openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

x86, mtrr: Fix a type overflow in range_to_mtrr func 

When boot on sun G5+ with 4T mem, see an overflow in mtrr cleanup as below.

*BAD*gran_size: 2G      chunk_size: 2G  num_reg: 10     lose cover RAM:
-18014398505283592M

This is because 1<<31 sign extended. Use an unsigned long constant to
fix it.  Useful for mem larger than or equal to 4T.

-v2: Use 64bit constant instead of explicit type conversion as suggested
by Yinghai. Description updated too.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Link: http://lkml.kernel.org/r/4FC5A77F.6060505@oracle.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
zhenzhong.duan 2012-05-30 12:52:15 +08:00 committed by H. Peter Anvin
parent bbd771474e
commit 2da06af810
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/kernel/cpu/mtrr/cleanup.c
View File

@ -266,7 +266,7 @@ range_to_mtrr(unsigned int reg, unsigned long range_startk,
if (align > max_align)
align = max_align;
sizek = 1 << align;
sizek = 1UL << align;
if (debug_print) {
char start_factor = 'K', size_factor = 'K';
unsigned long start_base, size_base;