Messages in this thread Patch in this message |  | | | Date | Wed, 29 Apr 2009 15:07:08 -0700 | | From | Greg KH <> | | Subject | [patch 09/58] x86, PAT, PCI: Change vma prot in pci_mmap to reflect inherited prot |
| |
2.6.27-stable review patch. If anyone has any objections, please let us know.
------------------ From: Pallipadi, Venkatesh <venkatesh.pallipadi@intel.com>
upstream commit: 9cdec049389ce2c324fd1ec508a71528a27d4a07
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> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> --- arch/x86/pci/i386.c | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/x86/pci/i386.c +++ b/arch/x86/pci/i386.c @@ -326,6 +326,9 @@ int pci_mmap_page_range(struct pci_dev * 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) ||
|  |