Messages in this thread Patch in this message | | | Date | Tue, 24 Mar 2009 09:42:29 GMT | From | "Pallipadi, Venkatesh" <> | Subject | [tip:x86/pat] x86, PAT, PCI: Change vma prot in pci_mmap to reflect inherited prot |
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Commit-ID: 571d1692d564e7782e55738ee87099fa038a3778 Gitweb: http://git.kernel.org/tip/571d1692d564e7782e55738ee87099fa038a3778 Author: Pallipadi, Venkatesh <venkatesh.pallipadi@intel.com> AuthorDate: Mon, 23 Mar 2009 12:07:20 -0700 Committer: Ingo Molnar <mingo@elte.hu> CommitDate: Tue, 24 Mar 2009 10:41:38 +0100
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> LKML-Reference: <20090323190720.GA16831@linux-os.sc.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
--- arch/x86/pci/i386.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-)
diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c index 5ead808..f234a37 100644 --- a/arch/x86/pci/i386.c +++ b/arch/x86/pci/i386.c @@ -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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