Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1321970

[PATCH 08/31] x86, pkeys: new page fault error code bit: PF_PK

Show all headers | View raw

From: Dave Hansen <dave.hansen@linux.intel.com>

Note: "PK" is how the Intel SDM refers to this bit, so we also
use that nomenclature.

This only defines the bit, it does not plumb it anywhere to be
handled.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
---

 b/arch/x86/mm/fault.c |    8 ++++++++
 1 file changed, 8 insertions(+)

diff -puN arch/x86/mm/fault.c~pkeys-05-pfec arch/x86/mm/fault.c
--- a/arch/x86/mm/fault.c~pkeys-05-pfec	2016-01-28 15:52:19.775377103 -0800
+++ b/arch/x86/mm/fault.c	2016-01-28 15:52:19.778377241 -0800
@@ -33,6 +33,7 @@
  *   bit 2 ==	 0: kernel-mode access	1: user-mode access
  *   bit 3 ==				1: use of reserved bit detected
  *   bit 4 ==				1: fault was an instruction fetch
+ *   bit 5 ==				1: protection keys block access
  */
 enum x86_pf_error_code {
 
@@ -41,6 +42,7 @@ enum x86_pf_error_code {
 	PF_USER		=		1 << 2,
 	PF_RSVD		=		1 << 3,
 	PF_INSTR	=		1 << 4,
+	PF_PK		=		1 << 5,
 };
 
 /*
@@ -916,6 +918,12 @@ static int spurious_fault_check(unsigned
 
 	if ((error_code & PF_INSTR) && !pte_exec(*pte))
 		return 0;
+	/*
+	 * Note: We do not do lazy flushing on protection key
+	 * changes, so no spurious fault will ever set PF_PK.
+	 */
+	if ((error_code & PF_PK))
+		return 1;
 
 	return 1;
 }
_

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH 00/31] x86: Memory Protection Keys (v9) Dave Hansen <dave@sr71.net> - 2016-01-29 19:20 +0100
  [PATCH 21/31] x86, pkeys: dump PKRU with other kernel registers Dave Hansen <dave@sr71.net> - 2016-01-29 19:20 +0100
  [PATCH 26/31] x86, pkeys: add arch_validate_pkey() Dave Hansen <dave@sr71.net> - 2016-01-29 19:20 +0100
  [PATCH 29/31] x86, pkeys: allow kernel to modify user pkey rights register Dave Hansen <dave@sr71.net> - 2016-01-29 19:20 +0100
  [PATCH 03/31] x86, pkeys: Add Kconfig option Dave Hansen <dave@sr71.net> - 2016-01-29 19:20 +0100
  [PATCH 09/31] x86, pkeys: store protection in high VMA flags Dave Hansen <dave@sr71.net> - 2016-01-29 19:20 +0100
  [PATCH 05/31] x86, pkeys: define new CR4 bit Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 23/31] x86, pkeys: add Kconfig prompt to existing config option Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 12/31] signals, pkeys: notify userspace about protection key faults Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 24/31] x86, pkeys: actually enable Memory Protection Keys in CPU Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 15/31] mm: factor out VMA fault permission checking Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 20/31] x86, pkeys: differentiate instruction fetches Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 18/31] mm: do not enforce PKEY permissions on "foreign" mm access Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 08/31] x86, pkeys: new page fault error code bit: PF_PK Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 14/31] x86, pkeys: add functions to fetch PKRU Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 04/31] x86, pkeys: cpuid bit definition Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 10/31] x86, pkeys: arch-specific protection bits Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 13/31] x86, pkeys: fill in pkey field in siginfo Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 25/31] mm, multi-arch: pass a protection key in to calc_vm_flag_bits() Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 17/31] x86, pkeys: check VMAs and PTEs for protection keys Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 07/31] x86, pkeys: PTE bits for storing protection key Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 02/31] x86, fpu: add placeholder for Processor Trace XSAVE state Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 16/31] x86, mm: simplify get_user_pages() PTE bit handling Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 11/31] x86, pkeys: pass VMA down in to fault signal generation code Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
  [PATCH 22/31] x86, pkeys: dump pkey from VMA in /proc/pid/smaps Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100
    Re: [PATCH 22/31] x86, pkeys: dump pkey from VMA in /proc/pid/smaps Vlastimil Babka <vbabka@suse.cz> - 2016-02-02 17:20 +0100
      Re: [PATCH 22/31] x86, pkeys: dump pkey from VMA in /proc/pid/smaps Dave Hansen <dave@sr71.net> - 2016-02-02 20:10 +0100
  [PATCH 06/31] x86, pkeys: add PKRU xsave fields and data structure(s) Dave Hansen <dave@sr71.net> - 2016-01-29 19:30 +0100

csiph-web