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Subject[PATCH 1/2] UIO: add pgprot_noncached() to UIO mmap code
Date
From: Jean-Samuel Chenard <jsamch@gmail.com>

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>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/uio/uio.c | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c
index e8a01f2..1175908 100644
--- a/drivers/uio/uio.c
+++ b/drivers/uio/uio.c
@@ -470,6 +470,8 @@ static int uio_mmap_physical(struct vm_area_struct *vma)

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,
--
1.5.4.3


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