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/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 6cd3418..3f7f05e 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -124,6 +124,7 @@
struct vm_struct *area;
unsigned long new_prot_val;
pgprot_t prot;
+ int retval;
/* Don't allow wraparound or zero size */
last_addr = phys_addr + size - 1;
@@ -163,8 +164,14 @@
phys_addr &= PAGE_MASK;
size = PAGE_ALIGN(last_addr+1) - phys_addr;
- if (reserve_memtype(phys_addr, phys_addr + size,
- prot_val, &new_prot_val)) {
+ retval = reserve_memtype(phys_addr, phys_addr + size,
+ prot_val, &new_prot_val);
+ if (retval) {
+ printk("reserve_memtype returned %d\n", retval);
+ return NULL;
+ }
+
+ if (prot_val != new_prot_val) {
/*
* Do not fallback to certain memory types with certain
* requested type: