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Subject[PATCH] Add pgprot_noncached() to UIO mmap code
From: Jean-Samuel Chenard <jsamch@gmail.com>
To: Greg KH <greg@kroah.com>
Cc: Hans J Koch <hjk@linutronix.de>, linux-kernel@vger.kernel.org,
Juergen Beisert <juergen127@kreuzholzen.de>
Date: Fri, 14 Mar 2008 11:19:49 +0100
Subject: Add pgprot_noncached() to UIO mmap code

Mapping of physical memory in UIO needs pgprot_noncached() to ensure
that IO memory is not cached. Without pgprot_noncached(), it (accidentally)
works on x86 and arm, but fails on PPC.

Signed-off-by: Jean-Samuel Chenard <jsamch@gmail.com>
Signed-off-by: Hans J Koch <hjk@linutronix.de>

---
drivers/uio/uio.c | 2 ++
1 file changed, 2 insertions(+)

Index: linux-2.6.25-rc/drivers/uio/uio.c
===================================================================
--- linux-2.6.25-rc.orig/drivers/uio/uio.c 2008-03-14 11:00:59.000000000 +0100
+++ linux-2.6.25-rc/drivers/uio/uio.c 2008-03-14 11:03:13.000000000 +0100
@@ -470,6 +470,8 @@

vma->vm_flags |= VM_IO | VM_RESERVED;

+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
return remap_pfn_range(vma,
vma->vm_start,
idev->info->mem[mi].addr >> PAGE_SHIFT,

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