CPU 都可用。
遗憾的是，Ubuntu 安装程序没有提供以传统模式安装 grub2 的选项 - 这在遇到此类问题时可以省去很多麻烦。但是，有很多关于如何做到这一点的文档。例如https://help.ubuntu.com/community/UEFI#Converting_Ubuntu_into_Legacy_mode非常棒的一个。
答案2
提及https://forums.gentoo.org/viewtopic-p-7849822.html?sid=5d0d8389156f1ce476f2c3d7ebdbdb39，除非位于 EFI 分区的根目录中，否则 BIOS 会出现问题 *.efi 文件。
此外，当您在 BIOS 中选择“启动选项”时，即使您指定了 EFI 映像，它显然也不会以 UEFI 形式启动，因此缺少核心。