From 505a0ef15f96c6c43ec719c9fc1833d98957bb39 Mon Sep 17 00:00:00 2001
From: Alexander Potapenko <glider@google.com>
Date: Mon, 6 Apr 2020 20:10:22 -0700
Subject: [PATCH] kasan: stackdepot: move filter_irq_stacks() to stackdepot.c

filter_irq_stacks() can be used by other tools (e.g.  KMSAN), so it needs
to be moved to a common location.  lib/stackdepot.c seems a good place, as
filter_irq_stacks() is usually applied to the output of
stack_trace_save().

This patch has been previously mailed as part of KMSAN RFC patch series.

[glider@google.co: nds32: linker script: add SOFTIRQENTRY_TEXT\
  Link: http://lkml.kernel.org/r/20200311121002.241430-1-glider@google.com
[glider@google.com: add IRQENTRY_TEXT and SOFTIRQENTRY_TEXT to linker script]
  Link: http://lkml.kernel.org/r/20200311121124.243352-1-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Link: http://lkml.kernel.org/r/20200220141916.55455-3-glider@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 arch/ia64/kernel/vmlinux.lds.S  |  2 ++
 arch/nds32/kernel/vmlinux.lds.S |  1 +
 include/linux/stackdepot.h      |  2 ++
 lib/stackdepot.c                | 24 ++++++++++++++++++++++++
 mm/kasan/common.c               | 23 -----------------------
 5 files changed, 29 insertions(+), 23 deletions(-)

diff --git a/arch/ia64/kernel/vmlinux.lds.S b/arch/ia64/kernel/vmlinux.lds.S
index 1ec6b703c5b4..6b5652ee76f9 100644
--- a/arch/ia64/kernel/vmlinux.lds.S
+++ b/arch/ia64/kernel/vmlinux.lds.S
@@ -54,6 +54,8 @@ SECTIONS {
 		CPUIDLE_TEXT
 		LOCK_TEXT
 		KPROBES_TEXT
+		IRQENTRY_TEXT
+		SOFTIRQENTRY_TEXT
 		*(.gnu.linkonce.t*)
 	}
 
diff --git a/arch/nds32/kernel/vmlinux.lds.S b/arch/nds32/kernel/vmlinux.lds.S
index f679d3397436..7a6c1cefe3fe 100644
--- a/arch/nds32/kernel/vmlinux.lds.S
+++ b/arch/nds32/kernel/vmlinux.lds.S
@@ -47,6 +47,7 @@ SECTIONS
 		LOCK_TEXT
 		KPROBES_TEXT
 		IRQENTRY_TEXT
+		SOFTIRQENTRY_TEXT
 		*(.fixup)
 	}
 
diff --git a/include/linux/stackdepot.h b/include/linux/stackdepot.h
index 3efa97d482cb..24d49c732341 100644
--- a/include/linux/stackdepot.h
+++ b/include/linux/stackdepot.h
@@ -19,4 +19,6 @@ depot_stack_handle_t stack_depot_save(unsigned long *entries,
 unsigned int stack_depot_fetch(depot_stack_handle_t handle,
 			       unsigned long **entries);
 
+unsigned int filter_irq_stacks(unsigned long *entries, unsigned int nr_entries);
+
 #endif
diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index 1ec36ee344e0..2caffc64e4c8 100644
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -20,6 +20,7 @@
  */
 
 #include <linux/gfp.h>
+#include <linux/interrupt.h>
 #include <linux/jhash.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
@@ -316,3 +317,26 @@ depot_stack_handle_t stack_depot_save(unsigned long *entries,
 	return retval;
 }
 EXPORT_SYMBOL_GPL(stack_depot_save);
+
+static inline int in_irqentry_text(unsigned long ptr)
+{
+	return (ptr >= (unsigned long)&__irqentry_text_start &&
+		ptr < (unsigned long)&__irqentry_text_end) ||
+		(ptr >= (unsigned long)&__softirqentry_text_start &&
+		 ptr < (unsigned long)&__softirqentry_text_end);
+}
+
+unsigned int filter_irq_stacks(unsigned long *entries,
+					     unsigned int nr_entries)
+{
+	unsigned int i;
+
+	for (i = 0; i < nr_entries; i++) {
+		if (in_irqentry_text(entries[i])) {
+			/* Include the irqentry function into the stack. */
+			return i + 1;
+		}
+	}
+	return nr_entries;
+}
+EXPORT_SYMBOL_GPL(filter_irq_stacks);
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index e61b4a492218..2906358e42f0 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -15,7 +15,6 @@
  */
 
 #include <linux/export.h>
-#include <linux/interrupt.h>
 #include <linux/init.h>
 #include <linux/kasan.h>
 #include <linux/kernel.h>
@@ -42,28 +41,6 @@
 #include "kasan.h"
 #include "../slab.h"
 
-static inline int in_irqentry_text(unsigned long ptr)
-{
-	return (ptr >= (unsigned long)&__irqentry_text_start &&
-		ptr < (unsigned long)&__irqentry_text_end) ||
-		(ptr >= (unsigned long)&__softirqentry_text_start &&
-		 ptr < (unsigned long)&__softirqentry_text_end);
-}
-
-static inline unsigned int filter_irq_stacks(unsigned long *entries,
-					     unsigned int nr_entries)
-{
-	unsigned int i;
-
-	for (i = 0; i < nr_entries; i++) {
-		if (in_irqentry_text(entries[i])) {
-			/* Include the irqentry function into the stack. */
-			return i + 1;
-		}
-	}
-	return nr_entries;
-}
-
 static inline depot_stack_handle_t save_stack(gfp_t flags)
 {
 	unsigned long entries[KASAN_STACK_DEPTH];