diff options
| author |   Li Yang <leoli@freescale.com> | 2010-05-07 16:38:34 +0800 |
|---|---|---|
| committer |   Kumar Gala <galak@kernel.crashing.org> | 2010-05-17 10:56:16 -0500 |
| commit | 78e2e68a2b79f394b7cd61e07987a8a89af907f7 (patch) | |
| tree | 41b534f2e557503a1d78f01d852e5eb8cb61b95a /arch/powerpc/kernel | |
| parent | powerpc/8610: add probing for individual DMA channels, not just DMA controllers (diff) | |
| download | linux-dev-78e2e68a2b79f394b7cd61e07987a8a89af907f7.tar.xz linux-dev-78e2e68a2b79f394b7cd61e07987a8a89af907f7.zip | |
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>
Diffstat (limited to 'arch/powerpc/kernel')
| -rw-r--r-- | arch/powerpc/kernel/head_fsl_booke.S | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S index 725526547994..edd4a57fd29e 100644 --- a/arch/powerpc/kernel/head_fsl_booke.S +++ b/arch/powerpc/kernel/head_fsl_booke.S @@ -639,6 +639,13 @@ interrupt_base: rlwinm r12,r12,0,16,1 mtspr SPRN_MAS1,r12 + /* Make up the required permissions for kernel code */ +#ifdef CONFIG_PTE_64BIT + li r13,_PAGE_PRESENT | _PAGE_BAP_SX + oris r13,r13,_PAGE_ACCESSED@h +#else + li r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC +#endif b 4f /* Get the PGD for the current thread */ @@ -646,15 +653,15 @@ interrupt_base: mfspr r11,SPRN_SPRG_THREAD lwz r11,PGDIR(r11) -4: - /* Make up the required permissions */ + /* Make up the required permissions for user code */ #ifdef CONFIG_PTE_64BIT - li r13,_PAGE_PRESENT | _PAGE_EXEC + li r13,_PAGE_PRESENT | _PAGE_BAP_UX oris r13,r13,_PAGE_ACCESSED@h #else li r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC #endif +4: FIND_PTE andc. r13,r13,r11 /* Check permission */ |