Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next

Pull sparc updates from David Miller:

 1) Add support for ADI (Application Data Integrity) found in more
    recent sparc64 cpus. Essentially this is keyed based access to
    virtual memory, and if the key encoded in the virual address is
    wrong you get a trap.

    The mm changes were reviewed by Andrew Morton and others.

    Work by Khalid Aziz.

 2) Validate DAX completion index range properly, from Rob Gardner.

 3) Add proper Kconfig deps for DAX driver. From Guenter Roeck.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next:
  sparc64: Make atomic_xchg() an inline function rather than a macro.
  sparc64: Properly range check DAX completion index
  sparc: Make auxiliary vectors for ADI available on 32-bit as well
  sparc64: Oracle DAX driver depends on SPARC64
  sparc64: Update signal delivery to use new helper functions
  sparc64: Add support for ADI (Application Data Integrity)
  mm: Allow arch code to override copy_highpage()
  mm: Clear arch specific VM flags on protection change
  mm: Add address parameter to arch_validate_prot()
  sparc64: Add auxiliary vectors to report platform ADI properties
  sparc64: Add handler for "Memory Corruption Detected" trap
  sparc64: Add HV fault type handlers for ADI related faults
  sparc64: Add support for ADI register fields, ASIs and traps
  mm, swap: Add infrastructure for saving page metadata on swap
  signals, sparc: Add signal codes for ADI violations

17 files changed, 308 insertions, 4 deletions

diff --git a/arch/sparc/include/asm/adi.h b/arch/sparc/include/asm/adi.h
new file mode 100644
index 0000000..acad0d0
--- /dev/null
+++ b/arch/sparc/include/asm/adi.h
@@ -0,0 +1,6 @@
+#ifndef ___ASM_SPARC_ADI_H
+#define ___ASM_SPARC_ADI_H
+#if defined(__sparc__) && defined(__arch64__)
+#include <asm/adi_64.h>
+#endif
+#endif
diff --git a/arch/sparc/include/asm/adi_64.h b/arch/sparc/include/asm/adi_64.h
new file mode 100644
index 0000000..85f7a76
--- /dev/null
+++ b/arch/sparc/include/asm/adi_64.h
@@ -0,0 +1,47 @@
+/* adi_64.h: ADI related data structures
+ *
+ * Copyright (c) 2016 Oracle and/or its affiliates. All rights reserved.
+ * Author: Khalid Aziz (khalid.aziz@oracle.com)
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ */
+#ifndef __ASM_SPARC64_ADI_H
+#define __ASM_SPARC64_ADI_H
+
+#include <linux/types.h>
+
+#ifndef __ASSEMBLY__
+
+struct adi_caps {
+	__u64 blksz;
+	__u64 nbits;
+	__u64 ue_on_adi;
+};
+
+struct adi_config {
+	bool enabled;
+	struct adi_caps caps;
+};
+
+extern struct adi_config adi_state;
+
+extern void mdesc_adi_init(void);
+
+static inline bool adi_capable(void)
+{
+	return adi_state.enabled;
+}
+
+static inline unsigned long adi_blksize(void)
+{
+	return adi_state.caps.blksz;
+}
+
+static inline unsigned long adi_nbits(void)
+{
+	return adi_state.caps.nbits;
+}
+
+#endif	/* __ASSEMBLY__ */
+
+#endif	/* !(__ASM_SPARC64_ADI_H) */
diff --git a/arch/sparc/include/asm/atomic_64.h b/arch/sparc/include/asm/atomic_64.h
index abad97e..28db058 100644
--- a/arch/sparc/include/asm/atomic_64.h
+++ b/arch/sparc/include/asm/atomic_64.h
@@ -83,7 +83,11 @@ ATOMIC_OPS(xor)
 #define atomic64_add_negative(i, v) (atomic64_add_return(i, v) < 0)
 
 #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
-#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
+static inline int atomic_xchg(atomic_t *v, int new)
+{
+	return xchg(&v->counter, new);
+}
 
 static inline int __atomic_add_unless(atomic_t *v, int a, int u)
 {
diff --git a/arch/sparc/include/asm/elf_64.h b/arch/sparc/include/asm/elf_64.h
index 25340df..7e078bc 100644
--- a/arch/sparc/include/asm/elf_64.h
+++ b/arch/sparc/include/asm/elf_64.h
@@ -10,6 +10,7 @@
 #include <asm/processor.h>
 #include <asm/extable_64.h>
 #include <asm/spitfire.h>
+#include <asm/adi.h>
 
 /*
  * Sparc section types
@@ -215,9 +216,13 @@ extern unsigned int vdso_enabled;
 
 #define	ARCH_DLINFO							\
 do {									\
+	extern struct adi_config adi_state;				\
 	if (vdso_enabled)						\
 		NEW_AUX_ENT(AT_SYSINFO_EHDR,				\
 			    (unsigned long)current->mm->context.vdso);	\
+	NEW_AUX_ENT(AT_ADI_BLKSZ, adi_state.caps.blksz);		\
+	NEW_AUX_ENT(AT_ADI_NBITS, adi_state.caps.nbits);		\
+	NEW_AUX_ENT(AT_ADI_UEONADI, adi_state.caps.ue_on_adi);		\
 } while (0)
 
 struct linux_binprm;
diff --git a/arch/sparc/include/asm/hypervisor.h b/arch/sparc/include/asm/hypervisor.h
index ab9c6b0..08650d5 100644
--- a/arch/sparc/include/asm/hypervisor.h
+++ b/arch/sparc/include/asm/hypervisor.h
@@ -570,6 +570,8 @@ struct hv_fault_status {
 #define HV_FAULT_TYPE_RESV1	13
 #define HV_FAULT_TYPE_UNALIGNED	14
 #define HV_FAULT_TYPE_INV_PGSZ	15
+#define HV_FAULT_TYPE_MCD	17
+#define HV_FAULT_TYPE_MCD_DIS	18
 /* Values 16 --> -2 are reserved.  */
 #define HV_FAULT_TYPE_MULTIPLE	-1
 
diff --git a/arch/sparc/include/asm/mman.h b/arch/sparc/include/asm/mman.h
index 7e94721..f94532f 100644
--- a/arch/sparc/include/asm/mman.h
+++ b/arch/sparc/include/asm/mman.h
@@ -7,5 +7,87 @@
 #ifndef __ASSEMBLY__
 #define arch_mmap_check(addr,len,flags)	sparc_mmap_check(addr,len)
 int sparc_mmap_check(unsigned long addr, unsigned long len);
-#endif
+
+#ifdef CONFIG_SPARC64
+#include <asm/adi_64.h>
+
+static inline void ipi_set_tstate_mcde(void *arg)
+{
+	struct mm_struct *mm = arg;
+
+	/* Set TSTATE_MCDE for the task using address map that ADI has been
+	 * enabled on if the task is running. If not, it will be set
+	 * automatically at the next context switch
+	 */
+	if (current->mm == mm) {
+		struct pt_regs *regs;
+
+		regs = task_pt_regs(current);
+		regs->tstate |= TSTATE_MCDE;
+	}
+}
+
+#define arch_calc_vm_prot_bits(prot, pkey) sparc_calc_vm_prot_bits(prot)
+static inline unsigned long sparc_calc_vm_prot_bits(unsigned long prot)
+{
+	if (adi_capable() && (prot & PROT_ADI)) {
+		struct pt_regs *regs;
+
+		if (!current->mm->context.adi) {
+			regs = task_pt_regs(current);
+			regs->tstate |= TSTATE_MCDE;
+			current->mm->context.adi = true;
+			on_each_cpu_mask(mm_cpumask(current->mm),
+					 ipi_set_tstate_mcde, current->mm, 0);
+		}
+		return VM_SPARC_ADI;
+	} else {
+		return 0;
+	}
+}
+
+#define arch_vm_get_page_prot(vm_flags) sparc_vm_get_page_prot(vm_flags)
+static inline pgprot_t sparc_vm_get_page_prot(unsigned long vm_flags)
+{
+	return (vm_flags & VM_SPARC_ADI) ? __pgprot(_PAGE_MCD_4V) : __pgprot(0);
+}
+
+#define arch_validate_prot(prot, addr) sparc_validate_prot(prot, addr)
+static inline int sparc_validate_prot(unsigned long prot, unsigned long addr)
+{
+	if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM | PROT_ADI))
+		return 0;
+	if (prot & PROT_ADI) {
+		if (!adi_capable())
+			return 0;
+
+		if (addr) {
+			struct vm_area_struct *vma;
+
+			vma = find_vma(current->mm, addr);
+			if (vma) {
+				/* ADI can not be enabled on PFN
+				 * mapped pages
+				 */
+				if (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP))
+					return 0;
+
+				/* Mergeable pages can become unmergeable
+				 * if ADI is enabled on them even if they
+				 * have identical data on them. This can be
+				 * because ADI enabled pages with identical
+				 * data may still not have identical ADI
+				 * tags on them. Disallow ADI on mergeable
+				 * pages.
+				 */
+				if (vma->vm_flags & VM_MERGEABLE)
+					return 0;
+			}
+		}
+	}
+	return 1;
+}
+#endif /* CONFIG_SPARC64 */
+
+#endif /* __ASSEMBLY__ */
 #endif /* __SPARC_MMAN_H__ */
diff --git a/arch/sparc/include/asm/mmu_64.h b/arch/sparc/include/asm/mmu_64.h
index ad4fb93..7e2704c 100644
--- a/arch/sparc/include/asm/mmu_64.h
+++ b/arch/sparc/include/asm/mmu_64.h
@@ -90,6 +90,20 @@ struct tsb_config {
 #define MM_NUM_TSBS	1
 #endif
 
+/* ADI tags are stored when a page is swapped out and the storage for
+ * tags is allocated dynamically. There is a tag storage descriptor
+ * associated with each set of tag storage pages. Tag storage descriptors
+ * are allocated dynamically. Since kernel will allocate a full page for
+ * each tag storage descriptor, we can store up to
+ * PAGE_SIZE/sizeof(tag storage descriptor) descriptors on that page.
+ */
+typedef struct {
+	unsigned long	start;		/* Start address for this tag storage */
+	unsigned long	end;		/* Last address for tag storage */
+	unsigned char	*tags;		/* Where the tags are */
+	unsigned long	tag_users;	/* number of references to descriptor */
+} tag_storage_desc_t;
+
 typedef struct {
 	spinlock_t		lock;
 	unsigned long		sparc64_ctx_val;
@@ -98,6 +112,9 @@ typedef struct {
 	struct tsb_config	tsb_block[MM_NUM_TSBS];
 	struct hv_tsb_descr	tsb_descr[MM_NUM_TSBS];
 	void			*vdso;
+	bool			adi;
+	tag_storage_desc_t	*tag_store;
+	spinlock_t		tag_lock;
 } mm_context_t;
 
 #endif /* !__ASSEMBLY__ */
diff --git a/arch/sparc/include/asm/mmu_context_64.h b/arch/sparc/include/asm/mmu_context_64.h
index b361702..312fcee 100644
--- a/arch/sparc/include/asm/mmu_context_64.h
+++ b/arch/sparc/include/asm/mmu_context_64.h
@@ -9,8 +9,10 @@
 #include <linux/spinlock.h>
 #include <linux/mm_types.h>
 #include <linux/smp.h>
+#include <linux/sched.h>
 
 #include <asm/spitfire.h>
+#include <asm/adi_64.h>
 #include <asm-generic/mm_hooks.h>
 #include <asm/percpu.h>
 
@@ -136,6 +138,55 @@ static inline void switch_mm(struct mm_struct *old_mm, struct mm_struct *mm, str
 
 #define deactivate_mm(tsk,mm)	do { } while (0)
 #define activate_mm(active_mm, mm) switch_mm(active_mm, mm, NULL)
+
+#define  __HAVE_ARCH_START_CONTEXT_SWITCH
+static inline void arch_start_context_switch(struct task_struct *prev)
+{
+	/* Save the current state of MCDPER register for the process
+	 * we are switching from
+	 */
+	if (adi_capable()) {
+		register unsigned long tmp_mcdper;
+
+		__asm__ __volatile__(
+			".word 0x83438000\n\t"	/* rd  %mcdper, %g1 */
+			"mov %%g1, %0\n\t"
+			: "=r" (tmp_mcdper)
+			:
+			: "g1");
+		if (tmp_mcdper)
+			set_tsk_thread_flag(prev, TIF_MCDPER);
+		else
+			clear_tsk_thread_flag(prev, TIF_MCDPER);
+	}
+}
+
+#define finish_arch_post_lock_switch	finish_arch_post_lock_switch
+static inline void finish_arch_post_lock_switch(void)
+{
+	/* Restore the state of MCDPER register for the new process
+	 * just switched to.
+	 */
+	if (adi_capable()) {
+		register unsigned long tmp_mcdper;
+
+		tmp_mcdper = test_thread_flag(TIF_MCDPER);
+		__asm__ __volatile__(
+			"mov %0, %%g1\n\t"
+			".word 0x9d800001\n\t"	/* wr %g0, %g1, %mcdper" */
+			".word 0xaf902001\n\t"	/* wrpr %g0, 1, %pmcdper */
+			:
+			: "ir" (tmp_mcdper)
+			: "g1");
+		if (current && current->mm && current->mm->context.adi) {
+			struct pt_regs *regs;
+
+			regs = task_pt_regs(current);
+			regs->tstate |= TSTATE_MCDE;
+		}
+	}
+}
+
 #endif /* !(__ASSEMBLY__) */
 
 #endif /* !(__SPARC64_MMU_CONTEXT_H) */
diff --git a/arch/sparc/include/asm/page_64.h b/arch/sparc/include/asm/page_64.h
index c28379b..e80f2d5 100644
--- a/arch/sparc/include/asm/page_64.h
+++ b/arch/sparc/include/asm/page_64.h
@@ -48,6 +48,12 @@ struct page;
 void clear_user_page(void *addr, unsigned long vaddr, struct page *page);
 #define copy_page(X,Y)	memcpy((void *)(X), (void *)(Y), PAGE_SIZE)
 void copy_user_page(void *to, void *from, unsigned long vaddr, struct page *topage);
+#define __HAVE_ARCH_COPY_USER_HIGHPAGE
+struct vm_area_struct;
+void copy_user_highpage(struct page *to, struct page *from,
+			unsigned long vaddr, struct vm_area_struct *vma);
+#define __HAVE_ARCH_COPY_HIGHPAGE
+void copy_highpage(struct page *to, struct page *from);
 
 /* Unlike sparc32, sparc64's parameter passing API is more
  * sane in that structures which as small enough are passed
diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h
index 339920f..44d6ac4 100644
--- a/arch/sparc/include/asm/pgtable_64.h
+++ b/arch/sparc/include/asm/pgtable_64.h
@@ -19,6 +19,7 @@
 #include <asm/types.h>
 #include <asm/spitfire.h>
 #include <asm/asi.h>
+#include <asm/adi.h>
 #include <asm/page.h>
 #include <asm/processor.h>
 
@@ -164,6 +165,8 @@ bool kern_addr_valid(unsigned long addr);
 #define _PAGE_E_4V	  _AC(0x0000000000000800,UL) /* side-Effect          */
 #define _PAGE_CP_4V	  _AC(0x0000000000000400,UL) /* Cacheable in P-Cache */
 #define _PAGE_CV_4V	  _AC(0x0000000000000200,UL) /* Cacheable in V-Cache */
+/* Bit 9 is used to enable MCD corruption detection instead on M7 */
+#define _PAGE_MCD_4V      _AC(0x0000000000000200,UL) /* Memory Corruption    */
 #define _PAGE_P_4V	  _AC(0x0000000000000100,UL) /* Privileged Page      */
 #define _PAGE_EXEC_4V	  _AC(0x0000000000000080,UL) /* Executable Page      */
 #define _PAGE_W_4V	  _AC(0x0000000000000040,UL) /* Writable             */
@@ -604,6 +607,18 @@ static inline pte_t pte_mkspecial(pte_t pte)
 	return pte;
 }
 
+static inline pte_t pte_mkmcd(pte_t pte)
+{
+	pte_val(pte) |= _PAGE_MCD_4V;
+	return pte;
+}
+
+static inline pte_t pte_mknotmcd(pte_t pte)
+{
+	pte_val(pte) &= ~_PAGE_MCD_4V;
+	return pte;
+}
+
 static inline unsigned long pte_young(pte_t pte)
 {
 	unsigned long mask;
@@ -1046,6 +1061,39 @@ int page_in_phys_avail(unsigned long paddr);
 int remap_pfn_range(struct vm_area_struct *, unsigned long, unsigned long,
 		    unsigned long, pgprot_t);
 
+void adi_restore_tags(struct mm_struct *mm, struct vm_area_struct *vma,
+		      unsigned long addr, pte_t pte);
+
+int adi_save_tags(struct mm_struct *mm, struct vm_area_struct *vma,
+		  unsigned long addr, pte_t oldpte);
+
+#define __HAVE_ARCH_DO_SWAP_PAGE
+static inline void arch_do_swap_page(struct mm_struct *mm,
+				     struct vm_area_struct *vma,
+				     unsigned long addr,
+				     pte_t pte, pte_t oldpte)
+{
+	/* If this is a new page being mapped in, there can be no
+	 * ADI tags stored away for this page. Skip looking for
+	 * stored tags
+	 */
+	if (pte_none(oldpte))
+		return;
+
+	if (adi_state.enabled && (pte_val(pte) & _PAGE_MCD_4V))
+		adi_restore_tags(mm, vma, addr, pte);
+}
+
+#define __HAVE_ARCH_UNMAP_ONE
+static inline int arch_unmap_one(struct mm_struct *mm,
+				 struct vm_area_struct *vma,
+				 unsigned long addr, pte_t oldpte)
+{
+	if (adi_state.enabled && (pte_val(oldpte) & _PAGE_MCD_4V))
+		return adi_save_tags(mm, vma, addr, oldpte);
+	return 0;
+}
+
 static inline int io_remap_pfn_range(struct vm_area_struct *vma,
 				     unsigned long from, unsigned long pfn,
 				     unsigned long size, pgprot_t prot)
diff --git a/arch/sparc/include/asm/thread_info_64.h b/arch/sparc/include/asm/thread_info_64.h
index f7e7b0b..7fb6763 100644
--- a/arch/sparc/include/asm/thread_info_64.h
+++ b/arch/sparc/include/asm/thread_info_64.h
@@ -188,7 +188,7 @@ register struct thread_info *current_thread_info_reg asm("g6");
  *       in using in assembly, else we can't use the mask as
  *       an immediate value in instructions such as andcc.
  */
-/* flag bit 12 is available */
+#define TIF_MCDPER		12	/* Precise MCD exception */
 #define TIF_MEMDIE		13	/* is terminating due to OOM killer */
 #define TIF_POLLING_NRFLAG	14
 
diff --git a/arch/sparc/include/asm/trap_block.h b/arch/sparc/include/asm/trap_block.h
index 6a4c865..0f6d0c4 100644
--- a/arch/sparc/include/asm/trap_block.h
+++ b/arch/sparc/include/asm/trap_block.h
@@ -76,6 +76,8 @@ extern struct sun4v_1insn_patch_entry __sun4v_1insn_patch,
 	__sun4v_1insn_patch_end;
 extern struct sun4v_1insn_patch_entry __fast_win_ctrl_1insn_patch,
 	__fast_win_ctrl_1insn_patch_end;
+extern struct sun4v_1insn_patch_entry __sun_m7_1insn_patch,
+	__sun_m7_1insn_patch_end;
 
 struct sun4v_2insn_patch_entry {
 	unsigned int	addr;
diff --git a/arch/sparc/include/asm/ttable.h b/arch/sparc/include/asm/ttable.h
index ede2b66..8f64694 100644
--- a/arch/sparc/include/asm/ttable.h
+++ b/arch/sparc/include/asm/ttable.h
@@ -219,6 +219,16 @@
 	nop;						\
 	nop;
 
+#define SUN4V_MCD_PRECISE				\
+	ldxa	[%g0] ASI_SCRATCHPAD, %g2;		\
+	ldx	[%g2 + HV_FAULT_D_ADDR_OFFSET], %g4;	\
+	ldx	[%g2 + HV_FAULT_D_CTX_OFFSET], %g5;	\
+	ba,pt	%xcc, etrap;				\
+	 rd	%pc, %g7;				\
+	ba,pt	%xcc, sun4v_mcd_detect_precise;		\
+	 nop;						\
+	nop;
+
 /* Before touching these macros, you owe it to yourself to go and
  * see how arch/sparc64/kernel/winfixup.S works... -DaveM
  *
diff --git a/arch/sparc/include/uapi/asm/asi.h b/arch/sparc/include/uapi/asm/asi.h
index d371b26..fbb30a5b 100644
--- a/arch/sparc/include/uapi/asm/asi.h
+++ b/arch/sparc/include/uapi/asm/asi.h
@@ -145,6 +145,8 @@
  * ASIs, "(4V)" designates SUN4V specific ASIs.  "(NG4)" designates SPARC-T4
  * and later ASIs.
  */
+#define ASI_MCD_PRIV_PRIMARY	0x02 /* (NG7) Privileged MCD version VA	*/
+#define ASI_MCD_REAL		0x05 /* (NG7) Privileged MCD version PA	*/
 #define ASI_PHYS_USE_EC		0x14 /* PADDR, E-cachable		*/
 #define ASI_PHYS_BYPASS_EC_E	0x15 /* PADDR, E-bit			*/
 #define ASI_BLK_AIUP_4V		0x16 /* (4V) Prim, user, block ld/st	*/
@@ -245,6 +247,9 @@
 #define ASI_UDBL_CONTROL_R	0x7f /* External UDB control regs rd low*/
 #define ASI_INTR_R		0x7f /* IRQ vector dispatch read	*/
 #define ASI_INTR_DATAN_R	0x7f /* (III) In irq vector data reg N	*/
+#define ASI_MCD_PRIMARY		0x90 /* (NG7) MCD version load/store	*/
+#define ASI_MCD_ST_BLKINIT_PRIMARY	\
+				0x92 /* (NG7) MCD store BLKINIT primary	*/
 #define ASI_PIC			0xb0 /* (NG4) PIC registers		*/
 #define ASI_PST8_P		0xc0 /* Primary, 8 8-bit, partial	*/
 #define ASI_PST8_S		0xc1 /* Secondary, 8 8-bit, partial	*/
diff --git a/arch/sparc/include/uapi/asm/auxvec.h b/arch/sparc/include/uapi/asm/auxvec.h
index 5f80a70..ab8780f 100644
--- a/arch/sparc/include/uapi/asm/auxvec.h
+++ b/arch/sparc/include/uapi/asm/auxvec.h
@@ -3,6 +3,13 @@
 
 #define AT_SYSINFO_EHDR		33
 
-#define AT_VECTOR_SIZE_ARCH	1
+/* Avoid overlap with other AT_* values since they are consolidated in
+ * glibc and any overlaps can cause problems
+ */
+#define AT_ADI_BLKSZ	48
+#define AT_ADI_NBITS	49
+#define AT_ADI_UEONADI	50
+
+#define AT_VECTOR_SIZE_ARCH	4
 
 #endif /* !(__ASMSPARC_AUXVEC_H) */
diff --git a/arch/sparc/include/uapi/asm/mman.h b/arch/sparc/include/uapi/asm/mman.h
index 715a2c9..f6f99ec 100644
--- a/arch/sparc/include/uapi/asm/mman.h
+++ b/arch/sparc/include/uapi/asm/mman.h
@@ -6,6 +6,8 @@
 
 /* SunOS'ified... */
 
+#define PROT_ADI	0x10		/* ADI enabled */
+
 #define MAP_RENAME      MAP_ANONYMOUS   /* In SunOS terminology */
 #define MAP_NORESERVE   0x40            /* don't reserve swap pages */
 #define MAP_INHERIT     0x80            /* SunOS doesn't do this, but... */
diff --git a/arch/sparc/include/uapi/asm/pstate.h b/arch/sparc/include/uapi/asm/pstate.h
index b6999c9..ceca96e 100644
--- a/arch/sparc/include/uapi/asm/pstate.h
+++ b/arch/sparc/include/uapi/asm/pstate.h
@@ -11,7 +11,12 @@
  * -----------------------------------------------------------------------
  *  63  12  11   10    9     8    7   6   5     4     3     2     1    0
  */
+/* IG on V9 conflicts with MCDE on M7. PSTATE_MCDE will only be used on
+ * processors that support ADI which do not use IG, hence there is no
+ * functional conflict
+ */
 #define PSTATE_IG   _AC(0x0000000000000800,UL) /* Interrupt Globals.	*/
+#define PSTATE_MCDE _AC(0x0000000000000800,UL) /* MCD Enable		*/
 #define PSTATE_MG   _AC(0x0000000000000400,UL) /* MMU Globals.		*/
 #define PSTATE_CLE  _AC(0x0000000000000200,UL) /* Current Little Endian.*/
 #define PSTATE_TLE  _AC(0x0000000000000100,UL) /* Trap Little Endian.	*/
@@ -48,7 +53,12 @@
 #define TSTATE_ASI	_AC(0x00000000ff000000,UL) /* AddrSpace ID.	*/
 #define TSTATE_PIL	_AC(0x0000000000f00000,UL) /* %pil (Linux traps)*/
 #define TSTATE_PSTATE	_AC(0x00000000000fff00,UL) /* PSTATE.		*/
+/* IG on V9 conflicts with MCDE on M7. TSTATE_MCDE will only be used on
+ * processors that support ADI which do not support IG, hence there is
+ * no functional conflict
+ */
 #define TSTATE_IG	_AC(0x0000000000080000,UL) /* Interrupt Globals.*/
+#define TSTATE_MCDE	_AC(0x0000000000080000,UL) /* MCD enable.       */
 #define TSTATE_MG	_AC(0x0000000000040000,UL) /* MMU Globals.	*/
 #define TSTATE_CLE	_AC(0x0000000000020000,UL) /* CurrLittleEndian.	*/
 #define TSTATE_TLE	_AC(0x0000000000010000,UL) /* TrapLittleEndian.	*/