On Tue, 2017-06-27 at 03:11 -0700, Ram Pai wrote: > Currently there are only 4bits in the vma flags to support 16 keys > on x86. powerpc supports 32 keys, which needs 5bits. This patch > introduces an addition bit in the vma flags. > > Signed-off-by: Ram Pai <linux...@us.ibm.com> > --- > fs/proc/task_mmu.c | 6 +++++- > include/linux/mm.h | 18 +++++++++++++----- > 2 files changed, 18 insertions(+), 6 deletions(-) > > diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c > index f0c8b33..2ddc298 100644 > --- a/fs/proc/task_mmu.c > +++ b/fs/proc/task_mmu.c > @@ -666,12 +666,16 @@ static void show_smap_vma_flags(struct seq_file *m, > struct vm_area_struct *vma) > [ilog2(VM_MERGEABLE)] = "mg", > [ilog2(VM_UFFD_MISSING)]= "um", > [ilog2(VM_UFFD_WP)] = "uw", > -#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS > +#ifdef CONFIG_ARCH_HAS_PKEYS > /* These come out via ProtectionKey: */ > [ilog2(VM_PKEY_BIT0)] = "", > [ilog2(VM_PKEY_BIT1)] = "", > [ilog2(VM_PKEY_BIT2)] = "", > [ilog2(VM_PKEY_BIT3)] = "", > +#endif /* CONFIG_ARCH_HAS_PKEYS */ > +#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS > + /* Additional bit in ProtectionKey: */ > + [ilog2(VM_PKEY_BIT4)] = "", > #endif
Not sure why these are linked with smap bits, but I guess the keys live in the Supervisor Mode Access Prevention area? Balbir Singh.
