Only 4bits are allocated in the vma flags to hold 16 keys. This is
sufficient on x86. PowerPC supports 32 keys, which needs 5bits.
Allocate an additional bit.
cc: Dave Hansen <dave.han...@intel.com>
cc: Michael Ellermen <m...@ellerman.id.au>
cc: Benjamin Herrenschmidt <b...@kernel.crashing.org>
cc: Andrew Morton <a...@linux-foundation.org>
Reviewed-by: Ingo Molnar <mi...@kernel.org>
Acked-by: Balbir Singh <bsinghar...@gmail.com>
Signed-off-by: Ram Pai <linux...@us.ibm.com>
---
fs/proc/task_mmu.c | 1 +
include/linux/mm.h | 8 +++++++-
2 files changed, 8 insertions(+), 1 deletions(-)
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 0c9e392..3ddddc7 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -679,6 +679,7 @@ static void show_smap_vma_flags(struct seq_file *m, struct
vm_area_struct *vma)
[ilog2(VM_PKEY_BIT1)] = "",
[ilog2(VM_PKEY_BIT2)] = "",
[ilog2(VM_PKEY_BIT3)] = "",
+ [ilog2(VM_PKEY_BIT4)] = "",
#endif /* CONFIG_ARCH_HAS_PKEYS */
};
size_t i;
diff --git a/include/linux/mm.h b/include/linux/mm.h
index c6a6f24..cca67d1 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -230,10 +230,16 @@ extern int overcommit_kbytes_handler(struct ctl_table *,
int, void __user *,
#ifdef CONFIG_ARCH_HAS_PKEYS
# define VM_PKEY_SHIFT VM_HIGH_ARCH_BIT_0
-# define VM_PKEY_BIT0 VM_HIGH_ARCH_0 /* A protection key is a 4-bit value */
+/* Protection key is a 4-bit value on x86 and 5-bit value on ppc64 */
+# define VM_PKEY_BIT0 VM_HIGH_ARCH_0
# define VM_PKEY_BIT1 VM_HIGH_ARCH_1
# define VM_PKEY_BIT2 VM_HIGH_ARCH_2
# define VM_PKEY_BIT3 VM_HIGH_ARCH_3
+#if defined(CONFIG_PPC)
+# define VM_PKEY_BIT4 VM_HIGH_ARCH_4
+#else
+# define VM_PKEY_BIT4 0
+#endif
#endif /* CONFIG_ARCH_HAS_PKEYS */
#if defined(CONFIG_X86)
--
1.7.1
