From: Dave Hansen <dave@sr71.net>
To: dave@sr71.net
Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: [PATCH 03/26] x86, pkeys: cpuid bit definition
Date: Wed, 16 Sep 2015 10:49:04 -0700 [thread overview]
Message-ID: <20150916174904.369049ED@viggo.jf.intel.com> (raw)
In-Reply-To: <20150916174903.E112E464@viggo.jf.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(X86_FEATURE_PKU)
and *not* the CONFIG option.
---
b/arch/x86/include/asm/cpufeature.h | 54 +++++++++++++++++------------
b/arch/x86/include/asm/disabled-features.h | 12 ++++++
b/arch/x86/include/asm/required-features.h | 4 ++
b/arch/x86/kernel/cpu/common.c | 1
4 files changed, 50 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 2015-09-16 10:48:12.424018599 -0700
+++ b/arch/x86/include/asm/cpufeature.h 2015-09-16 10:48:12.433019007 -0700
@@ -12,7 +12,7 @@
#include <asm/disabled-features.h>
#endif
-#define NCAPINTS 13 /* N 32-bit words worth of info */
+#define NCAPINTS 14 /* N 32-bit words worth of info */
#define NBUGINTS 1 /* N 32-bit bug flags */
/*
@@ -254,6 +254,10 @@
/* Intel-defined CPU QoS Sub-leaf, CPUID level 0x0000000F:1 (edx), word 12 */
#define X86_FEATURE_CQM_OCCUP_LLC (12*32+ 0) /* LLC occupancy monitoring if 1 */
+/* Intel-defined CPU features, CPUID level 0x00000007:0 (ecx), word 13 */
+#define X86_FEATURE_PKU (13*32+ 3) /* Protection Keys for Userspace */
+#define X86_FEATURE_OSPKE (13*32+ 4) /* OS Protection Keys Enable */
+
/*
* BUG word(s)
*/
@@ -294,28 +298,36 @@ 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)) )
#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)) )
#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 2015-09-16 10:48:12.426018689 -0700
+++ b/arch/x86/include/asm/disabled-features.h 2015-09-16 10:48:12.433019007 -0700
@@ -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 +49,9 @@
#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 (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 2015-09-16 10:48:12.428018780 -0700
+++ b/arch/x86/include/asm/required-features.h 2015-09-16 10:48:12.433019007 -0700
@@ -92,5 +92,9 @@
#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
#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 2015-09-16 10:48:12.429018825 -0700
+++ b/arch/x86/kernel/cpu/common.c 2015-09-16 10:48:12.434019052 -0700
@@ -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[13] = ecx;
}
/* Extended state features: level 0x0000000d */
_
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next prev parent reply other threads:[~2015-09-16 17:55 UTC|newest]
Thread overview: 86+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-09-16 17:49 [PATCH 00/26] [RFCv2] x86: Memory Protection Keys Dave Hansen
2015-09-16 17:49 ` [PATCH 04/26] x86, pku: define new CR4 bit Dave Hansen
2015-09-16 17:49 ` Dave Hansen [this message]
2015-09-16 17:49 ` [PATCH 01/26] x86, fpu: add placeholder for Processor Trace XSAVE state Dave Hansen
2015-09-16 17:49 ` [PATCH 02/26] x86, pkeys: Add Kconfig option Dave Hansen
2015-09-16 17:49 ` [PATCH 06/26] x86, pkeys: PTE bits for storing protection key Dave Hansen
2015-09-16 17:49 ` [PATCH 05/26] x86, pkey: add PKRU xsave fields and data structure(s) Dave Hansen
2015-09-22 19:53 ` Thomas Gleixner
2015-09-22 19:58 ` Dave Hansen
2015-09-16 17:49 ` [PATCH 07/26] x86, pkeys: new page fault error code bit: PF_PK Dave Hansen
2015-09-16 17:49 ` [PATCH 10/26] x86, pkeys: notify userspace about protection key faults Dave Hansen
2015-09-22 20:03 ` Thomas Gleixner
2015-09-22 20:21 ` Dave Hansen
2015-09-22 20:27 ` Thomas Gleixner
2015-09-22 20:29 ` Dave Hansen
2015-09-23 8:05 ` Ingo Molnar
2015-09-24 9:23 ` Ingo Molnar
2015-09-24 9:30 ` Ingo Molnar
2015-09-24 17:41 ` Dave Hansen
2015-09-25 7:11 ` Ingo Molnar
2015-09-25 23:18 ` Dave Hansen
2015-09-26 6:20 ` Ingo Molnar
2015-09-27 22:39 ` Dave Hansen
2015-09-28 5:59 ` Ingo Molnar
2015-09-24 17:15 ` Dave Hansen
2015-09-28 19:25 ` Christian Borntraeger
2015-09-28 19:32 ` Dave Hansen
2015-09-16 17:49 ` [PATCH 11/26] x86, pkeys: add functions for set/fetch PKRU Dave Hansen
2015-09-22 20:05 ` Thomas Gleixner
2015-09-22 20:22 ` Dave Hansen
2015-09-16 17:49 ` [PATCH 08/26] x86, pkeys: store protection in high VMA flags Dave Hansen
2015-09-16 17:49 ` [PATCH 09/26] x86, pkeys: arch-specific protection bits Dave Hansen
2015-09-16 17:49 ` [PATCH 12/26] mm: factor out VMA fault permission checking Dave Hansen
2015-09-16 17:49 ` [PATCH 13/26] mm: simplify get_user_pages() PTE bit handling Dave Hansen
2015-09-16 17:49 ` [PATCH 14/26] x86, pkeys: check VMAs and PTEs for protection keys Dave Hansen
2015-09-16 17:49 ` [PATCH 17/26] x86, pkeys: dump PTE pkey in /proc/pid/smaps Dave Hansen
2015-09-16 17:49 ` [PATCH 16/26] x86, pkeys: dump PKRU with other kernel registers Dave Hansen
2015-09-16 17:49 ` [PATCH 15/26] x86, pkeys: optimize fault handling in access_error() Dave Hansen
2015-09-16 17:49 ` [PATCH 19/26] [NEWSYSCALL] mm, multi-arch: pass a protection key in to calc_vm_flag_bits() Dave Hansen
2015-09-16 17:49 ` [PATCH 20/26] [NEWSYSCALL] mm: implement new mprotect_pkey() system call Dave Hansen
2015-09-16 17:49 ` [PATCH 18/26] x86, pkeys: add Kconfig prompt to existing config option Dave Hansen
2015-09-16 17:49 ` [PATCH 22/26] [HIJACKPROT] mm: Pass the 4-bit protection key in via PROT_ bits to syscalls Dave Hansen
2015-09-16 17:49 ` [PATCH 21/26] [NEWSYSCALL] x86: wire up mprotect_key() system call Dave Hansen
2015-09-16 17:49 ` [PATCH 24/26] [HIJACKPROT] x86, pkeys: mask off pkeys bits in mprotect() Dave Hansen
2015-09-16 17:49 ` [PATCH 25/26] x86, pkeys: actually enable Memory Protection Keys in CPU Dave Hansen
2015-09-16 17:49 ` [PATCH 23/26] [HIJACKPROT] x86, pkeys: add x86 version of arch_validate_prot() Dave Hansen
2015-09-16 17:49 ` [PATCH 26/26] x86, pkeys: Documentation Dave Hansen
2015-09-20 8:55 ` Ingo Molnar
2015-09-21 4:34 ` Dave Hansen
2015-09-24 9:49 ` Ingo Molnar
2015-09-24 19:10 ` Dave Hansen
2015-09-24 19:17 ` Andy Lutomirski
2015-09-25 7:16 ` Ingo Molnar
2015-09-25 6:15 ` Ingo Molnar
2015-10-01 11:17 ` Ingo Molnar
2015-10-01 20:39 ` Kees Cook
2015-10-01 20:45 ` Andy Lutomirski
2015-10-02 6:23 ` Ingo Molnar
2015-10-02 17:50 ` Dave Hansen
2015-10-03 7:27 ` Ingo Molnar
2015-10-06 23:28 ` Dave Hansen
2015-10-07 7:11 ` Ingo Molnar
2015-10-16 15:12 ` Dave Hansen
2015-10-21 18:55 ` Andy Lutomirski
2015-10-21 19:11 ` Dave Hansen
2015-10-21 23:22 ` Andy Lutomirski
2015-10-01 20:58 ` Dave Hansen
2015-10-01 22:33 ` Dave Hansen
2015-10-01 22:35 ` Kees Cook
2015-10-01 22:39 ` Dave Hansen
2015-10-01 22:48 ` Linus Torvalds
2015-10-01 22:56 ` Dave Hansen
2015-10-02 1:38 ` Linus Torvalds
2015-10-02 18:08 ` Dave Hansen
2015-10-02 7:09 ` Ingo Molnar
2015-10-03 6:59 ` Ingo Molnar
2015-10-02 11:49 ` Paolo Bonzini
2015-10-02 11:58 ` Linus Torvalds
2015-10-02 12:14 ` Paolo Bonzini
2015-10-03 6:46 ` Ingo Molnar
2015-10-01 22:57 ` Andy Lutomirski
2015-10-02 6:09 ` Ingo Molnar
2015-10-03 8:17 ` Ingo Molnar
2015-10-07 20:24 ` Dave Hansen
2015-10-07 20:39 ` Andy Lutomirski
2015-10-07 20:47 ` Dave Hansen
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