Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:
 "118 patches:

   - The rest of MM.

     Includes kfence - another runtime memory validator. Not as thorough
     as KASAN, but it has unmeasurable overhead and is intended to be
     usable in production builds.

   - Everything else

  Subsystems affected by this patch series: alpha, procfs, sysctl,
  misc, core-kernel, MAINTAINERS, lib, bitops, checkpatch, init,
  coredump, seq_file, gdb, ubsan, initramfs, and mm (thp, cma,
  vmstat, memory-hotplug, mlock, rmap, zswap, zsmalloc, cleanups,
  kfence, kasan2, and pagemap2)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
  MIPS: make userspace mapping young by default
  initramfs: panic with memory information
  ubsan: remove overflow checks
  kgdb: fix to kill breakpoints on initmem after boot
  scripts/gdb: fix list_for_each
  x86: fix seq_file iteration for pat/memtype.c
  seq_file: document how per-entry resources are managed.
  fs/coredump: use kmap_local_page()
  init/Kconfig: fix a typo in CC_VERSION_TEXT help text
  init: clean up early_param_on_off() macro
  init/version.c: remove Version_<LINUX_VERSION_CODE> symbol
  checkpatch: do not apply "initialise globals to 0" check to BPF progs
  checkpatch: don't warn about colon termination in linker scripts
  checkpatch: add kmalloc_array_node to unnecessary OOM message check
  checkpatch: add warning for avoiding .L prefix symbols in assembly files
  checkpatch: improve TYPECAST_INT_CONSTANT test message
  checkpatch: prefer ftrace over function entry/exit printks
  checkpatch: trivial style fixes
  checkpatch: ignore warning designated initializers using NR_CPUS
  checkpatch: improve blank line after declaration test
  ...

1 files changed, 31 insertions, 6 deletions

diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index 890dcc2e984e..49f67a0c6e5d 100644
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -31,6 +31,7 @@
 #include <linux/stackdepot.h>
 #include <linux/string.h>
 #include <linux/types.h>
+#include <linux/memblock.h>
 
 #define DEPOT_STACK_BITS (sizeof(depot_stack_handle_t) * 8)
 
@@ -141,14 +142,38 @@ static struct stack_record *depot_alloc_stack(unsigned long *entries, int size,
 	return stack;
 }
 
-#define STACK_HASH_ORDER 20
-#define STACK_HASH_SIZE (1L << STACK_HASH_ORDER)
+#define STACK_HASH_SIZE (1L << CONFIG_STACK_HASH_ORDER)
 #define STACK_HASH_MASK (STACK_HASH_SIZE - 1)
 #define STACK_HASH_SEED 0x9747b28c
 
-static struct stack_record *stack_table[STACK_HASH_SIZE] = {
-	[0 ...	STACK_HASH_SIZE - 1] = NULL
-};
+static bool stack_depot_disable;
+static struct stack_record **stack_table;
+
+static int __init is_stack_depot_disabled(char *str)
+{
+	int ret;
+
+	ret = kstrtobool(str, &stack_depot_disable);
+	if (!ret && stack_depot_disable) {
+		pr_info("Stack Depot is disabled\n");
+		stack_table = NULL;
+	}
+	return 0;
+}
+early_param("stack_depot_disable", is_stack_depot_disabled);
+
+int __init stack_depot_init(void)
+{
+	if (!stack_depot_disable) {
+		size_t size = (STACK_HASH_SIZE * sizeof(struct stack_record *));
+		int i;
+
+		stack_table = memblock_alloc(size, size);
+		for (i = 0; i < STACK_HASH_SIZE;  i++)
+			stack_table[i] = NULL;
+	}
+	return 0;
+}
 
 /* Calculate hash for a stack */
 static inline u32 hash_stack(unsigned long *entries, unsigned int size)
@@ -242,7 +267,7 @@ depot_stack_handle_t stack_depot_save(unsigned long *entries,
 	unsigned long flags;
 	u32 hash;
 
-	if (unlikely(nr_entries == 0))
+	if (unlikely(nr_entries == 0) || stack_depot_disable)
 		goto fast_exit;
 
 	hash = hash_stack(entries, nr_entries);