[PATCH AUTOSEL for 4.4 135/167] MIPS: mm: fixed mappings: correct initialisation

Sasha Levin
2018-03-19T16:10:52Z

From: Marcin Nowakowski <marcin.nowakowski@imgtec.com>

[ Upstream commit 71eb989ab5a110df8bcbb9609bacde73feacbedd ]

fixrange_init operates at PMD-granularity and expects the addresses to
be PMD-size aligned, but currently that might not be the case for
PKMAP_BASE unless it is defined properly, so ensure a correct alignment
is used before passing the address to fixrange_init.

fixed mappings: only align the start address that is passed to
fixrange_init rather than the value before adding the size, as we may
end up with uninitialised upper part of the range.

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15948/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
arch/mips/mm/pgtable-32.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/mips/mm/pgtable-32.c b/arch/mips/mm/pgtable-32.c
index adc6911ba748..b19a3c506b1e 100644
--- a/arch/mips/mm/pgtable-32.c
+++ b/arch/mips/mm/pgtable-32.c
@@ -51,15 +51,15 @@ void __init pagetable_init(void)
/*
* Fixed mappings:
*/
- vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
- fixrange_init(vaddr, vaddr + FIXADDR_SIZE, pgd_base);
+ vaddr = __fix_to_virt(__end_of_fixed_addresses - 1);
+ fixrange_init(vaddr & PMD_MASK, vaddr + FIXADDR_SIZE, pgd_base);

#ifdef CONFIG_HIGHMEM
/*
* Permanent kmaps:
*/
vaddr = PKMAP_BASE;
- fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base);
+ fixrange_init(vaddr & PMD_MASK, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base);

pgd = swapper_pg_dir + __pgd_offset(vaddr);
pud = pud_offset(pgd, vaddr);
--
2.14.1