• Rusty Russell's avatar
    lguest: populate initial_page_table · da32dac1
    Rusty Russell authored
    Two x86 patches broke lguest:
    1) v2.6.35-492-g72d7c3b3, which changed x86 to use the memblock allocator.
    
    In lguest, the host places linear page tables at the top of mem, which
    used to be enough to get us up to the swapper_pg_dir page tables.  With
    the first patch, the direct mapping tables used that memory:
    
    Before: kernel direct mapping tables up to 4000000 @ 7000-1a000
    After: kernel direct mapping tables up to 4000000 @ 3fed000-4000000
    
    I initially fixed this by lying about the amount of memory we had, so
    the kernel wouldn't blatt the lguest boot pagetables (yuk!), but then...
    
    2) v2.6.36-rc8-54-gb40827fa
    
    , which made x86 boot use initial_page_table.
    
    This was initialized in a part of head_32.S which isn't executed by
    lguest; it is then copied into swapper_pg_dir.  So we have to initialize
    it; and anyway we switch to it before we blatt the old tables, so that
    fixes the previous damage as well.
    
    For the moment, I cut & pasted the code into lguest's boot code, but
    next merge window I will merge them.
    Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
    Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
    Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
    To: x86@kernel.org
    da32dac1
boot.c 47.4 KB