errors when compiling 2.6 kernel source

["vinai" <vroopcha@mcw.edu>]

Hey Folks,

I tried compiling a 2.6 kernel from sources (2.6.11 from kernel.org to
be exact), and I got the following:

  LD      init/built-in.o
  LD      .tmp_vmlinux1
drivers/built-in.o(.text+0x4dbb8): In function `do_fd_request':
: undefined reference to `sti'
drivers/built-in.o(.text+0x4dd50): In function `set_timeout':
: undefined reference to `save_flags'
drivers/built-in.o(.text+0x4dd58): In function `set_timeout':
: undefined reference to `cli'
drivers/built-in.o(.text+0x4dd98): In function `set_timeout':
: undefined reference to `restore_flags'
drivers/built-in.o(.text+0x4eb2c): In function `grab_drive':
: undefined reference to `save_flags'
drivers/built-in.o(.text+0x4eb30): In function `grab_drive':
: undefined reference to `cli'
drivers/built-in.o(.text+0x4eb94): In function `grab_drive':
: undefined reference to `restore_flags'
drivers/built-in.o(.text+0x4ebc8): In function `grab_drive':
: undefined reference to `restore_flags'
drivers/built-in.o(.text+0x4ebec): In function `release_drive':
: undefined reference to `save_flags'
drivers/built-in.o(.text+0x4ebf0): In function `release_drive':
: undefined reference to `cli'
drivers/built-in.o(.text+0x4ec08): In function `release_drive':
: undefined reference to `restore_flags'
make: *** [.tmp_vmlinux1] Error 1

What's causing this ?

cheers
vinai