Merge branch 'akpm' (patches from Andrew)

Merge updates from Andrew Morton:
 "A few little subsystems and a start of a lot of MM patches.

  Subsystems affected by this patch series: squashfs, ocfs2, parisc,
  vfs. With mm subsystems: slab-generic, slub, debug, pagecache, gup,
  swap, memcg, pagemap, memory-failure, vmalloc, kasan"

* emailed patches from Andrew Morton <[email protected]>: (128 commits)
  kasan: move kasan_report() into report.c
  mm/mm_init.c: report kasan-tag information stored in page->flags
  ubsan: entirely disable alignment checks under UBSAN_TRAP
  kasan: fix clang compilation warning due to stack protector
  x86/mm: remove vmalloc faulting
  mm: remove vmalloc_sync_(un)mappings()
  x86/mm/32: implement arch_sync_kernel_mappings()
  x86/mm/64: implement arch_sync_kernel_mappings()
  mm/ioremap: track which page-table levels were modified
  mm/vmalloc: track which page-table levels were modified
  mm: add functions to track page directory modifications
  s390: use __vmalloc_node in stack_alloc
  powerpc: use __vmalloc_node in alloc_vm_stack
  arm64: use __vmalloc_node in arch_alloc_vmap_stack
  mm: remove vmalloc_user_node_flags
  mm: switch the test_vmalloc module to use __vmalloc_node
  mm: remove __vmalloc_node_flags_caller
  mm: remove both instances of __vmalloc_node_flags
  mm: remove the prot argument to __vmalloc_node
  mm: remove the pgprot argument to __vmalloc
  ...

Author: torvalds

Documentation/admin-guide/cgroup-v2.rst

@@ -1329,6 +1329,10 @@ PAGE_SIZE multiple when read back.
 	  workingset_activate
 		Number of refaulted pages that were immediately activated
 
+	  workingset_restore
+		Number of restored pages which have been detected as an active
+		workingset before they got reclaimed.
+
 	  workingset_nodereclaim
 		Number of times a shadow node has been reclaimed
 
@@ -1370,6 +1374,22 @@ PAGE_SIZE multiple when read back.
 	The total amount of swap currently being used by the cgroup
 	and its descendants.
 
+  memory.swap.high
+	A read-write single value file which exists on non-root
+	cgroups.  The default is "max".
+
+	Swap usage throttle limit.  If a cgroup's swap usage exceeds
+	this limit, all its further allocations will be throttled to
+	allow userspace to implement custom out-of-memory procedures.
+
+	This limit marks a point of no return for the cgroup. It is NOT
+	designed to manage the amount of swapping a workload does
+	during regular operation. Compare to memory.swap.max, which
+	prohibits swapping past a set amount, but lets the cgroup
+	continue unimpeded as long as other memory can be reclaimed.
+
+	Healthy workloads are not expected to reach this limit.
+
   memory.swap.max
 	A read-write single value file which exists on non-root
 	cgroups.  The default is "max".
@@ -1383,6 +1403,10 @@ PAGE_SIZE multiple when read back.
 	otherwise, a value change in this file generates a file
 	modified event.
 
+	  high
+		The number of times the cgroup's swap usage was over
+		the high threshold.
+
 	  max
 		The number of times the cgroup's swap usage was about
 		to go over the max boundary and swap allocation

Documentation/core-api/cachetlb.rst

@@ -213,7 +213,7 @@ Here are the routines, one by one:
 	there will be no entries in the cache for the kernel address
 	space for virtual addresses in the range 'start' to 'end-1'.
 
-	The first of these two routines is invoked after map_vm_area()
+	The first of these two routines is invoked after map_kernel_range()
 	has installed the page table entries.  The second is invoked
 	before unmap_kernel_range() deletes the page table entries.
 

Documentation/filesystems/locking.rst

@@ -239,6 +239,7 @@ prototypes::
 	int (*readpage)(struct file *, struct page *);
 	int (*writepages)(struct address_space *, struct writeback_control *);
 	int (*set_page_dirty)(struct page *page);
+	void (*readahead)(struct readahead_control *);
 	int (*readpages)(struct file *filp, struct address_space *mapping,
 			struct list_head *pages, unsigned nr_pages);
 	int (*write_begin)(struct file *, struct address_space *mapping,
@@ -271,7 +272,8 @@ writepage:		yes, unlocks (see below)
 readpage:		yes, unlocks
 writepages:
 set_page_dirty		no
-readpages:
+readahead:		yes, unlocks
+readpages:		no
 write_begin:		locks the page		 exclusive
 write_end:		yes, unlocks		 exclusive
 bmap:
@@ -295,6 +297,8 @@ the request handler (/dev/loop).
 ->readpage() unlocks the page, either synchronously or via I/O
 completion.
 
+->readahead() unlocks the pages that I/O is attempted on like ->readpage().
+
 ->readpages() populates the pagecache with the passed pages and starts
 I/O against them.  They come unlocked upon I/O completion.
 

Documentation/filesystems/proc.rst

@@ -1043,8 +1043,8 @@ PageTables
               amount of memory dedicated to the lowest level of page
               tables.
 NFS_Unstable
-              NFS pages sent to the server, but not yet committed to stable
-	      storage
+              Always zero. Previous counted pages which had been written to
+              the server, but has not been committed to stable storage.
 Bounce
               Memory used for block device "bounce buffers"
 WritebackTmp

Documentation/filesystems/vfs.rst

@@ -706,6 +706,7 @@ cache in your filesystem.  The following members are defined:
 		int (*readpage)(struct file *, struct page *);
 		int (*writepages)(struct address_space *, struct writeback_control *);
 		int (*set_page_dirty)(struct page *page);
+		void (*readahead)(struct readahead_control *);
 		int (*readpages)(struct file *filp, struct address_space *mapping,
 				 struct list_head *pages, unsigned nr_pages);
 		int (*write_begin)(struct file *, struct address_space *mapping,
@@ -781,12 +782,26 @@ cache in your filesystem.  The following members are defined:
 	If defined, it should set the PageDirty flag, and the
 	PAGECACHE_TAG_DIRTY tag in the radix tree.
 
+``readahead``
+	Called by the VM to read pages associated with the address_space
+	object.  The pages are consecutive in the page cache and are
+	locked.  The implementation should decrement the page refcount
+	after starting I/O on each page.  Usually the page will be
+	unlocked by the I/O completion handler.  If the filesystem decides
+	to stop attempting I/O before reaching the end of the readahead
+	window, it can simply return.  The caller will decrement the page
+	refcount and unlock the remaining pages for you.  Set PageUptodate
+	if the I/O completes successfully.  Setting PageError on any page
+	will be ignored; simply unlock the page if an I/O error occurs.
+
 ``readpages``
 	called by the VM to read pages associated with the address_space
 	object.  This is essentially just a vector version of readpage.
 	Instead of just one page, several pages are requested.
 	readpages is only used for read-ahead, so read errors are
 	ignored.  If anything goes wrong, feel free to give up.
+	This interface is deprecated and will be removed by the end of
+	2020; implement readahead instead.
 
 ``write_begin``
 	Called by the generic buffered write code to ask the filesystem

Documentation/vm/slub.rst

@@ -49,7 +49,7 @@ Possible debug options are::
 	P		Poisoning (object and padding)
 	U		User tracking (free and alloc)
 	T		Trace (please only use on single slabs)
-	A		Toggle failslab filter mark for the cache
+	A		Enable failslab filter mark for the cache
 	O		Switch debugging off for caches that would have
 			caused higher minimum slab orders
 	-		Switch all debugging off (useful if the kernel is

arch/arm/configs/omap2plus_defconfig

@@ -81,7 +81,7 @@ CONFIG_PARTITION_ADVANCED=y
 CONFIG_BINFMT_MISC=y
 CONFIG_CMA=y
 CONFIG_ZSMALLOC=m
-CONFIG_PGTABLE_MAPPING=y
+CONFIG_ZSMALLOC_PGTABLE_MAPPING=y
 CONFIG_NET=y
 CONFIG_PACKET=y
 CONFIG_UNIX=y

arch/arm64/include/asm/pgtable.h

@@ -407,6 +407,9 @@ static inline pmd_t pmd_mkdevmap(pmd_t pmd)
 #define __pgprot_modify(prot,mask,bits) \
 	__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
 
+#define pgprot_nx(prot) \
+	__pgprot_modify(prot, 0, PTE_PXN)
+
 /*
  * Mark the prot value as uncacheable and unbufferable.
  */

arch/arm64/include/asm/vmap_stack.h

@@ -19,10 +19,8 @@ static inline unsigned long *arch_alloc_vmap_stack(size_t stack_size, int node)
 {
 	BUILD_BUG_ON(!IS_ENABLED(CONFIG_VMAP_STACK));
 
-	return __vmalloc_node_range(stack_size, THREAD_ALIGN,
-				    VMALLOC_START, VMALLOC_END,
-				    THREADINFO_GFP, PAGE_KERNEL, 0, node,
-				    __builtin_return_address(0));
+	return __vmalloc_node(stack_size, THREAD_ALIGN, THREADINFO_GFP, node,
+			__builtin_return_address(0));
 }
 
 #endif /* __ASM_VMAP_STACK_H */

arch/arm64/mm/dump.c

@@ -252,7 +252,7 @@ static void note_prot_wx(struct pg_state *st, unsigned long addr)
 }
 
 static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
-		      unsigned long val)
+		      u64 val)
 {
 	struct pg_state *st = container_of(pt_st, struct pg_state, ptdump);
 	static const char units[] = "KMGTPE";