Merge branch 'akpm' (patches from Andrew)

Merge yet more updates from Andrew Morton:

 - More MM work. 100ish more to go. Mike Rapoport's "mm: remove
   __ARCH_HAS_5LEVEL_HACK" series should fix the current ppc issue

 - Various other little subsystems

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (127 commits)
  lib/ubsan.c: fix gcc-10 warnings
  tools/testing/selftests/vm: remove duplicate headers
  selftests: vm: pkeys: fix multilib builds for x86
  selftests: vm: pkeys: use the correct page size on powerpc
  selftests/vm/pkeys: override access right definitions on powerpc
  selftests/vm/pkeys: test correct behaviour of pkey-0
  selftests/vm/pkeys: introduce a sub-page allocator
  selftests/vm/pkeys: detect write violation on a mapped access-denied-key page
  selftests/vm/pkeys: associate key on a mapped page and detect write violation
  selftests/vm/pkeys: associate key on a mapped page and detect access violation
  selftests/vm/pkeys: improve checks to determine pkey support
  selftests/vm/pkeys: fix assertion in test_pkey_alloc_exhaust()
  selftests/vm/pkeys: fix number of reserved powerpc pkeys
  selftests/vm/pkeys: introduce powerpc support
  selftests/vm/pkeys: introduce generic pkey abstractions
  selftests: vm: pkeys: use the correct huge page size
  selftests/vm/pkeys: fix alloc_random_pkey() to make it really random
  selftests/vm/pkeys: fix assertion in pkey_disable_set/clear()
  selftests/vm/pkeys: fix pkey_disable_clear()
  selftests: vm: pkeys: add helpers for pkey bits
  ...

Documentation/dev-tools/kcov.rst

@@ -217,14 +217,15 @@ This allows to collect coverage from two types of kernel background
 threads: the global ones, that are spawned during kernel boot in a limited
 number of instances (e.g. one USB hub_event() worker thread is spawned per
 USB HCD); and the local ones, that are spawned when a user interacts with
-some kernel interface (e.g. vhost workers).
+some kernel interface (e.g. vhost workers); as well as from soft
+interrupts.
 
-To enable collecting coverage from a global background thread, a unique
-global handle must be assigned and passed to the corresponding
-kcov_remote_start() call. Then a userspace process can pass a list of such
-handles to the KCOV_REMOTE_ENABLE ioctl in the handles array field of the
-kcov_remote_arg struct. This will attach the used kcov device to the code
-sections, that are referenced by those handles.
+To enable collecting coverage from a global background thread or from a
+softirq, a unique global handle must be assigned and passed to the
+corresponding kcov_remote_start() call. Then a userspace process can pass
+a list of such handles to the KCOV_REMOTE_ENABLE ioctl in the handles
+array field of the kcov_remote_arg struct. This will attach the used kcov
+device to the code sections, that are referenced by those handles.
 
 Since there might be many local background threads spawned from different
 userspace processes, we can't use a single global handle per annotation.
@@ -242,7 +243,7 @@ handles as they don't belong to a particular subsystem. The bytes 4-7 are
 currently reserved and must be zero. In the future the number of bytes
 used for the subsystem or handle ids might be increased.
 
-When a particular userspace proccess collects coverage by via a common
+When a particular userspace proccess collects coverage via a common
 handle, kcov will collect coverage for each code section that is annotated
 to use the common handle obtained as kcov_handle from the current
 task_struct. However non common handles allow to collect coverage

Documentation/features/debug/debug-vm-pgtable/arch-support.txt

@@ -0,0 +1,34 @@
+#
+# Feature name:          debug-vm-pgtable
+#         Kconfig:       ARCH_HAS_DEBUG_VM_PGTABLE
+#         description:   arch supports pgtable tests for semantics compliance
+#
+    -----------------------
+    |         arch |status|
+    -----------------------
+    |       alpha: | TODO |
+    |         arc: |  ok  |
+    |         arm: | TODO |
+    |       arm64: |  ok  |
+    |         c6x: | TODO |
+    |        csky: | TODO |
+    |       h8300: | TODO |
+    |     hexagon: | TODO |
+    |        ia64: | TODO |
+    |        m68k: | TODO |
+    |  microblaze: | TODO |
+    |        mips: | TODO |
+    |       nds32: | TODO |
+    |       nios2: | TODO |
+    |    openrisc: | TODO |
+    |      parisc: | TODO |
+    |     powerpc: |  ok  |
+    |       riscv: | TODO |
+    |        s390: |  ok  |
+    |          sh: | TODO |
+    |       sparc: | TODO |
+    |          um: | TODO |
+    |   unicore32: | TODO |
+    |         x86: |  ok  |
+    |      xtensa: | TODO |
+    -----------------------

arch/arc/Kconfig

@@ -6,6 +6,7 @@
 config ARC
 	def_bool y
 	select ARC_TIMERS
+	select ARCH_HAS_DEBUG_VM_PGTABLE
 	select ARCH_HAS_DMA_PREP_COHERENT
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_HAS_SETUP_DMA_OPS

arch/arc/include/asm/highmem.h

@@ -25,33 +25,15 @@
 #define PKMAP_ADDR(nr)		(PKMAP_BASE + ((nr) << PAGE_SHIFT))
 #define PKMAP_NR(virt)		(((virt) - PKMAP_BASE) >> PAGE_SHIFT)
 
-#define kmap_prot		PAGE_KERNEL
-
-
 #include <asm/cacheflush.h>
 
-extern void *kmap(struct page *page);
-extern void *kmap_high(struct page *page);
-extern void *kmap_atomic(struct page *page);
-extern void __kunmap_atomic(void *kvaddr);
-extern void kunmap_high(struct page *page);
-
 extern void kmap_init(void);
 
 static inline void flush_cache_kmaps(void)
 {
 	flush_cache_all();
 }
 
-static inline void kunmap(struct page *page)
-{
-	BUG_ON(in_interrupt());
-	if (!PageHighMem(page))
-		return;
-	kunmap_high(page);
-}
-
-
 #endif
 
 #endif

arch/arc/mm/highmem.c

@@ -49,38 +49,23 @@
 extern pte_t * pkmap_page_table;
 static pte_t * fixmap_page_table;
 
-void *kmap(struct page *page)
-{
-	BUG_ON(in_interrupt());
-	if (!PageHighMem(page))
-		return page_address(page);
-
-	return kmap_high(page);
-}
-EXPORT_SYMBOL(kmap);
-
-void *kmap_atomic(struct page *page)
+void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
 {
 	int idx, cpu_idx;
 	unsigned long vaddr;
 
-	preempt_disable();
-	pagefault_disable();
-	if (!PageHighMem(page))
-		return page_address(page);
-
 	cpu_idx = kmap_atomic_idx_push();
 	idx = cpu_idx + KM_TYPE_NR * smp_processor_id();
 	vaddr = FIXMAP_ADDR(idx);
 
 	set_pte_at(&init_mm, vaddr, fixmap_page_table + idx,
-		   mk_pte(page, kmap_prot));
+		   mk_pte(page, prot));
 
 	return (void *)vaddr;
 }
-EXPORT_SYMBOL(kmap_atomic);
+EXPORT_SYMBOL(kmap_atomic_high_prot);
 
-void __kunmap_atomic(void *kv)
+void kunmap_atomic_high(void *kv)
 {
 	unsigned long kvaddr = (unsigned long)kv;
 
@@ -102,11 +87,8 @@ void __kunmap_atomic(void *kv)
 
 		kmap_atomic_idx_pop();
 	}
-
-	pagefault_enable();
-	preempt_enable();
 }
-EXPORT_SYMBOL(__kunmap_atomic);
+EXPORT_SYMBOL(kunmap_atomic_high);
 
 static noinline pte_t * __init alloc_kmap_pgtable(unsigned long kvaddr)
 {

arch/arm/include/asm/highmem.h

@@ -10,8 +10,6 @@
 #define PKMAP_NR(virt)		(((virt) - PKMAP_BASE) >> PAGE_SHIFT)
 #define PKMAP_ADDR(nr)		(PKMAP_BASE + ((nr) << PAGE_SHIFT))
 
-#define kmap_prot		PAGE_KERNEL
-
 #define flush_cache_kmaps() \
 	do { \
 		if (cache_is_vivt()) \
@@ -20,9 +18,6 @@
 
 extern pte_t *pkmap_page_table;
 
-extern void *kmap_high(struct page *page);
-extern void kunmap_high(struct page *page);
-
 /*
  * The reason for kmap_high_get() is to ensure that the currently kmap'd
  * page usage count does not decrease to zero while we're using its
@@ -63,10 +58,6 @@ static inline void *kmap_high_get(struct page *page)
  * when CONFIG_HIGHMEM is not set.
  */
 #ifdef CONFIG_HIGHMEM
-extern void *kmap(struct page *page);
-extern void kunmap(struct page *page);
-extern void *kmap_atomic(struct page *page);
-extern void __kunmap_atomic(void *kvaddr);
 extern void *kmap_atomic_pfn(unsigned long pfn);
 #endif
 

arch/arm/include/asm/pgtable.h

@@ -17,7 +17,6 @@
 
 #else
 
-#define __ARCH_USE_5LEVEL_HACK
 #include <asm-generic/pgtable-nopud.h>
 #include <asm/memory.h>
 #include <asm/pgtable-hwdef.h>

arch/arm/lib/uaccess_with_memcpy.c

@@ -24,6 +24,7 @@ pin_page_for_write(const void __user *_addr, pte_t **ptep, spinlock_t **ptlp)
 {
 	unsigned long addr = (unsigned long)_addr;
 	pgd_t *pgd;
+	p4d_t *p4d;
 	pmd_t *pmd;
 	pte_t *pte;
 	pud_t *pud;
@@ -33,7 +34,11 @@ pin_page_for_write(const void __user *_addr, pte_t **ptep, spinlock_t **ptlp)
 	if (unlikely(pgd_none(*pgd) || pgd_bad(*pgd)))
 		return 0;
 
-	pud = pud_offset(pgd, addr);
+	p4d = p4d_offset(pgd, addr);
+	if (unlikely(p4d_none(*p4d) || p4d_bad(*p4d)))
+		return 0;
+
+	pud = pud_offset(p4d, addr);
 	if (unlikely(pud_none(*pud) || pud_bad(*pud)))
 		return 0;
 

arch/arm/mach-sa1100/assabet.c

@@ -633,7 +633,7 @@ static void __init map_sa1100_gpio_regs( void )
 	int prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_DOMAIN(DOMAIN_IO);
 	pmd_t *pmd;
 
-	pmd = pmd_offset(pud_offset(pgd_offset_k(virt), virt), virt);
+	pmd = pmd_offset(pud_offset(p4d_offset(pgd_offset_k(virt), virt), virt), virt);
 	*pmd = __pmd(phys | prot);
 	flush_pmd_entry(pmd);
 }

arch/arm/mm/dump.c

@@ -207,6 +207,7 @@ struct pg_level {
 static struct pg_level pg_level[] = {
 	{
 	}, { /* pgd */
+	}, { /* p4d */
 	}, { /* pud */
 	}, { /* pmd */
 		.bits	= section_bits,
@@ -308,7 +309,7 @@ static void walk_pte(struct pg_state *st, pmd_t *pmd, unsigned long start,
 
 	for (i = 0; i < PTRS_PER_PTE; i++, pte++) {
 		addr = start + i * PAGE_SIZE;
-		note_page(st, addr, 4, pte_val(*pte), domain);
+		note_page(st, addr, 5, pte_val(*pte), domain);
 	}
 }
 
@@ -350,14 +351,14 @@ static void walk_pmd(struct pg_state *st, pud_t *pud, unsigned long start)
 			addr += SECTION_SIZE;
 			pmd++;
 			domain = get_domain_name(pmd);
-			note_page(st, addr, 3, pmd_val(*pmd), domain);
+			note_page(st, addr, 4, pmd_val(*pmd), domain);
 		}
 	}
 }
 
-static void walk_pud(struct pg_state *st, pgd_t *pgd, unsigned long start)
+static void walk_pud(struct pg_state *st, p4d_t *p4d, unsigned long start)
 {
-	pud_t *pud = pud_offset(pgd, 0);
+	pud_t *pud = pud_offset(p4d, 0);
 	unsigned long addr;
 	unsigned i;
 
@@ -366,7 +367,23 @@ static void walk_pud(struct pg_state *st, pgd_t *pgd, unsigned long start)
 		if (!pud_none(*pud)) {
 			walk_pmd(st, pud, addr);
 		} else {
-			note_page(st, addr, 2, pud_val(*pud), NULL);
+			note_page(st, addr, 3, pud_val(*pud), NULL);
+		}
+	}
+}
+
+static void walk_p4d(struct pg_state *st, pgd_t *pgd, unsigned long start)
+{
+	p4d_t *p4d = p4d_offset(pgd, 0);
+	unsigned long addr;
+	unsigned i;
+
+	for (i = 0; i < PTRS_PER_P4D; i++, p4d++) {
+		addr = start + i * P4D_SIZE;
+		if (!p4d_none(*p4d)) {
+			walk_pud(st, p4d, addr);
+		} else {
+			note_page(st, addr, 2, p4d_val(*p4d), NULL);
 		}
 	}
 }
@@ -381,7 +398,7 @@ static void walk_pgd(struct pg_state *st, struct mm_struct *mm,
 	for (i = 0; i < PTRS_PER_PGD; i++, pgd++) {
 		addr = start + i * PGDIR_SIZE;
 		if (!pgd_none(*pgd)) {
-			walk_pud(st, pgd, addr);
+			walk_p4d(st, pgd, addr);
 		} else {
 			note_page(st, addr, 1, pgd_val(*pgd), NULL);
 		}

arch/arm/mm/fault-armv.c

@@ -91,6 +91,7 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address,
 {
 	spinlock_t *ptl;
 	pgd_t *pgd;
+	p4d_t *p4d;
 	pud_t *pud;
 	pmd_t *pmd;
 	pte_t *pte;
@@ -100,7 +101,11 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address,
 	if (pgd_none_or_clear_bad(pgd))
 		return 0;
 
-	pud = pud_offset(pgd, address);
+	p4d = p4d_offset(pgd, address);
+	if (p4d_none_or_clear_bad(p4d))
+		return 0;
+
+	pud = pud_offset(p4d, address);
 	if (pud_none_or_clear_bad(pud))
 		return 0;
 

arch/arm/mm/fault.c

@@ -43,19 +43,21 @@ void show_pte(const char *lvl, struct mm_struct *mm, unsigned long addr)
 	printk("%s[%08lx] *pgd=%08llx", lvl, addr, (long long)pgd_val(*pgd));
 
 	do {
+		p4d_t *p4d;
 		pud_t *pud;
 		pmd_t *pmd;
 		pte_t *pte;
 
-		if (pgd_none(*pgd))
+		p4d = p4d_offset(pgd, addr);
+		if (p4d_none(*p4d))
 			break;
 
-		if (pgd_bad(*pgd)) {
+		if (p4d_bad(*p4d)) {
 			pr_cont("(bad)");
 			break;
 		}
 
-		pud = pud_offset(pgd, addr);
+		pud = pud_offset(p4d, addr);
 		if (PTRS_PER_PUD != 1)
 			pr_cont(", *pud=%08llx", (long long)pud_val(*pud));
 
@@ -405,6 +407,7 @@ do_translation_fault(unsigned long addr, unsigned int fsr,
 {
 	unsigned int index;
 	pgd_t *pgd, *pgd_k;
+	p4d_t *p4d, *p4d_k;
 	pud_t *pud, *pud_k;
 	pmd_t *pmd, *pmd_k;
 
@@ -419,13 +422,16 @@ do_translation_fault(unsigned long addr, unsigned int fsr,
 	pgd = cpu_get_pgd() + index;
 	pgd_k = init_mm.pgd + index;
 
-	if (pgd_none(*pgd_k))
+	p4d = p4d_offset(pgd, addr);
+	p4d_k = p4d_offset(pgd_k, addr);
+
+	if (p4d_none(*p4d_k))
 		goto bad_area;
-	if (!pgd_present(*pgd))
-		set_pgd(pgd, *pgd_k);
+	if (!p4d_present(*p4d))
+		set_p4d(p4d, *p4d_k);
 
-	pud = pud_offset(pgd, addr);
-	pud_k = pud_offset(pgd_k, addr);
+	pud = pud_offset(p4d, addr);
+	pud_k = pud_offset(p4d_k, addr);
 
 	if (pud_none(*pud_k))
 		goto bad_area;