From: Dave Hansen <dave@sr71.net>
To: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org, x86@kernel.org,
torvalds@linux-foundation.org, Dave Hansen <dave@sr71.net>,
dave.hansen@linux.intel.com
Subject: [PATCH 07/31] x86, pkeys: PTE bits for storing protection key
Date: Fri, 29 Jan 2016 10:16:52 -0800 [thread overview]
Message-ID: <20160129181652.3A6B9C06@viggo.jf.intel.com> (raw)
In-Reply-To: <20160129181642.98E7D468@viggo.jf.intel.com>
From: Dave Hansen <dave.hansen@linux.intel.com>
Previous documentation has referred to these 4 bits as "ignored".
That means that software could have made use of them. But, as
far as I know, the kernel never used them.
They are still ignored when protection keys is not enabled, so
they could theoretically still get used for software purposes.
We also implement "empty" versions so that code that references
to them can be optimized away by the compiler when the config
option is not enabled.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
---
b/arch/x86/include/asm/pgtable_types.h | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)
diff -puN arch/x86/include/asm/pgtable_types.h~pkeys-04-ptebits arch/x86/include/asm/pgtable_types.h
--- a/arch/x86/include/asm/pgtable_types.h~pkeys-04-ptebits 2016-01-28 15:52:19.366358352 -0800
+++ b/arch/x86/include/asm/pgtable_types.h 2016-01-28 15:52:19.369358489 -0800
@@ -20,13 +20,18 @@
#define _PAGE_BIT_SOFTW2 10 /* " */
#define _PAGE_BIT_SOFTW3 11 /* " */
#define _PAGE_BIT_PAT_LARGE 12 /* On 2MB or 1GB pages */
+#define _PAGE_BIT_SOFTW4 58 /* available for programmer */
+#define _PAGE_BIT_PKEY_BIT0 59 /* Protection Keys, bit 1/4 */
+#define _PAGE_BIT_PKEY_BIT1 60 /* Protection Keys, bit 2/4 */
+#define _PAGE_BIT_PKEY_BIT2 61 /* Protection Keys, bit 3/4 */
+#define _PAGE_BIT_PKEY_BIT3 62 /* Protection Keys, bit 4/4 */
+#define _PAGE_BIT_NX 63 /* No execute: only valid after cpuid check */
+
#define _PAGE_BIT_SPECIAL _PAGE_BIT_SOFTW1
#define _PAGE_BIT_CPA_TEST _PAGE_BIT_SOFTW1
#define _PAGE_BIT_HIDDEN _PAGE_BIT_SOFTW3 /* hidden by kmemcheck */
#define _PAGE_BIT_SOFT_DIRTY _PAGE_BIT_SOFTW3 /* software dirty tracking */
-#define _PAGE_BIT_SOFTW4 58 /* available for programmer */
-#define _PAGE_BIT_DEVMAP _PAGE_BIT_SOFTW4
-#define _PAGE_BIT_NX 63 /* No execute: only valid after cpuid check */
+#define _PAGE_BIT_DEVMAP _PAGE_BIT_SOFTW4
/* If _PAGE_BIT_PRESENT is clear, we use these: */
/* - if the user mapped it with PROT_NONE; pte_present gives true */
@@ -47,6 +52,17 @@
#define _PAGE_PAT_LARGE (_AT(pteval_t, 1) << _PAGE_BIT_PAT_LARGE)
#define _PAGE_SPECIAL (_AT(pteval_t, 1) << _PAGE_BIT_SPECIAL)
#define _PAGE_CPA_TEST (_AT(pteval_t, 1) << _PAGE_BIT_CPA_TEST)
+#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
+#define _PAGE_PKEY_BIT0 (_AT(pteval_t, 1) << _PAGE_BIT_PKEY_BIT0)
+#define _PAGE_PKEY_BIT1 (_AT(pteval_t, 1) << _PAGE_BIT_PKEY_BIT1)
+#define _PAGE_PKEY_BIT2 (_AT(pteval_t, 1) << _PAGE_BIT_PKEY_BIT2)
+#define _PAGE_PKEY_BIT3 (_AT(pteval_t, 1) << _PAGE_BIT_PKEY_BIT3)
+#else
+#define _PAGE_PKEY_BIT0 (_AT(pteval_t, 0))
+#define _PAGE_PKEY_BIT1 (_AT(pteval_t, 0))
+#define _PAGE_PKEY_BIT2 (_AT(pteval_t, 0))
+#define _PAGE_PKEY_BIT3 (_AT(pteval_t, 0))
+#endif
#define __HAVE_ARCH_PTE_SPECIAL
#ifdef CONFIG_KMEMCHECK
_
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next prev parent reply other threads:[~2016-01-29 18:17 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-29 18:16 [PATCH 00/31] x86: Memory Protection Keys (v9) Dave Hansen
2016-01-29 18:16 ` [PATCH 01/31] mm, gup: introduce concept of "foreign" get_user_pages() Dave Hansen
2016-02-09 12:46 ` Ingo Molnar
2016-02-09 13:06 ` Ingo Molnar
2016-02-09 15:15 ` Dave Hansen
2016-01-29 18:16 ` [PATCH 02/31] x86, fpu: add placeholder for Processor Trace XSAVE state Dave Hansen
2016-01-29 18:16 ` [PATCH 03/31] x86, pkeys: Add Kconfig option Dave Hansen
2016-01-29 18:16 ` [PATCH 04/31] x86, pkeys: cpuid bit definition Dave Hansen
2016-01-29 18:16 ` [PATCH 05/31] x86, pkeys: define new CR4 bit Dave Hansen
2016-01-29 18:16 ` [PATCH 06/31] x86, pkeys: add PKRU xsave fields and data structure(s) Dave Hansen
2016-01-29 18:16 ` Dave Hansen [this message]
2016-01-29 18:16 ` [PATCH 08/31] x86, pkeys: new page fault error code bit: PF_PK Dave Hansen
2016-01-29 18:16 ` [PATCH 09/31] x86, pkeys: store protection in high VMA flags Dave Hansen
2016-01-29 18:16 ` [PATCH 10/31] x86, pkeys: arch-specific protection bits Dave Hansen
2016-01-29 18:16 ` [PATCH 11/31] x86, pkeys: pass VMA down in to fault signal generation code Dave Hansen
2016-01-29 18:16 ` [PATCH 12/31] signals, pkeys: notify userspace about protection key faults Dave Hansen
2016-01-29 18:17 ` [PATCH 13/31] x86, pkeys: fill in pkey field in siginfo Dave Hansen
2016-01-29 18:17 ` [PATCH 14/31] x86, pkeys: add functions to fetch PKRU Dave Hansen
2016-01-29 18:17 ` [PATCH 15/31] mm: factor out VMA fault permission checking Dave Hansen
2016-01-29 18:17 ` [PATCH 16/31] x86, mm: simplify get_user_pages() PTE bit handling Dave Hansen
2016-01-29 18:17 ` [PATCH 17/31] x86, pkeys: check VMAs and PTEs for protection keys Dave Hansen
2016-01-29 18:17 ` [PATCH 18/31] mm: do not enforce PKEY permissions on "foreign" mm access Dave Hansen
2016-01-29 18:17 ` [PATCH 19/31] x86, pkeys: optimize fault handling in access_error() Dave Hansen
2016-01-29 18:17 ` [PATCH 20/31] x86, pkeys: differentiate instruction fetches Dave Hansen
2016-01-29 18:17 ` [PATCH 21/31] x86, pkeys: dump PKRU with other kernel registers Dave Hansen
2016-01-29 18:17 ` [PATCH 22/31] x86, pkeys: dump pkey from VMA in /proc/pid/smaps Dave Hansen
2016-02-02 16:11 ` Vlastimil Babka
2016-02-02 19:04 ` Dave Hansen
2016-01-29 18:17 ` [PATCH 23/31] x86, pkeys: add Kconfig prompt to existing config option Dave Hansen
2016-01-29 18:17 ` [PATCH 24/31] x86, pkeys: actually enable Memory Protection Keys in CPU Dave Hansen
2016-01-29 18:17 ` [PATCH 25/31] mm, multi-arch: pass a protection key in to calc_vm_flag_bits() Dave Hansen
2016-01-29 18:17 ` [PATCH 26/31] x86, pkeys: add arch_validate_pkey() Dave Hansen
2016-01-29 18:17 ` [PATCH 27/31] x86: separate out LDT init from context init Dave Hansen
2016-01-29 18:17 ` [PATCH 28/31] x86, fpu: allow setting of XSAVE state Dave Hansen
2016-01-29 18:17 ` [PATCH 29/31] x86, pkeys: allow kernel to modify user pkey rights register Dave Hansen
2016-01-29 18:17 ` [PATCH 30/31] x86, pkeys: create an x86 arch_calc_vm_prot_bits() for VMA flags Dave Hansen
2016-01-29 18:17 ` [PATCH 31/31] x86, pkeys: execute-only support Dave Hansen
-- strict thread matches above, loose matches on Subject: below --
2016-01-07 0:01 [PATCH 00/31] x86: Memory Protection Keys (v8) Dave Hansen
2016-01-07 0:01 ` [PATCH 07/31] x86, pkeys: PTE bits for storing protection key Dave Hansen
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