Commit dee7cbb2 authored by Venki Pallipadi's avatar Venki Pallipadi Committed by Ingo Molnar
Browse files

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: default avatarVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>

Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 9307caca

arch/x86/mm/ioremap.c

+9 −2
Original line number Diff line number Diff line
@@ -124,6 +124,7 @@ static void __iomem *__ioremap(resource_size_t phys_addr, unsigned long size, 
	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 @@ static void __iomem *__ioremap(resource_size_t phys_addr, unsigned long size, 
	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:

arch/x86/pci/i386.c

+6 −1
Original line number Diff line number Diff line
@@ -328,6 +328,7 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma, 
	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 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma, 
	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:

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