x86: PAT bug fix for attribute type check after reserve_memtype
Bug fixes for reserve_memtype() call in __ioremap and pci_mmap_page_range().
If reserve_memtype returns non-zero, then it is an error and subsequent free is
not required. Requested and returned prot value check should be done when
reserve_memtype returns success.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index 4ebf52f..2ead723 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -328,6 +328,7 @@
unsigned long len = vma->vm_end - vma->vm_start;
unsigned long flags;
unsigned long new_flags;
+ int retval;
/* I/O space cannot be accessed via normal processor loads and
* stores on this platform.
@@ -344,7 +345,11 @@
vma->vm_page_prot = __pgprot(prot);
flags = pgprot_val(vma->vm_page_prot) & _PAGE_CACHE_MASK;
- if (reserve_memtype(addr, addr + len, flags, &new_flags)) {
+ retval = reserve_memtype(addr, addr + len, flags, &new_flags);
+ if (retval)
+ return retval;
+
+ if (flags != new_flags) {
/*
* Do not fallback to certain memory types with certain
* requested type: