Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Martin Schwidefsky: - New entropy generation for the pseudo random number generator. - Early boot printk output via sclp to help debug crashes on boot. This needs to be enabled with a kernel parameter. - Add proper no-execute support with a bit in the page table entry. - Bug fixes and cleanups. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (65 commits) s390/syscall: fix single stepped system calls s390/zcrypt: make ap_bus explicitly non-modular s390/zcrypt: Removed unneeded debug feature directory creation. s390: add missing "do {} while (0)" loop constructs to multiline macros s390/mm: add cond_resched call to kernel page table dumper s390: get rid of MACHINE_HAS_PFMF and MACHINE_HAS_HPAGE s390/mm: make memory_block_size_bytes available for !MEMORY_HOTPLUG s390: replace ACCESS_ONCE with READ_ONCE s390: Audit and remove any remaining unnecessary uses of module.h s390: mm: Audit and remove any unnecessary uses of module.h s390: kernel: Audit and remove any unnecessary uses of module.h s390/kdump: Use "LINUX" ELF note name instead of "CORE" s390: add no-execute support s390: report new vector facilities s390: use correct input data address for setup_randomness s390/sclp: get rid of common response code handling s390/sclp: don't add new lines to each printed string s390/sclp: make early sclp code readable s390/sclp: disable early sclp code as soon as the base sclp driver is active s390/sclp: move early printk code to drivers ...
2017-02-22 10:20:04 -08:00
--- a/arch/s390/mm/cmm.c
+++ b/arch/s390/mm/cmm.c
@@ -10,6 +10,7 @@
 #include <linux/fs.h>
 #include <linux/init.h>
 #include <linux/module.h>
+#include <linux/moduleparam.h>
 #include <linux/gfp.h>
 #include <linux/sched.h>
 #include <linux/sysctl.h>
--- a/arch/s390/mm/dump_pagetables.c
+++ b/arch/s390/mm/dump_pagetables.c
@@ -1,6 +1,6 @@
 #include <linux/seq_file.h>
 #include <linux/debugfs.h>
-#include <linux/module.h>
+#include <linux/sched.h>
 #include <linux/mm.h>
 #include <asm/sections.h>
 #include <asm/pgtable.h>
@@ -49,8 +49,8 @@ static void print_prot(struct seq_file *m, unsigned int pr, int level)
 		seq_printf(m, "I\n");
 		return;
 	}
-	seq_printf(m, "%s", pr & _PAGE_PROTECT ? "RO " : "RW ");
-	seq_putc(m, '\n');
+	seq_puts(m, (pr & _PAGE_PROTECT) ? "RO " : "RW ");
+	seq_puts(m, (pr & _PAGE_NOEXEC) ? "NX\n" : "X\n");
 }

 static void note_page(struct seq_file *m, struct pg_state *st,
@@ -117,7 +117,8 @@ static void walk_pte_level(struct seq_file *m, struct pg_state *st,
 	for (i = 0; i < PTRS_PER_PTE && addr < max_addr; i++) {
 		st->current_address = addr;
 		pte = pte_offset_kernel(pmd, addr);
-		prot = pte_val(*pte) & (_PAGE_PROTECT | _PAGE_INVALID);
+		prot = pte_val(*pte) &
+			(_PAGE_PROTECT | _PAGE_INVALID | _PAGE_NOEXEC);
 		note_page(m, st, prot, 4);
 		addr += PAGE_SIZE;
 	}
@@ -135,7 +136,9 @@ static void walk_pmd_level(struct seq_file *m, struct pg_state *st,
 		pmd = pmd_offset(pud, addr);
 		if (!pmd_none(*pmd)) {
 			if (pmd_large(*pmd)) {
-				prot = pmd_val(*pmd) & _SEGMENT_ENTRY_PROTECT;
+				prot = pmd_val(*pmd) &
+					(_SEGMENT_ENTRY_PROTECT |
+					 _SEGMENT_ENTRY_NOEXEC);
 				note_page(m, st, prot, 3);
 			} else
 				walk_pte_level(m, st, pmd, addr);
@@ -157,7 +160,9 @@ static void walk_pud_level(struct seq_file *m, struct pg_state *st,
 		pud = pud_offset(pgd, addr);
 		if (!pud_none(*pud))
 			if (pud_large(*pud)) {
-				prot = pud_val(*pud) & _REGION_ENTRY_PROTECT;
+				prot = pud_val(*pud) &
+					(_REGION_ENTRY_PROTECT |
+					 _REGION_ENTRY_NOEXEC);
 				note_page(m, st, prot, 2);
 			} else
 				walk_pmd_level(m, st, pud, addr);
@@ -183,6 +188,7 @@ static void walk_pgd_level(struct seq_file *m)
 		else
 			note_page(m, &st, _PAGE_INVALID, 1);
 		addr += PGDIR_SIZE;
+		cond_resched();
 	}
 	/* Flush out the last page */
 	st.current_address = max_addr;
--- a/arch/s390/mm/extmem.c
+++ b/arch/s390/mm/extmem.c
@@ -14,7 +14,7 @@
 #include <linux/spinlock.h>
 #include <linux/list.h>
 #include <linux/slab.h>
-#include <linux/module.h>
+#include <linux/export.h>
 #include <linux/bootmem.h>
 #include <linux/ctype.h>
 #include <linux/ioport.h>
@@ -154,7 +154,7 @@ dcss_mkname(char *name, char *dcss_name)
 		if (name[i] == '\0')
 			break;
 		dcss_name[i] = toupper(name[i]);
-	};
+	}
 	for (; i < 8; i++)
 		dcss_name[i] = ' ';
 	ASCEBC(dcss_name, 8);
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -311,12 +311,34 @@ static noinline void do_sigbus(struct pt_regs *regs)
 	force_sig_info(SIGBUS, &si, tsk);
 }

-static noinline void do_fault_error(struct pt_regs *regs, int fault)
+static noinline int signal_return(struct pt_regs *regs)
+{
+	u16 instruction;
+	int rc;
+
+	rc = __get_user(instruction, (u16 __user *) regs->psw.addr);
+	if (rc)
+		return rc;
+	if (instruction == 0x0a77) {
+		set_pt_regs_flag(regs, PIF_SYSCALL);
+		regs->int_code = 0x00040077;
+		return 0;
+	} else if (instruction == 0x0aad) {
+		set_pt_regs_flag(regs, PIF_SYSCALL);
+		regs->int_code = 0x000400ad;
+		return 0;
+	}
+	return -EACCES;
+}
+
+static noinline void do_fault_error(struct pt_regs *regs, int access, int fault)
 {
 	int si_code;

 	switch (fault) {
 	case VM_FAULT_BADACCESS:
+		if (access == VM_EXEC && signal_return(regs) == 0)
+			break;
 	case VM_FAULT_BADMAP:
 		/* Bad memory access. Check if it is kernel or user space. */
 		if (user_mode(regs)) {
@@ -324,7 +346,7 @@ static noinline void do_fault_error(struct pt_regs *regs, int fault)
 			si_code = (fault == VM_FAULT_BADMAP) ?
 				SEGV_MAPERR : SEGV_ACCERR;
 			do_sigsegv(regs, si_code);
-			return;
+			break;
 		}
 	case VM_FAULT_BADCONTEXT:
 	case VM_FAULT_PFAULT:
@@ -525,7 +547,7 @@ out:
 void do_protection_exception(struct pt_regs *regs)
 {
 	unsigned long trans_exc_code;
-	int fault;
+	int access, fault;

 	trans_exc_code = regs->int_parm_long;
 	/*
@@ -544,9 +566,17 @@ void do_protection_exception(struct pt_regs *regs)
 		do_low_address(regs);
 		return;
 	}
-	fault = do_exception(regs, VM_WRITE);
+	if (unlikely(MACHINE_HAS_NX && (trans_exc_code & 0x80))) {
+		regs->int_parm_long = (trans_exc_code & ~PAGE_MASK) |
+					(regs->psw.addr & PAGE_MASK);
+		access = VM_EXEC;
+		fault = VM_FAULT_BADACCESS;
+	} else {
+		access = VM_WRITE;
+		fault = do_exception(regs, access);
+	}
 	if (unlikely(fault))
-		do_fault_error(regs, fault);
+		do_fault_error(regs, access, fault);
 }
 NOKPROBE_SYMBOL(do_protection_exception);

@@ -557,7 +587,7 @@ void do_dat_exception(struct pt_regs *regs)
 	access = VM_READ | VM_EXEC | VM_WRITE;
 	fault = do_exception(regs, access);
 	if (unlikely(fault))
-		do_fault_error(regs, fault);
+		do_fault_error(regs, access, fault);
 }
 NOKPROBE_SYMBOL(do_dat_exception);

--- a/arch/s390/mm/hugetlbpage.c
+++ b/arch/s390/mm/hugetlbpage.c
@@ -59,6 +59,8 @@ static inline unsigned long __pte_to_rste(pte_t pte)
 		rste |= move_set_bit(pte_val(pte), _PAGE_SOFT_DIRTY,
 				     _SEGMENT_ENTRY_SOFT_DIRTY);
 #endif
+		rste |= move_set_bit(pte_val(pte), _PAGE_NOEXEC,
+				     _SEGMENT_ENTRY_NOEXEC);
 	} else
 		rste = _SEGMENT_ENTRY_INVALID;
 	return rste;
@@ -113,6 +115,8 @@ static inline pte_t __rste_to_pte(unsigned long rste)
 		pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_SOFT_DIRTY,
 					     _PAGE_DIRTY);
 #endif
+		pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_NOEXEC,
+					     _PAGE_NOEXEC);
 	} else
 		pte_val(pte) = _PAGE_INVALID;
 	return pte;
@@ -121,7 +125,11 @@ static inline pte_t __rste_to_pte(unsigned long rste)
 void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 		     pte_t *ptep, pte_t pte)
 {
-	unsigned long rste = __pte_to_rste(pte);
+	unsigned long rste;
+
+	rste = __pte_to_rste(pte);
+	if (!MACHINE_HAS_NX)
+		rste &= ~_SEGMENT_ENTRY_NOEXEC;

 	/* Set correct table type for 2G hugepages */
 	if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -137,6 +137,9 @@ void __init mem_init(void)

 void free_initmem(void)
 {
+	__set_memory((unsigned long) _sinittext,
+		     (_einittext - _sinittext) >> PAGE_SHIFT,
+		     SET_MEMORY_RW | SET_MEMORY_NX);
 	free_initmem_default(POISON_FREE_INITMEM);
 }

@@ -148,6 +151,15 @@ void __init free_initrd_mem(unsigned long start, unsigned long end)
 }
 #endif

+unsigned long memory_block_size_bytes(void)
+{
+	/*
+	 * Make sure the memory block size is always greater
+	 * or equal than the memory increment size.
+	 */
+	return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp.rzm);
+}
+
 #ifdef CONFIG_MEMORY_HOTPLUG
 int arch_add_memory(int nid, u64 start, u64 size, bool for_device)
 {
@@ -191,15 +203,6 @@ int arch_add_memory(int nid, u64 start, u64 size, bool for_device)
 	return rc;
 }

-unsigned long memory_block_size_bytes(void)
-{
-	/*
-	 * Make sure the memory block size is always greater
-	 * or equal than the memory increment size.
-	 */
-	return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp.rzm);
-}
-
 #ifdef CONFIG_MEMORY_HOTREMOVE
 int arch_remove_memory(u64 start, u64 size)
 {
--- a/arch/s390/mm/mem_detect.c
+++ b/arch/s390/mm/mem_detect.c
@@ -5,7 +5,6 @@
 */

 #include <linux/kernel.h>
-#include <linux/module.h>
 #include <linux/memblock.h>
 #include <linux/init.h>
 #include <linux/debugfs.h>
@@ -19,6 +18,8 @@

 static inline void memblock_physmem_add(phys_addr_t start, phys_addr_t size)
 {
+	memblock_dbg("memblock_physmem_add: [%#016llx-%#016llx]\n",
+		     start, start + size - 1);
 	memblock_add_range(&memblock.memory, start, size, 0, 0);
 	memblock_add_range(&memblock.physmem, start, size, 0, 0);
 }
@@ -39,7 +40,8 @@ void __init detect_memory_memblock(void)
 	memblock_set_bottom_up(true);
 	do {
 		size = 0;
-		type = tprot(addr);
+		/* assume lowcore is writable */
+		type = addr ? tprot(addr) : CHUNK_READ_WRITE;
 		do {
 			size += rzm;
 			if (max_physmem_end && addr + size >= max_physmem_end)
@@ -55,4 +57,5 @@ void __init detect_memory_memblock(void)
 	memblock_set_bottom_up(false);
 	if (!max_physmem_end)
 		max_physmem_end = memblock_end_of_DRAM();
+	memblock_dump_all();
 }
--- a/arch/s390/mm/mmap.c
+++ b/arch/s390/mm/mmap.c
@@ -26,11 +26,11 @@
 #include <linux/personality.h>
 #include <linux/mm.h>
 #include <linux/mman.h>
-#include <linux/module.h>
 #include <linux/random.h>
 #include <linux/compat.h>
 #include <linux/security.h>
 #include <asm/pgalloc.h>
+#include <asm/elf.h>

 static unsigned long stack_maxrandom_size(void)
 {
--- a/arch/s390/mm/pageattr.c
+++ b/arch/s390/mm/pageattr.c
@@ -3,7 +3,6 @@
 * Author(s): Jan Glauber <jang@linux.vnet.ibm.com>
 */
 #include <linux/hugetlb.h>
-#include <linux/module.h>
 #include <linux/mm.h>
 #include <asm/cacheflush.h>
 #include <asm/facility.h>
@@ -81,24 +80,24 @@ static void pgt_set(unsigned long *old, unsigned long new, unsigned long addr,
 	}
 }

-struct cpa {
-	unsigned int set_ro	: 1;
-	unsigned int clear_ro	: 1;
-};
-
 static int walk_pte_level(pmd_t *pmdp, unsigned long addr, unsigned long end,
-			  struct cpa cpa)
+			  unsigned long flags)
 {
 	pte_t *ptep, new;

 	ptep = pte_offset(pmdp, addr);
 	do {
-		if (pte_none(*ptep))
+		new = *ptep;
+		if (pte_none(new))
 			return -EINVAL;
-		if (cpa.set_ro)
-			new = pte_wrprotect(*ptep);
-		else if (cpa.clear_ro)
-			new = pte_mkwrite(pte_mkdirty(*ptep));
+		if (flags & SET_MEMORY_RO)
+			new = pte_wrprotect(new);
+		else if (flags & SET_MEMORY_RW)
+			new = pte_mkwrite(pte_mkdirty(new));
+		if ((flags & SET_MEMORY_NX) && MACHINE_HAS_NX)
+			pte_val(new) |= _PAGE_NOEXEC;
+		else if (flags & SET_MEMORY_X)
+			pte_val(new) &= ~_PAGE_NOEXEC;
 		pgt_set((unsigned long *)ptep, pte_val(new), addr, CRDTE_DTT_PAGE);
 		ptep++;
 		addr += PAGE_SIZE;
@@ -112,14 +111,17 @@ static int split_pmd_page(pmd_t *pmdp, unsigned long addr)
 	unsigned long pte_addr, prot;
 	pte_t *pt_dir, *ptep;
 	pmd_t new;
-	int i, ro;
+	int i, ro, nx;

 	pt_dir = vmem_pte_alloc();
 	if (!pt_dir)
 		return -ENOMEM;
 	pte_addr = pmd_pfn(*pmdp) << PAGE_SHIFT;
 	ro = !!(pmd_val(*pmdp) & _SEGMENT_ENTRY_PROTECT);
+	nx = !!(pmd_val(*pmdp) & _SEGMENT_ENTRY_NOEXEC);
 	prot = pgprot_val(ro ? PAGE_KERNEL_RO : PAGE_KERNEL);
+	if (!nx)
+		prot &= ~_PAGE_NOEXEC;
 	ptep = pt_dir;
 	for (i = 0; i < PTRS_PER_PTE; i++) {
 		pte_val(*ptep) = pte_addr | prot;
@@ -133,19 +135,24 @@ static int split_pmd_page(pmd_t *pmdp, unsigned long addr)
 	return 0;
 }

-static void modify_pmd_page(pmd_t *pmdp, unsigned long addr, struct cpa cpa)
+static void modify_pmd_page(pmd_t *pmdp, unsigned long addr,
+			    unsigned long flags)
 {
-	pmd_t new;
+	pmd_t new = *pmdp;

-	if (cpa.set_ro)
-		new = pmd_wrprotect(*pmdp);
-	else if (cpa.clear_ro)
-		new = pmd_mkwrite(pmd_mkdirty(*pmdp));
+	if (flags & SET_MEMORY_RO)
+		new = pmd_wrprotect(new);
+	else if (flags & SET_MEMORY_RW)
+		new = pmd_mkwrite(pmd_mkdirty(new));
+	if ((flags & SET_MEMORY_NX) && MACHINE_HAS_NX)
+		pmd_val(new) |= _SEGMENT_ENTRY_NOEXEC;
+	else if (flags & SET_MEMORY_X)
+		pmd_val(new) &= ~_SEGMENT_ENTRY_NOEXEC;
 	pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT);
 }

 static int walk_pmd_level(pud_t *pudp, unsigned long addr, unsigned long end,
-			  struct cpa cpa)
+			  unsigned long flags)
 {
 	unsigned long next;
 	pmd_t *pmdp;
@@ -163,9 +170,9 @@ static int walk_pmd_level(pud_t *pudp, unsigned long addr, unsigned long end,
 					return rc;
 				continue;
 			}
-			modify_pmd_page(pmdp, addr, cpa);
+			modify_pmd_page(pmdp, addr, flags);
 		} else {
-			rc = walk_pte_level(pmdp, addr, next, cpa);
+			rc = walk_pte_level(pmdp, addr, next, flags);
 			if (rc)
 				return rc;
 		}
@@ -181,14 +188,17 @@ static int split_pud_page(pud_t *pudp, unsigned long addr)
 	unsigned long pmd_addr, prot;
 	pmd_t *pm_dir, *pmdp;
 	pud_t new;
-	int i, ro;
+	int i, ro, nx;

 	pm_dir = vmem_pmd_alloc();
 	if (!pm_dir)
 		return -ENOMEM;
 	pmd_addr = pud_pfn(*pudp) << PAGE_SHIFT;
 	ro = !!(pud_val(*pudp) & _REGION_ENTRY_PROTECT);
+	nx = !!(pud_val(*pudp) & _REGION_ENTRY_NOEXEC);
 	prot = pgprot_val(ro ? SEGMENT_KERNEL_RO : SEGMENT_KERNEL);
+	if (!nx)
+		prot &= ~_SEGMENT_ENTRY_NOEXEC;
 	pmdp = pm_dir;
 	for (i = 0; i < PTRS_PER_PMD; i++) {
 		pmd_val(*pmdp) = pmd_addr | prot;
@@ -202,19 +212,24 @@ static int split_pud_page(pud_t *pudp, unsigned long addr)
 	return 0;
 }

-static void modify_pud_page(pud_t *pudp, unsigned long addr, struct cpa cpa)
+static void modify_pud_page(pud_t *pudp, unsigned long addr,
+			    unsigned long flags)
 {
-	pud_t new;
+	pud_t new = *pudp;

-	if (cpa.set_ro)
-		new = pud_wrprotect(*pudp);
-	else if (cpa.clear_ro)
-		new = pud_mkwrite(pud_mkdirty(*pudp));
+	if (flags & SET_MEMORY_RO)
+		new = pud_wrprotect(new);
+	else if (flags & SET_MEMORY_RW)
+		new = pud_mkwrite(pud_mkdirty(new));
+	if ((flags & SET_MEMORY_NX) && MACHINE_HAS_NX)
+		pud_val(new) |= _REGION_ENTRY_NOEXEC;
+	else if (flags & SET_MEMORY_X)
+		pud_val(new) &= ~_REGION_ENTRY_NOEXEC;
 	pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3);
 }

 static int walk_pud_level(pgd_t *pgd, unsigned long addr, unsigned long end,
-			  struct cpa cpa)
+			  unsigned long flags)
 {
 	unsigned long next;
 	pud_t *pudp;
@@ -232,9 +247,9 @@ static int walk_pud_level(pgd_t *pgd, unsigned long addr, unsigned long end,
 					break;
 				continue;
 			}
-			modify_pud_page(pudp, addr, cpa);
+			modify_pud_page(pudp, addr, flags);
 		} else {
-			rc = walk_pmd_level(pudp, addr, next, cpa);
+			rc = walk_pmd_level(pudp, addr, next, flags);
 		}
 		pudp++;
 		addr = next;
@@ -246,7 +261,7 @@ static int walk_pud_level(pgd_t *pgd, unsigned long addr, unsigned long end,
 static DEFINE_MUTEX(cpa_mutex);

 static int change_page_attr(unsigned long addr, unsigned long end,
-			    struct cpa cpa)
+			    unsigned long flags)
 {
 	unsigned long next;
 	int rc = -EINVAL;
@@ -262,7 +277,7 @@ static int change_page_attr(unsigned long addr, unsigned long end,
 		if (pgd_none(*pgdp))
 			break;
 		next = pgd_addr_end(addr, end);
-		rc = walk_pud_level(pgdp, addr, next, cpa);
+		rc = walk_pud_level(pgdp, addr, next, flags);
 		if (rc)
 			break;
 		cond_resched();
@@ -271,35 +286,10 @@ static int change_page_attr(unsigned long addr, unsigned long end,
 	return rc;
 }

-int set_memory_ro(unsigned long addr, int numpages)
+int __set_memory(unsigned long addr, int numpages, unsigned long flags)
 {
-	struct cpa cpa = {
-		.set_ro = 1,
-	};
-
 	addr &= PAGE_MASK;
-	return change_page_attr(addr, addr + numpages * PAGE_SIZE, cpa);
-}
-
-int set_memory_rw(unsigned long addr, int numpages)
-{
-	struct cpa cpa = {
-		.clear_ro = 1,
-	};
-
-	addr &= PAGE_MASK;
-	return change_page_attr(addr, addr + numpages * PAGE_SIZE, cpa);
-}
-
-/* not possible */
-int set_memory_nx(unsigned long addr, int numpages)
-{
-	return 0;
-}
-
-int set_memory_x(unsigned long addr, int numpages)
-{
-	return 0;
+	return change_page_attr(addr, addr + numpages * PAGE_SIZE, flags);
 }

 #ifdef CONFIG_DEBUG_PAGEALLOC
@@ -339,7 +329,7 @@ void __kernel_map_pages(struct page *page, int numpages, int enable)
 		nr = min(numpages - i, nr);
 		if (enable) {
 			for (j = 0; j < nr; j++) {
-				pte_val(*pte) = address | pgprot_val(PAGE_KERNEL);
+				pte_val(*pte) &= ~_PAGE_INVALID;
 				address += PAGE_SIZE;
 				pte++;
 			}
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -275,6 +275,8 @@ void ptep_modify_prot_commit(struct mm_struct *mm, unsigned long addr,
 {
 	pgste_t pgste;

+	if (!MACHINE_HAS_NX)
+		pte_val(pte) &= ~_PAGE_NOEXEC;
 	if (mm_has_pgste(mm)) {
 		pgste = pgste_get(ptep);
 		pgste_set_key(ptep, pgste, pte, mm);
--- a/arch/s390/mm/vmem.c
+++ b/arch/s390/mm/vmem.c
@@ -6,7 +6,7 @@
 #include <linux/bootmem.h>
 #include <linux/pfn.h>
 #include <linux/mm.h>
-#include <linux/module.h>
+#include <linux/init.h>
 #include <linux/list.h>
 #include <linux/hugetlb.h>
 #include <linux/slab.h>
@@ -79,6 +79,7 @@ pte_t __ref *vmem_pte_alloc(void)
 */
 static int vmem_add_mem(unsigned long start, unsigned long size)
 {
+	unsigned long pgt_prot, sgt_prot, r3_prot;
 	unsigned long pages4k, pages1m, pages2g;
 	unsigned long end = start + size;
 	unsigned long address = start;
@@ -88,6 +89,14 @@ static int vmem_add_mem(unsigned long start, unsigned long size)
 	pte_t *pt_dir;
 	int ret = -ENOMEM;

+	pgt_prot = pgprot_val(PAGE_KERNEL);
+	sgt_prot = pgprot_val(SEGMENT_KERNEL);
+	r3_prot = pgprot_val(REGION3_KERNEL);
+	if (!MACHINE_HAS_NX) {
+		pgt_prot &= ~_PAGE_NOEXEC;
+		sgt_prot &= ~_SEGMENT_ENTRY_NOEXEC;
+		r3_prot &= ~_REGION_ENTRY_NOEXEC;
+	}
 	pages4k = pages1m = pages2g = 0;
 	while (address < end) {
 		pg_dir = pgd_offset_k(address);
@@ -101,7 +110,7 @@ static int vmem_add_mem(unsigned long start, unsigned long size)
 		if (MACHINE_HAS_EDAT2 && pud_none(*pu_dir) && address &&
 		    !(address & ~PUD_MASK) && (address + PUD_SIZE <= end) &&
 		     !debug_pagealloc_enabled()) {
-			pud_val(*pu_dir) = address | pgprot_val(REGION3_KERNEL);
+			pud_val(*pu_dir) = address | r3_prot;
 			address += PUD_SIZE;
 			pages2g++;
 			continue;
@@ -116,7 +125,7 @@ static int vmem_add_mem(unsigned long start, unsigned long size)
 		if (MACHINE_HAS_EDAT1 && pmd_none(*pm_dir) && address &&
 		    !(address & ~PMD_MASK) && (address + PMD_SIZE <= end) &&
 		    !debug_pagealloc_enabled()) {
-			pmd_val(*pm_dir) = address | pgprot_val(SEGMENT_KERNEL);
+			pmd_val(*pm_dir) = address | sgt_prot;
 			address += PMD_SIZE;
 			pages1m++;
 			continue;
@@ -129,7 +138,7 @@ static int vmem_add_mem(unsigned long start, unsigned long size)
 		}

 		pt_dir = pte_offset_kernel(pm_dir, address);
-		pte_val(*pt_dir) = address |  pgprot_val(PAGE_KERNEL);
+		pte_val(*pt_dir) = address | pgt_prot;
 		address += PAGE_SIZE;
 		pages4k++;
 	}
@@ -200,6 +209,7 @@ static void vmem_remove_range(unsigned long start, unsigned long size)
 */
 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
 {
+	unsigned long pgt_prot, sgt_prot;
 	unsigned long address = start;
 	pgd_t *pg_dir;
 	pud_t *pu_dir;
@@ -207,6 +217,12 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
 	pte_t *pt_dir;
 	int ret = -ENOMEM;

+	pgt_prot = pgprot_val(PAGE_KERNEL);
+	sgt_prot = pgprot_val(SEGMENT_KERNEL);
+	if (!MACHINE_HAS_NX) {
+		pgt_prot &= ~_PAGE_NOEXEC;
+		sgt_prot &= ~_SEGMENT_ENTRY_NOEXEC;
+	}
 	for (address = start; address < end;) {
 		pg_dir = pgd_offset_k(address);
 		if (pgd_none(*pg_dir)) {
@@ -238,8 +254,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
 				new_page = vmemmap_alloc_block(PMD_SIZE, node);
 				if (!new_page)
 					goto out;
-				pmd_val(*pm_dir) = __pa(new_page) |
-					_SEGMENT_ENTRY | _SEGMENT_ENTRY_LARGE;
+				pmd_val(*pm_dir) = __pa(new_page) | sgt_prot;
 				address = (address + PMD_SIZE) & PMD_MASK;
 				continue;
 			}
@@ -259,8 +274,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
 			new_page = vmemmap_alloc_block(PAGE_SIZE, node);
 			if (!new_page)
 				goto out;
-			pte_val(*pt_dir) =
-				__pa(new_page) | pgprot_val(PAGE_KERNEL);
+			pte_val(*pt_dir) = __pa(new_page) | pgt_prot;
 		}
 		address += PAGE_SIZE;
 	}
@@ -372,13 +386,21 @@ out:
 */
 void __init vmem_map_init(void)
 {
-	unsigned long size = _eshared - _stext;
 	struct memblock_region *reg;

 	for_each_memblock(memory, reg)
 		vmem_add_mem(reg->base, reg->size);
-	set_memory_ro((unsigned long)_stext, size >> PAGE_SHIFT);
-	pr_info("Write protected kernel read-only data: %luk\n", size >> 10);
+	__set_memory((unsigned long) _stext,
+		     (_etext - _stext) >> PAGE_SHIFT,
+		     SET_MEMORY_RO | SET_MEMORY_X);
+	__set_memory((unsigned long) _etext,
+		     (_eshared - _etext) >> PAGE_SHIFT,
+		     SET_MEMORY_RO);
+	__set_memory((unsigned long) _sinittext,
+		     (_einittext - _sinittext) >> PAGE_SHIFT,
+		     SET_MEMORY_RO | SET_MEMORY_X);
+	pr_info("Write protected kernel read-only data: %luk\n",
+		(_eshared - _stext) >> 10);
 }

 /*