[PATCH v10 07/27] powerpc: cleanup AMR, IAMR when a key is allocated or freed
From: Ram Pai <hidden>
Date: 2018-01-19 01:52:22
Also in:
linux-arch, linux-kselftest, linux-mm, lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
Cleanup the bits corresponding to a key in the AMR, and IAMR register, when the key is newly allocated/activated or is freed. We dont want some residual bits cause the hardware enforce unintended behavior when the key is activated or freed. Reviewed-by: Thiago Jung Bauermann <redacted> Signed-off-by: Ram Pai <redacted> --- arch/powerpc/include/asm/pkeys.h | 12 ++++++++++++ 1 files changed, 12 insertions(+), 0 deletions(-)
diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index 1e8cef2..9964b46 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h@@ -69,6 +69,8 @@ static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey) __mm_pkey_is_allocated(mm, pkey)); } +extern void __arch_activate_pkey(int pkey); +extern void __arch_deactivate_pkey(int pkey); /* * Returns a positive, 5-bit key on success, or -1 on failure. * Relies on the mmap_sem to protect against concurrency in mm_pkey_alloc() and
@@ -96,6 +98,12 @@ static inline int mm_pkey_alloc(struct mm_struct *mm) ret = ffz((u32)mm_pkey_allocation_map(mm)); __mm_pkey_allocated(mm, ret); + + /* + * Enable the key in the hardware + */ + if (ret > 0) + __arch_activate_pkey(ret); return ret; }
@@ -107,6 +115,10 @@ static inline int mm_pkey_free(struct mm_struct *mm, int pkey) if (!mm_pkey_is_allocated(mm, pkey)) return -EINVAL; + /* + * Disable the key in the hardware + */ + __arch_deactivate_pkey(pkey); __mm_pkey_free(mm, pkey); return 0;
--
1.7.1