x86: mtrr: Fix high_width computation when phys-addr is >= 44bit
found one system where cpu address line is 44bits, mtrr printout
is not right:
[ 0.000000] MTRR variable ranges enabled:
[ 0.000000] 0 base 0 00000000 mask FF0 00000000 write-back
[ 0.000000] 1 base 10 00000000 mask FFF 80000000 write-back
[ 0.000000] 2 base 0 80000000 mask FFF 80000000 uncachable
[ 0.000000] 3 base 0 7F800000 mask FFF FF800000 uncachable
Li Zefan and Frederic pointed out the high_width could be -4 some how.
It turns out when phys_addr is 44bit, size_or_mask will be
ffffffff,00000000 so ffs(size_or_mask) will be 0.
Try to check low 32 bit, to get correct high_width.
Signed-off-by: Yinghai Lu <yinghai@kerne.org>
Also-analyzed-by: Frederic Weisbecker <fweisbec@gmail.com>
Also-analyzed-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Zhaolei <zhaolei@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A026540.8060504@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
1 file changed