x86: Fix 'reservetop=' functionality

When specifying the 'reservetop=0xbadc0de' kernel parameter,
the kernel will stop booting due to a early_ioremap bug that
relates to commit 8827247ff.

The root cause of boot failure problem is the value of
'slot_virt[i]' was initialized in setup_arch->early_ioremap_init().
But later in setup_arch, the function 'parse_early_param' will
modify 'FIXADDR_TOP' when 'reservetop=0xbadc0de' being specified.

The simplest fix might be use __fix_to_virt(idx0) to get updated
value of 'FIXADDR_TOP' in '__early_ioremap' instead of reference
old value from slot_virt[slot] directly.

Changelog since v0:

-v1: When reservetop being handled then FIXADDR_TOP get
     adjusted, Hence check prev_map then re-initialize slot_virt and
     PMD based on new FIXADDR_TOP.

-v2: place fixup_early_ioremap hence call early_ioremap_init in
     reserve_top_address  to re-initialize slot_virt and
     corresponding PMD when parse_reservertop

-v3: move fixup_early_ioremap out of reserve_top_address to make
     sure other clients of reserve_top_address like xen/lguest won't
     broken

Signed-off-by: Liang Li <[email protected]>
Tested-by: Konrad Rzeszutek Wilk <[email protected]>
Acked-by: Yinghai Lu <[email protected]>
Acked-by: Jeremy Fitzhardinge <[email protected]>
Cc: Wang Chen <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Andrew Morton <[email protected]>
LKML-Reference: <[email protected]>
[ fixed three small cleanliness details in fixup_early_ioremap() ]
Signed-off-by: Ingo Molnar <[email protected]>

0 files changed, 0 insertions, 0 deletions