x86, mm: is_untracked_pat_range() takes a normal semiclosed range
is_untracked_pat_range() -- like its components, is_ISA_range() and
is_GRU_range(), takes a normal semiclosed interval (>=, <) whereas the
PAT code called it as if it took a closed range (>=, <=). Fix.
Although this is a bug, I believe it is non-manifest, simply because
none of the callers will call this with non-page-aligned addresses.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20091119202341.GA4420@sgi.com>
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 1de2094..a34c785 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -274,7 +274,7 @@
/*
* PAT type is always WB for untracked ranges, so no need to check.
*/
- if (x86_platform.is_untracked_pat_range(paddr, paddr + size - 1))
+ if (x86_platform.is_untracked_pat_range(paddr, paddr + size))
return 1;
/*
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 38a66ef..b5bc08c 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -394,7 +394,7 @@
}
/* Low ISA region is always mapped WB in page table. No need to track */
- if (x86_platform.is_untracked_pat_range(start, end - 1)) {
+ if (x86_platform.is_untracked_pat_range(start, end)) {
if (new_type)
*new_type = _PAGE_CACHE_WB;
return 0;
@@ -505,7 +505,7 @@
return 0;
/* Low ISA region is always mapped WB. No need to track */
- if (x86_platform.is_untracked_pat_range(start, end - 1))
+ if (x86_platform.is_untracked_pat_range(start, end))
return 0;
is_range_ram = pat_pagerange_is_ram(start, end);
@@ -588,7 +588,7 @@
int rettype = _PAGE_CACHE_WB;
struct memtype *entry;
- if (x86_platform.is_untracked_pat_range(paddr, paddr + PAGE_SIZE - 1))
+ if (x86_platform.is_untracked_pat_range(paddr, paddr + PAGE_SIZE))
return rettype;
if (pat_pagerange_is_ram(paddr, paddr + PAGE_SIZE)) {