xen/i386: follow-up to "replace order-based range checking of M2P table by linear one"

The numbers obtained from the hypervisor really can't ever lead to an
overflow here, only the original calculation going through the order
of the range could have. This avoids the (as Jeremy points outs)
somewhat ugly NULL-based calculation here.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Jan Beulich 2011-09-15 08:52:40 +01:00 committed by Konrad Rzeszutek Wilk
parent 7736594836
commit 61cca2fab7
1 changed files with 2 additions and 4 deletions

View File

@ -1721,10 +1721,8 @@ void __init xen_setup_machphys_mapping(void)
machine_to_phys_nr = MACH2PHYS_NR_ENTRIES;
}
#ifdef CONFIG_X86_32
if ((machine_to_phys_mapping + machine_to_phys_nr)
< machine_to_phys_mapping)
machine_to_phys_nr = (unsigned long *)NULL
- machine_to_phys_mapping;
WARN_ON((machine_to_phys_mapping + (machine_to_phys_nr - 1))
< machine_to_phys_mapping);
#endif
}