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>
This commit is contained in:
Pallipadi, Venkatesh 2009-03-23 12:07:20 -07:00 committed by Ingo Molnar
parent 7f00a2495b
commit 9cdec04938
1 changed files with 3 additions and 0 deletions

View File

@ -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) ||