When the linux kernel is compiled, warning, appears in the environment of ubuntu,x86, and then ubuntu cannot be started.

enter: make ARCH=x86 modules_install

on the command line
      INSTALL fs/ext3/ext3.ko
      INSTALL fs/jbd/jbd.ko
      INSTALL kernel/configs.ko
      INSTALL sound/core/oss/snd-pcm-oss.ko
      INSTALL sound/core/snd-page-alloc.ko
      INSTALL sound/core/snd-pcm.ko
      INSTALL sound/core/snd-timer.ko
      INSTALL sound/core/snd.ko
      INSTALL ubuntu/fsam7400/fsam7400.ko
      DEPMOD  3.2.79
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol pci_enable_device
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol pci_enable_msi_block
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol __pci_register_driver
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol pci_disable_msi
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol _raw_spin_lock_irqsave
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol _raw_spin_lock
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol kmem_cache_alloc_trace
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol pci_unregister_driver
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol __stack_chk_fail
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol _raw_spin_unlock_bh
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol kmap
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol dma_alloc_from_coherent
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol dma_release_from_coherent
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol mcount
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol copy_to_user
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol kunmap
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol _raw_spin_unlock_irqrestore
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol pci_enable_msix
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol pci_set_master
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol _raw_spin_lock_bh
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol pci_disable_msix
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol pci_disable_device
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol pv_lock_ops
    WARNING: /lib/modules/3.2.79/misc/vmci.ko needs unknown symbol kmalloc_caches
    WARNING: /lib/modules/3.2.79/misc/vmhgfs.ko needs unknown symbol _raw_spin_lock
    WARNING: /lib/modules/3.2.79/misc/vmhgfs.ko needs unknown symbol kmem_cache_alloc_trace
    WARNING: /lib/modules/3.2.79/misc/vmhgfs.ko needs unknown symbol _raw_spin_unlock_bh
    WARNING: /lib/modules/3.2.79/misc/vmhgfs.ko needs unknown symbol kmap
    WARNING: /lib/modules/3.2.79/misc/vmhgfs.ko needs unknown symbol __kunmap_atomic
    WARNING: /lib/modules/3.2.79/misc/vmhgfs.ko needs unknown symbol mcount
    WARNING: /lib/modules/3.2.79/misc/vmhgfs.ko needs unknown symbol kunmap
    WARNING: /lib/modules/3.2.79/misc/vmhgfs.ko needs unknown symbol _raw_spin_lock_bh
    WARNING: /lib/modules/3.2.79/misc/vmhgfs.ko needs unknown symbol pv_lock_ops
    WARNING: /lib/modules/3.2.79/misc/vmhgfs.ko needs unknown symbol kmalloc_caches
    WARNING: /lib/modules/3.2.79/misc/vmhgfs.ko needs unknown symbol __kmap_atomic
    WARNING: /lib/modules/3.2.79/misc/vsock.ko needs unknown symbol security_sock_graft
    WARNING: /lib/modules/3.2.79/misc/vsock.ko needs unknown symbol _raw_write_lock_bh
    WARNING: /lib/modules/3.2.79/misc/vsock.ko needs unknown symbol _raw_write_unlock_bh
    WARNING: /lib/modules/3.2.79/misc/vsock.ko needs unknown symbol _raw_spin_lock
    WARNING: /lib/modules/3.2.79/misc/vsock.ko needs unknown symbol kmem_cache_alloc_trace
    WARNING: /lib/modules/3.2.79/misc/vsock.ko needs unknown symbol __stack_chk_fail
    WARNING: /lib/modules/3.2.79/misc/vsock.ko needs unknown symbol _raw_spin_unlock_bh
    WARNING: /lib/modules/3.2.79/misc/vsock.ko needs unknown symbol mcount
    WARNING: /lib/modules/3.2.79/misc/vsock.ko needs unknown symbol copy_to_user
    WARNING: /lib/modules/3.2.79/misc/vsock.ko needs unknown symbol _raw_spin_lock_bh
    WARNING: /lib/modules/3.2.79/misc/vsock.ko needs unknown symbol pv_lock_ops
    WARNING: /lib/modules/3.2.79/misc/vsock.ko needs unknown symbol kmalloc_caches
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol pci_enable_device
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol pci_choose_state
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol __pci_register_driver
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol pci_set_power_state
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol _raw_spin_lock_irqsave
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol _raw_spin_lock
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol pci_unregister_driver
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol dma_alloc_from_coherent
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol dma_release_from_coherent
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol mcount
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol _raw_spin_unlock_irqrestore
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol del_timer_sync
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol pci_set_master
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol pci_disable_device
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol page_address
    WARNING: /lib/modules/3.2.79/misc/vmxnet.ko needs unknown symbol pv_lock_ops
    

then execute make install, to complete the installation of the kernel. After rebooting, the startup fails and pops out:

    Gave up waiting for root device. Common problems: 
-boot args (cat.proc/cmdline) 
-check root delay=(did the system wait long enough?) 
-check root=(did teh system wait for the right device?) 
-miss modules (cat/proc/modules;ls/dev) 
ALERT! /dev/disk/by-uuid/acc3414d-926c-453c-b458-cf47088d77d2 does not exist.dropping to a shell! 
busybox v1.10.2(ubuntu 1:1.10.2-lubuntu6)bulit-in shell (ash). 

enter "help" for a list of built-in commands

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