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 07/34] x86, pkeys: PTE bits for storing protection key Date: Thu, 03 Dec 2015 17:14:34 -0800 [thread overview] Message-ID: <20151204011434.CB5FDF0F@viggo.jf.intel.com> (raw) In-Reply-To: <20151204011424.8A36E365@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 | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) 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 2015-12-03 16:21:21.207470895 -0800 +++ b/arch/x86/include/asm/pgtable_types.h 2015-12-03 16:21:21.211471076 -0800 @@ -25,7 +25,11 @@ #define _PAGE_BIT_SPLITTING _PAGE_BIT_SOFTW2 /* only valid on a PSE pmd */ #define _PAGE_BIT_HIDDEN _PAGE_BIT_SOFTW3 /* hidden by kmemcheck */ #define _PAGE_BIT_SOFT_DIRTY _PAGE_BIT_SOFTW3 /* software dirty tracking */ -#define _PAGE_BIT_NX 63 /* No execute: only valid after cpuid check */ +#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 */ /* If _PAGE_BIT_PRESENT is clear, we use these: */ /* - if the user mapped it with PROT_NONE; pte_present gives true */ @@ -47,6 +51,17 @@ #define _PAGE_SPECIAL (_AT(pteval_t, 1) << _PAGE_BIT_SPECIAL) #define _PAGE_CPA_TEST (_AT(pteval_t, 1) << _PAGE_BIT_CPA_TEST) #define _PAGE_SPLITTING (_AT(pteval_t, 1) << _PAGE_BIT_SPLITTING) +#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 _
WARNING: multiple messages have this Message-ID (diff)
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 07/34] x86, pkeys: PTE bits for storing protection key Date: Thu, 03 Dec 2015 17:14:34 -0800 [thread overview] Message-ID: <20151204011434.CB5FDF0F@viggo.jf.intel.com> (raw) In-Reply-To: <20151204011424.8A36E365@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 | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) 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 2015-12-03 16:21:21.207470895 -0800 +++ b/arch/x86/include/asm/pgtable_types.h 2015-12-03 16:21:21.211471076 -0800 @@ -25,7 +25,11 @@ #define _PAGE_BIT_SPLITTING _PAGE_BIT_SOFTW2 /* only valid on a PSE pmd */ #define _PAGE_BIT_HIDDEN _PAGE_BIT_SOFTW3 /* hidden by kmemcheck */ #define _PAGE_BIT_SOFT_DIRTY _PAGE_BIT_SOFTW3 /* software dirty tracking */ -#define _PAGE_BIT_NX 63 /* No execute: only valid after cpuid check */ +#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 */ /* If _PAGE_BIT_PRESENT is clear, we use these: */ /* - if the user mapped it with PROT_NONE; pte_present gives true */ @@ -47,6 +51,17 @@ #define _PAGE_SPECIAL (_AT(pteval_t, 1) << _PAGE_BIT_SPECIAL) #define _PAGE_CPA_TEST (_AT(pteval_t, 1) << _PAGE_BIT_CPA_TEST) #define _PAGE_SPLITTING (_AT(pteval_t, 1) << _PAGE_BIT_SPLITTING) +#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 _ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2015-12-04 1:22 UTC|newest] Thread overview: 145+ messages / expand[flat|nested] mbox.gz Atom feed top 2015-12-04 1:14 [PATCH 00/34] x86: Memory Protection Keys (v5) Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` [PATCH 01/34] mm, gup: introduce concept of "foreign" get_user_pages() Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` [PATCH 02/34] x86, fpu: add placeholder for Processor Trace XSAVE state Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` [PATCH 03/34] x86, pkeys: Add Kconfig option Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` [PATCH 04/34] x86, pkeys: cpuid bit definition Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` [PATCH 05/34] x86, pkeys: define new CR4 bit Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` [PATCH 06/34] x86, pkeys: add PKRU xsave fields and data structure(s) Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` Dave Hansen [this message] 2015-12-04 1:14 ` [PATCH 07/34] x86, pkeys: PTE bits for storing protection key Dave Hansen 2015-12-04 1:14 ` [PATCH 08/34] x86, pkeys: new page fault error code bit: PF_PK Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` [PATCH 09/34] x86, pkeys: store protection in high VMA flags Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-08 14:17 ` Thomas Gleixner 2015-12-08 14:17 ` Thomas Gleixner 2015-12-04 1:14 ` [PATCH 10/34] x86, pkeys: arch-specific protection bits Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-08 15:15 ` [PATCH 10/34] x86, pkeys: arch-specific protection bitsy Thomas Gleixner 2015-12-08 15:15 ` Thomas Gleixner 2015-12-08 16:34 ` Dave Hansen 2015-12-08 16:34 ` Dave Hansen 2015-12-08 17:24 ` Thomas Gleixner 2015-12-08 17:24 ` Thomas Gleixner 2015-12-08 18:06 ` Dave Hansen 2015-12-08 18:29 ` Thomas Gleixner 2015-12-08 18:29 ` Thomas Gleixner 2015-12-08 18:35 ` Thomas Gleixner 2015-12-08 18:35 ` Thomas Gleixner 2015-12-04 1:14 ` [PATCH 11/34] x86, pkeys: pass VMA down in to fault signal generation code Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` [PATCH 12/34] signals, pkeys: notify userspace about protection key faults Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` [PATCH 13/34] x86, pkeys: fill in pkey field in siginfo Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` [PATCH 14/34] x86, pkeys: add functions to fetch PKRU Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-08 15:18 ` Thomas Gleixner 2015-12-08 15:18 ` Thomas Gleixner 2015-12-04 1:14 ` [PATCH 15/34] mm: factor out VMA fault permission checking Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-08 17:26 ` Thomas Gleixner 2015-12-08 17:26 ` Thomas Gleixner 2015-12-04 1:14 ` [PATCH 16/34] x86, mm: simplify get_user_pages() PTE bit handling Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-08 18:01 ` Thomas Gleixner 2015-12-08 18:01 ` Thomas Gleixner 2015-12-08 18:30 ` Dave Hansen 2015-12-08 18:30 ` Dave Hansen 2015-12-04 1:14 ` [PATCH 17/34] x86, pkeys: check VMAs and PTEs for protection keys Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-08 18:11 ` Thomas Gleixner 2015-12-08 18:11 ` Thomas Gleixner 2015-12-04 1:14 ` [PATCH 18/34] mm: add gup flag to indicate "foreign" mm access Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` [PATCH 19/34] x86, pkeys: optimize fault handling in access_error() Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-08 18:14 ` Thomas Gleixner 2015-12-08 18:14 ` Thomas Gleixner 2015-12-04 1:14 ` [PATCH 20/34] x86, pkeys: differentiate instruction fetches Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-08 18:17 ` Thomas Gleixner 2015-12-08 18:17 ` Thomas Gleixner 2015-12-04 1:14 ` [PATCH 21/34] x86, pkeys: dump PKRU with other kernel registers Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-08 18:19 ` Thomas Gleixner 2015-12-08 18:19 ` Thomas Gleixner 2015-12-04 1:14 ` [PATCH 22/34] x86, pkeys: dump PTE pkey in /proc/pid/smaps Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-08 18:20 ` Thomas Gleixner 2015-12-08 18:20 ` Thomas Gleixner 2015-12-04 1:14 ` [PATCH 23/34] x86, pkeys: add Kconfig prompt to existing config option Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-08 18:21 ` Thomas Gleixner 2015-12-08 18:21 ` Thomas Gleixner 2015-12-04 1:14 ` [PATCH 24/34] mm, multi-arch: pass a protection key in to calc_vm_flag_bits() Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-04 1:14 ` [PATCH 25/34] x86, pkeys: add arch_validate_pkey() Dave Hansen 2015-12-04 1:14 ` Dave Hansen 2015-12-08 18:39 ` Thomas Gleixner 2015-12-08 18:39 ` Thomas Gleixner 2015-12-04 1:15 ` [PATCH 26/34] mm: implement new mprotect_key() system call Dave Hansen 2015-12-04 1:15 ` Dave Hansen 2015-12-05 6:50 ` Michael Kerrisk (man-pages) 2015-12-05 6:50 ` Michael Kerrisk (man-pages) 2015-12-05 6:50 ` Michael Kerrisk (man-pages) 2015-12-07 16:44 ` Dave Hansen 2015-12-07 16:44 ` Dave Hansen 2015-12-09 11:08 ` Michael Kerrisk (man-pages) 2015-12-09 11:08 ` Michael Kerrisk (man-pages) 2015-12-09 15:48 ` Dave Hansen 2015-12-09 15:48 ` Dave Hansen 2015-12-09 16:45 ` Michael Kerrisk (man-pages) 2015-12-09 16:45 ` Michael Kerrisk (man-pages) 2015-12-09 16:45 ` Michael Kerrisk (man-pages) 2015-12-09 17:05 ` Dave Hansen 2015-12-09 17:05 ` Dave Hansen 2015-12-09 17:05 ` Dave Hansen 2015-12-11 20:13 ` Michael Kerrisk (man-pages) 2015-12-11 20:13 ` Michael Kerrisk (man-pages) 2015-12-04 1:15 ` [PATCH 27/34] x86, pkeys: make mprotect_key() mask off additional vm_flags Dave Hansen 2015-12-04 1:15 ` Dave Hansen 2015-12-08 18:41 ` Thomas Gleixner 2015-12-08 18:41 ` Thomas Gleixner 2015-12-04 1:15 ` [PATCH 28/34] x86: wire up mprotect_key() system call Dave Hansen 2015-12-04 1:15 ` Dave Hansen 2015-12-08 18:44 ` Thomas Gleixner 2015-12-08 18:44 ` Thomas Gleixner 2015-12-08 18:44 ` Thomas Gleixner 2015-12-08 19:06 ` Dave Hansen 2015-12-08 19:06 ` Dave Hansen 2015-12-08 20:38 ` Thomas Gleixner 2015-12-08 20:38 ` Thomas Gleixner 2015-12-08 20:38 ` Thomas Gleixner 2015-12-04 1:15 ` [PATCH 29/34] x86: separate out LDT init from context init Dave Hansen 2015-12-04 1:15 ` Dave Hansen 2015-12-08 18:45 ` Thomas Gleixner 2015-12-08 18:45 ` Thomas Gleixner 2015-12-04 1:15 ` [PATCH 30/34] x86, fpu: allow setting of XSAVE state Dave Hansen 2015-12-04 1:15 ` Dave Hansen 2015-12-08 18:48 ` Thomas Gleixner 2015-12-08 18:48 ` Thomas Gleixner 2015-12-04 1:15 ` [PATCH 31/34] x86, pkeys: allocation/free syscalls Dave Hansen 2015-12-04 1:15 ` Dave Hansen 2015-12-04 1:15 ` [PATCH 32/34] x86, pkeys: add pkey set/get syscalls Dave Hansen 2015-12-04 1:15 ` Dave Hansen 2015-12-04 1:15 ` [PATCH 33/34] x86, pkeys: actually enable Memory Protection Keys in CPU Dave Hansen 2015-12-04 1:15 ` Dave Hansen 2015-12-04 1:15 ` [PATCH 34/34] x86, pkeys: Documentation Dave Hansen 2015-12-04 1:15 ` Dave Hansen 2015-12-04 23:31 ` [PATCH 00/34] x86: Memory Protection Keys (v5) Andy Lutomirski 2015-12-04 23:31 ` Andy Lutomirski 2015-12-04 23:38 ` Dave Hansen 2015-12-04 23:38 ` Dave Hansen 2015-12-04 23:38 ` Dave Hansen 2015-12-11 20:16 ` Andy Lutomirski 2015-12-11 20:16 ` Andy Lutomirski 2015-12-11 20:16 ` Andy Lutomirski
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20151204011434.CB5FDF0F@viggo.jf.intel.com \ --to=dave@sr71.net \ --cc=dave.hansen@linux.intel.com \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-mm@kvack.org \ --cc=x86@kernel.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.