From 6eee1bbad1c39396bcfc2add3fd5bde5b1e7c561 Mon Sep 17 00:00:00 2001 From: Venkatesh Pallipadi Date: Mon, 30 Mar 2009 18:50:19 +0000 Subject: [PATCH] x86, PAT, PCI: Change vma prot in pci_mmap to reflect inherited prot 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 Signed-off-by: Venkatesh Pallipadi Signed-off-by: Suresh Siddha Cc: Jesse Barnes Cc: Dave Airlie LKML-Reference: <20090323190720.GA16831@linux-os.sc.intel.com> Signed-off-by: Ingo Molnar Signed-off-by: Chris Wright Signed-off-by: Greg Kroah-Hartman --- arch/x86/pci/i386.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c index 844df0cbbd3e..d88c1b3b2301 100644 --- a/arch/x86/pci/i386.c +++ b/arch/x86/pci/i386.c @@ -329,6 +329,9 @@ 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) || -- 2.39.2