diff options
| -rw-r--r-- | arch/x86/mm/pat.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index 738fd0f24958..eb1bf000d12e 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -481,12 +481,16 @@ static inline int range_is_allowed(unsigned long pfn, unsigned long size) return 1; } #else +/* This check is needed to avoid cache aliasing when PAT is enabled */ static inline int range_is_allowed(unsigned long pfn, unsigned long size) { u64 from = ((u64)pfn) << PAGE_SHIFT; u64 to = from + size; u64 cursor = from; + if (!pat_enabled) + return 1; + while (cursor < to) { if (!devmem_is_allowed(pfn)) { printk(KERN_INFO |