From: Dave Hansen <dave@sr71.net>
To: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org, x86@kernel.org, Dave Hansen <dave@sr71.net>,
dave.hansen@linux.intel.com
Subject: [PATCH 04/31] x86, pkeys: cpuid bit definition
Date: Wed, 06 Jan 2016 16:01:10 -0800 [thread overview]
Message-ID: <20160107000110.21494EF8@viggo.jf.intel.com> (raw)
In-Reply-To: <20160107000104.1A105322@viggo.jf.intel.com>
From: Dave Hansen <dave.hansen@linux.intel.com>
There are two CPUID bits for protection keys. One is for whether
the CPU contains the feature, and the other will appear set once
the OS enables protection keys. Specifically:
Bit 04: OSPKE. If 1, OS has set CR4.PKE to enable
Protection keys (and the RDPKRU/WRPKRU instructions)
This is because userspace can not see CR4 contents, but it can
see CPUID contents.
X86_FEATURE_PKU is referred to as "PKU" in the hardware documentation:
CPUID.(EAX=07H,ECX=0H):ECX.PKU [bit 3]
X86_FEATURE_OSPKE is "OSPKU":
CPUID.(EAX=07H,ECX=0H):ECX.OSPKE [bit 4]
These are the first CPU features which need to look at the
ECX word in CPUID leaf 0x7, so this patch also includes
fetching that word in to the cpuinfo->x86_capability[] array.
Add it to the disabled-features mask when its config option is
off. Even though we are not using it here, we also extend the
REQUIRED_MASK_BIT_SET() macro to keep it mirroring the
DISABLED_MASK_BIT_SET() version.
This means that in almost all code, you should use:
cpu_has(c, X86_FEATURE_PKU)
and *not* the CONFIG option.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
---
b/arch/x86/include/asm/cpufeature.h | 56 ++++++++++++++++++-----------
b/arch/x86/include/asm/disabled-features.h | 13 ++++++
b/arch/x86/include/asm/required-features.h | 5 ++
b/arch/x86/kernel/cpu/common.c | 1
4 files changed, 54 insertions(+), 21 deletions(-)
diff -puN arch/x86/include/asm/cpufeature.h~pkeys-01-cpuid arch/x86/include/asm/cpufeature.h
--- a/arch/x86/include/asm/cpufeature.h~pkeys-01-cpuid 2016-01-06 15:50:04.310097377 -0800
+++ b/arch/x86/include/asm/cpufeature.h 2016-01-06 15:50:04.318097738 -0800
@@ -12,7 +12,7 @@
#include <asm/disabled-features.h>
#endif
-#define NCAPINTS 14 /* N 32-bit words worth of info */
+#define NCAPINTS 15 /* N 32-bit words worth of info */
#define NBUGINTS 1 /* N 32-bit bug flags */
/*
@@ -258,6 +258,10 @@
/* AMD-defined CPU features, CPUID level 0x80000008 (ebx), word 13 */
#define X86_FEATURE_CLZERO (13*32+0) /* CLZERO instruction */
+/* Intel-defined CPU features, CPUID level 0x00000007:0 (ecx), word 13 */
+#define X86_FEATURE_PKU (14*32+ 3) /* Protection Keys for Userspace */
+#define X86_FEATURE_OSPKE (14*32+ 4) /* OS Protection Keys Enable */
+
/*
* BUG word(s)
*/
@@ -298,28 +302,38 @@ extern const char * const x86_bug_flags[
test_bit(bit, (unsigned long *)((c)->x86_capability))
#define REQUIRED_MASK_BIT_SET(bit) \
- ( (((bit)>>5)==0 && (1UL<<((bit)&31) & REQUIRED_MASK0)) || \
- (((bit)>>5)==1 && (1UL<<((bit)&31) & REQUIRED_MASK1)) || \
- (((bit)>>5)==2 && (1UL<<((bit)&31) & REQUIRED_MASK2)) || \
- (((bit)>>5)==3 && (1UL<<((bit)&31) & REQUIRED_MASK3)) || \
- (((bit)>>5)==4 && (1UL<<((bit)&31) & REQUIRED_MASK4)) || \
- (((bit)>>5)==5 && (1UL<<((bit)&31) & REQUIRED_MASK5)) || \
- (((bit)>>5)==6 && (1UL<<((bit)&31) & REQUIRED_MASK6)) || \
- (((bit)>>5)==7 && (1UL<<((bit)&31) & REQUIRED_MASK7)) || \
- (((bit)>>5)==8 && (1UL<<((bit)&31) & REQUIRED_MASK8)) || \
- (((bit)>>5)==9 && (1UL<<((bit)&31) & REQUIRED_MASK9)) )
+ ( (((bit)>>5)==0 && (1UL<<((bit)&31) & REQUIRED_MASK0 )) || \
+ (((bit)>>5)==1 && (1UL<<((bit)&31) & REQUIRED_MASK1 )) || \
+ (((bit)>>5)==2 && (1UL<<((bit)&31) & REQUIRED_MASK2 )) || \
+ (((bit)>>5)==3 && (1UL<<((bit)&31) & REQUIRED_MASK3 )) || \
+ (((bit)>>5)==4 && (1UL<<((bit)&31) & REQUIRED_MASK4 )) || \
+ (((bit)>>5)==5 && (1UL<<((bit)&31) & REQUIRED_MASK5 )) || \
+ (((bit)>>5)==6 && (1UL<<((bit)&31) & REQUIRED_MASK6 )) || \
+ (((bit)>>5)==7 && (1UL<<((bit)&31) & REQUIRED_MASK7 )) || \
+ (((bit)>>5)==8 && (1UL<<((bit)&31) & REQUIRED_MASK8 )) || \
+ (((bit)>>5)==9 && (1UL<<((bit)&31) & REQUIRED_MASK9 )) || \
+ (((bit)>>5)==10 && (1UL<<((bit)&31) & REQUIRED_MASK10)) || \
+ (((bit)>>5)==11 && (1UL<<((bit)&31) & REQUIRED_MASK11)) || \
+ (((bit)>>5)==12 && (1UL<<((bit)&31) & REQUIRED_MASK12)) || \
+ (((bit)>>5)==13 && (1UL<<((bit)&31) & REQUIRED_MASK13)) || \
+ (((bit)>>5)==14 && (1UL<<((bit)&31) & REQUIRED_MASK14)) )
#define DISABLED_MASK_BIT_SET(bit) \
- ( (((bit)>>5)==0 && (1UL<<((bit)&31) & DISABLED_MASK0)) || \
- (((bit)>>5)==1 && (1UL<<((bit)&31) & DISABLED_MASK1)) || \
- (((bit)>>5)==2 && (1UL<<((bit)&31) & DISABLED_MASK2)) || \
- (((bit)>>5)==3 && (1UL<<((bit)&31) & DISABLED_MASK3)) || \
- (((bit)>>5)==4 && (1UL<<((bit)&31) & DISABLED_MASK4)) || \
- (((bit)>>5)==5 && (1UL<<((bit)&31) & DISABLED_MASK5)) || \
- (((bit)>>5)==6 && (1UL<<((bit)&31) & DISABLED_MASK6)) || \
- (((bit)>>5)==7 && (1UL<<((bit)&31) & DISABLED_MASK7)) || \
- (((bit)>>5)==8 && (1UL<<((bit)&31) & DISABLED_MASK8)) || \
- (((bit)>>5)==9 && (1UL<<((bit)&31) & DISABLED_MASK9)) )
+ ( (((bit)>>5)==0 && (1UL<<((bit)&31) & DISABLED_MASK0 )) || \
+ (((bit)>>5)==1 && (1UL<<((bit)&31) & DISABLED_MASK1 )) || \
+ (((bit)>>5)==2 && (1UL<<((bit)&31) & DISABLED_MASK2 )) || \
+ (((bit)>>5)==3 && (1UL<<((bit)&31) & DISABLED_MASK3 )) || \
+ (((bit)>>5)==4 && (1UL<<((bit)&31) & DISABLED_MASK4 )) || \
+ (((bit)>>5)==5 && (1UL<<((bit)&31) & DISABLED_MASK5 )) || \
+ (((bit)>>5)==6 && (1UL<<((bit)&31) & DISABLED_MASK6 )) || \
+ (((bit)>>5)==7 && (1UL<<((bit)&31) & DISABLED_MASK7 )) || \
+ (((bit)>>5)==8 && (1UL<<((bit)&31) & DISABLED_MASK8 )) || \
+ (((bit)>>5)==9 && (1UL<<((bit)&31) & DISABLED_MASK9 )) || \
+ (((bit)>>5)==10 && (1UL<<((bit)&31) & DISABLED_MASK10)) || \
+ (((bit)>>5)==11 && (1UL<<((bit)&31) & DISABLED_MASK11)) || \
+ (((bit)>>5)==12 && (1UL<<((bit)&31) & DISABLED_MASK12)) || \
+ (((bit)>>5)==13 && (1UL<<((bit)&31) & DISABLED_MASK13)) || \
+ (((bit)>>5)==14 && (1UL<<((bit)&31) & DISABLED_MASK14)) )
#define cpu_has(c, bit) \
(__builtin_constant_p(bit) && REQUIRED_MASK_BIT_SET(bit) ? 1 : \
diff -puN arch/x86/include/asm/disabled-features.h~pkeys-01-cpuid arch/x86/include/asm/disabled-features.h
--- a/arch/x86/include/asm/disabled-features.h~pkeys-01-cpuid 2016-01-06 15:50:04.311097422 -0800
+++ b/arch/x86/include/asm/disabled-features.h 2016-01-06 15:50:04.318097738 -0800
@@ -28,6 +28,14 @@
# define DISABLE_CENTAUR_MCR 0
#endif /* CONFIG_X86_64 */
+#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
+# define DISABLE_PKU (1<<(X86_FEATURE_PKU))
+# define DISABLE_OSPKE (1<<(X86_FEATURE_OSPKE))
+#else
+# define DISABLE_PKU 0
+# define DISABLE_OSPKE 0
+#endif /* CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS */
+
/*
* Make sure to add features to the correct mask
*/
@@ -41,5 +49,10 @@
#define DISABLED_MASK7 0
#define DISABLED_MASK8 0
#define DISABLED_MASK9 (DISABLE_MPX)
+#define DISABLED_MASK10 0
+#define DISABLED_MASK11 0
+#define DISABLED_MASK12 0
+#define DISABLED_MASK13 0
+#define DISABLED_MASK14 (DISABLE_PKU|DISABLE_OSPKE)
#endif /* _ASM_X86_DISABLED_FEATURES_H */
diff -puN arch/x86/include/asm/required-features.h~pkeys-01-cpuid arch/x86/include/asm/required-features.h
--- a/arch/x86/include/asm/required-features.h~pkeys-01-cpuid 2016-01-06 15:50:04.313097512 -0800
+++ b/arch/x86/include/asm/required-features.h 2016-01-06 15:50:04.318097738 -0800
@@ -92,5 +92,10 @@
#define REQUIRED_MASK7 0
#define REQUIRED_MASK8 0
#define REQUIRED_MASK9 0
+#define REQUIRED_MASK10 0
+#define REQUIRED_MASK11 0
+#define REQUIRED_MASK12 0
+#define REQUIRED_MASK13 0
+#define REQUIRED_MASK14 0
#endif /* _ASM_X86_REQUIRED_FEATURES_H */
diff -puN arch/x86/kernel/cpu/common.c~pkeys-01-cpuid arch/x86/kernel/cpu/common.c
--- a/arch/x86/kernel/cpu/common.c~pkeys-01-cpuid 2016-01-06 15:50:04.314097557 -0800
+++ b/arch/x86/kernel/cpu/common.c 2016-01-06 15:50:04.319097783 -0800
@@ -619,6 +619,7 @@ void get_cpu_cap(struct cpuinfo_x86 *c)
cpuid_count(0x00000007, 0, &eax, &ebx, &ecx, &edx);
c->x86_capability[9] = ebx;
+ c->x86_capability[14] = ecx;
}
/* Extended state features: level 0x0000000d */
_
--
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next prev parent reply other threads:[~2016-01-07 0:01 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-07 0:01 [PATCH 00/31] x86: Memory Protection Keys (v8) Dave Hansen
2016-01-07 0:01 ` [PATCH 01/31] mm, gup: introduce concept of "foreign" get_user_pages() Dave Hansen
2016-01-13 19:00 ` Vlastimil Babka
2016-01-13 19:16 ` Dave Hansen
2016-01-07 0:01 ` [PATCH 02/31] x86, fpu: add placeholder for Processor Trace XSAVE state Dave Hansen
2016-01-07 0:01 ` [PATCH 03/31] x86, pkeys: Add Kconfig option Dave Hansen
2016-01-07 0:01 ` Dave Hansen [this message]
2016-01-07 0:01 ` [PATCH 05/31] x86, pkeys: define new CR4 bit Dave Hansen
2016-01-07 0:01 ` [PATCH 06/31] x86, pkeys: add PKRU xsave fields and data structure(s) Dave Hansen
2016-01-07 0:01 ` [PATCH 07/31] x86, pkeys: PTE bits for storing protection key Dave Hansen
2016-01-07 0:01 ` [PATCH 08/31] x86, pkeys: new page fault error code bit: PF_PK Dave Hansen
2016-01-07 0:01 ` [PATCH 09/31] x86, pkeys: store protection in high VMA flags Dave Hansen
2016-01-07 0:01 ` [PATCH 10/31] x86, pkeys: arch-specific protection bits Dave Hansen
2016-01-08 19:31 ` Thomas Gleixner
2016-01-07 0:01 ` [PATCH 11/31] x86, pkeys: pass VMA down in to fault signal generation code Dave Hansen
2016-01-07 0:01 ` [PATCH 12/31] signals, pkeys: notify userspace about protection key faults Dave Hansen
2016-01-07 0:01 ` [PATCH 13/31] x86, pkeys: fill in pkey field in siginfo Dave Hansen
2016-01-07 0:01 ` [PATCH 14/31] x86, pkeys: add functions to fetch PKRU Dave Hansen
2016-01-08 19:32 ` Thomas Gleixner
2016-01-07 0:01 ` [PATCH 15/31] mm: factor out VMA fault permission checking Dave Hansen
2016-01-07 0:01 ` [PATCH 16/31] x86, mm: simplify get_user_pages() PTE bit handling Dave Hansen
2016-01-07 0:01 ` [PATCH 17/31] x86, pkeys: check VMAs and PTEs for protection keys Dave Hansen
2016-01-07 0:01 ` [PATCH 18/31] mm: add gup flag to indicate "foreign" mm access Dave Hansen
2016-01-07 0:01 ` [PATCH 19/31] x86, pkeys: optimize fault handling in access_error() Dave Hansen
2016-01-07 0:01 ` [PATCH 20/31] x86, pkeys: differentiate instruction fetches Dave Hansen
2016-01-07 0:01 ` [PATCH 21/31] x86, pkeys: dump PKRU with other kernel registers Dave Hansen
2016-01-07 0:01 ` [PATCH 22/31] x86, pkeys: dump pkey from VMA in /proc/pid/smaps Dave Hansen
2016-01-07 0:01 ` [PATCH 23/31] x86, pkeys: add Kconfig prompt to existing config option Dave Hansen
2016-01-07 0:01 ` [PATCH 24/31] x86, pkeys: actually enable Memory Protection Keys in CPU Dave Hansen
2016-01-07 0:01 ` [PATCH 25/31] mm, multi-arch: pass a protection key in to calc_vm_flag_bits() Dave Hansen
2016-01-07 0:01 ` [PATCH 26/31] x86, pkeys: add arch_validate_pkey() Dave Hansen
2016-01-08 19:34 ` Thomas Gleixner
2016-01-07 0:01 ` [PATCH 27/31] x86: separate out LDT init from context init Dave Hansen
2016-01-07 0:01 ` [PATCH 28/31] x86, fpu: allow setting of XSAVE state Dave Hansen
2016-01-07 0:01 ` [PATCH 29/31] x86, pkeys: allow kernel to modify user pkey rights register Dave Hansen
2016-01-08 19:40 ` Thomas Gleixner
2016-01-07 0:01 ` [PATCH 30/31] x86, pkeys: create an x86 arch_calc_vm_prot_bits() for VMA flags Dave Hansen
2016-01-08 19:40 ` Thomas Gleixner
2016-01-07 0:01 ` [PATCH 31/31] x86, pkeys: execute-only support Dave Hansen
2016-01-07 21:02 ` Kees Cook
2016-01-07 22:25 ` Dave Hansen
2016-01-07 21:10 ` Andy Lutomirski
2016-01-07 22:13 ` Dave Hansen
2016-01-07 22:44 ` Andy Lutomirski
2016-01-08 19:51 ` Thomas Gleixner
2016-01-29 18:16 [PATCH 00/31] x86: Memory Protection Keys (v9) Dave Hansen
2016-01-29 18:16 ` [PATCH 04/31] x86, pkeys: cpuid bit definition Dave Hansen
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