[PATCH v10 26/27] mm, x86 : introduce arch_pkeys_enabled()
From: Ram Pai <hidden>
Date: 2018-01-19 01:54:34
Also in:
linux-arch, linux-kselftest, linux-mm, lkml
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
Arch neutral code needs to know if the architecture supports protection keys to display protection key in smaps. Hence introducing arch_pkeys_enabled(). This patch also provides x86 implementation for arch_pkeys_enabled(). Signed-off-by: Ram Pai <redacted> --- arch/x86/include/asm/pkeys.h | 1 + arch/x86/kernel/fpu/xstate.c | 5 +++++ include/linux/pkeys.h | 5 +++++ 3 files changed, 11 insertions(+), 0 deletions(-)
diff --git a/arch/x86/include/asm/pkeys.h b/arch/x86/include/asm/pkeys.h
index a0ba1ff..f6c287b 100644
--- a/arch/x86/include/asm/pkeys.h
+++ b/arch/x86/include/asm/pkeys.h@@ -6,6 +6,7 @@ extern int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, unsigned long init_val); +extern bool arch_pkeys_enabled(void); /* * Try to dedicate one of the protection keys to be used as an
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index 87a57b7..4f566e9 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c@@ -945,6 +945,11 @@ int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, return 0; } + +bool arch_pkeys_enabled(void) +{ + return boot_cpu_has(X86_FEATURE_OSPKE); +} #endif /* ! CONFIG_ARCH_HAS_PKEYS */ /*
diff --git a/include/linux/pkeys.h b/include/linux/pkeys.h
index 0794ca7..3ca2e44 100644
--- a/include/linux/pkeys.h
+++ b/include/linux/pkeys.h@@ -35,6 +35,11 @@ static inline int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, return 0; } +static inline bool arch_pkeys_enabled(void) +{ + return false; +} + static inline void copy_init_pkru_to_fpregs(void) { }
--
1.7.1