Commit 9cdec049 authored Mar 23, 2009 by Pallipadi, Venkatesh Committed by Ingo Molnar Mar 24, 2009

x86, PAT, PCI: Change vma prot in pci_mmap to reflect inherited prot

While looking at the issue in the thread:

  http://marc.info/?l=dri-devel&m=123606627824556&w=2



noticed a bug in pci PAT code and memory type setting.

PCI mmap code did not set the proper protection in vma, when it
inherited protection in reserve_memtype. This bug only affects
the case where there exists a WC mapping before X does an mmap
with /proc or /sys pci interface. This will cause X userlevel
mmap from /proc or /sysfs to fail on fork.

Reported-by: Kevin Winchester <kjwinchester@gmail.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Dave Airlie <airlied@redhat.com>
Cc: <stable@kernel.org>
LKML-Reference: <20090323190720.GA16831@linux-os.sc.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

parent 7f00a249

arch/x86/pci/i386.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -319,6 +319,9 @@ int pci_mmap_page_range(struct pci_dev dev, struct vm_area_struct vma,
		return -EINVAL;
		}
		flags = new_flags;
		vma->vm_page_prot = __pgprot(
		(pgprot_val(vma->vm_page_prot) & ~_PAGE_CACHE_MASK) \|
		flags);
		}

		if (((vma->vm_pgoff < max_low_pfn_mapped) \|\|

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