powerpc/fsl-booke: Fix InstructionTLBError execute permission check
authorLi Yang <leoli@freescale.com>
Fri, 7 May 2010 08:38:34 +0000 (16:38 +0800)
committerKumar Gala <galak@kernel.crashing.org>
Thu, 13 May 2010 19:00:49 +0000 (14:00 -0500)
commitfa6bd996db2fbecd7a9a408c158105c55a51fe41
treef6706c6d0cd4cb71353f8591218020255da3dd68
parent131c6c9eddfa252e376edb4aeff9c7fe1b96a798
powerpc/fsl-booke: Fix InstructionTLBError execute permission check

In CONFIG_PTE_64BIT the PTE format has unique permission bits for user
and supervisor execute.  However on !CONFIG_PTE_64BIT we overload the
supervisor bit to imply user execute with _PAGE_USER set.  This allows
us to use the same permission check mask for user or supervisor code on
!CONFIG_PTE_64BIT.

However, on CONFIG_PTE_64BIT we map _PAGE_EXEC to _PAGE_BAP_UX so we
need a different permission mask based on the fault coming from a kernel
address or user space.

Without unique permission masks we see issues like the following with
modules:

Unable to handle kernel paging request for instruction fetch
Faulting instruction address: 0xf938d040
Oops: Kernel access of bad area, sig: 11 [#1]

Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Jin Qing <b24347@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
arch/powerpc/kernel/head_fsl_booke.S