On 08/09/2017 01:07 PM, Tycho Andersen wrote: > From: Juerg Haefliger <juerg.haefli...@hpe.com> > > XPFO (eXclusive Page Frame Ownership) doesn't support section mappings > yet, so disable it if XPFO is turned on. > > Signed-off-by: Juerg Haefliger <juerg.haefli...@canonical.com> > Tested-by: Tycho Andersen <ty...@docker.com> > --- > arch/arm64/mm/mmu.c | 14 +++++++++++++- > 1 file changed, 13 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c > index f1eb15e0e864..38026b3ccb46 100644 > --- a/arch/arm64/mm/mmu.c > +++ b/arch/arm64/mm/mmu.c > @@ -176,6 +176,18 @@ static void alloc_init_cont_pte(pmd_t *pmd, unsigned > long addr, > } while (addr = next, addr != end); > } > > +static inline bool use_section_mapping(unsigned long addr, unsigned long > next, > + unsigned long phys) > +{ > + if (IS_ENABLED(CONFIG_XPFO)) > + return false; > + > + if (((addr | next | phys) & ~SECTION_MASK) != 0) > + return false; > + > + return true; > +} > + > static void init_pmd(pud_t *pud, unsigned long addr, unsigned long end, > phys_addr_t phys, pgprot_t prot, > phys_addr_t (*pgtable_alloc)(void), int flags) > @@ -190,7 +202,7 @@ static void init_pmd(pud_t *pud, unsigned long addr, > unsigned long end, > next = pmd_addr_end(addr, end); > > /* try section mapping first */ > - if (((addr | next | phys) & ~SECTION_MASK) == 0 && > + if (use_section_mapping(addr, next, phys) && > (flags & NO_BLOCK_MAPPINGS) == 0) { > pmd_set_huge(pmd, phys, prot); > >
There is already similar logic to disable section mappings for debug_pagealloc at the start of map_mem, can you take advantage of that? Thanks, Laura