powerpc: Fix ioremap_flags() with book3e pte definition

We can't just clear the user read permission in book3e pte, because
that will also clear supervisor read permission.  This surely isn't
desired.  Fix the problem by adding the supervisor read back.

BenH: Slightly simplified the ifdef and applied to ppc64 too

Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Benjamin Herrenschmidt 2010-04-07 14:39:36 +10:00
parent f467bc148d
commit 55052eeca6
2 changed files with 16 additions and 0 deletions

View file

@ -146,6 +146,14 @@ ioremap_flags(phys_addr_t addr, unsigned long size, unsigned long flags)
/* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
flags &= ~(_PAGE_USER | _PAGE_EXEC);
#ifdef _PAGE_BAP_SR
/* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format
* which means that we just cleared supervisor access... oops ;-) This
* restores it
*/
flags |= _PAGE_BAP_SR;
#endif
return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
}
EXPORT_SYMBOL(ioremap_flags);

View file

@ -265,6 +265,14 @@ void __iomem * ioremap_flags(phys_addr_t addr, unsigned long size,
/* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
flags &= ~(_PAGE_USER | _PAGE_EXEC);
#ifdef _PAGE_BAP_SR
/* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format
* which means that we just cleared supervisor access... oops ;-) This
* restores it
*/
flags |= _PAGE_BAP_SR;
#endif
if (ppc_md.ioremap)
return ppc_md.ioremap(addr, size, flags, caller);
return __ioremap_caller(addr, size, flags, caller);