[patch 119/166] kasan: stackdepot: move filter_irq_stacks() to stackdepot.c

Andrew Morton
2020-04-07T03:10:25Z

From: Alexander Potapenko <glider@google.com>
Subject: 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
Link: http://lkml.kernel.org/r/20200220141916.55455-3-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
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>
Signed-off-by: Andrew Morton <akpm@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(-)

--- a/arch/ia64/kernel/vmlinux.lds.S~kasan-stackdepot-move-filter_irq_stacks-to-stackdepotc
+++ a/arch/ia64/kernel/vmlinux.lds.S
@@ -54,6 +54,8 @@ SECTIONS {
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
+ IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
*(.gnu.linkonce.t*)
}

--- a/arch/nds32/kernel/vmlinux.lds.S~kasan-stackdepot-move-filter_irq_stacks-to-stackdepotc
+++ a/arch/nds32/kernel/vmlinux.lds.S
@@ -47,6 +47,7 @@ SECTIONS
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
*(.fixup)
}

--- a/include/linux/stackdepot.h~kasan-stackdepot-move-filter_irq_stacks-to-stackdepotc
+++ a/include/linux/stackdepot.h
@@ -19,4 +19,6 @@ depot_stack_handle_t stack_depot_save(un
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
--- a/lib/stackdepot.c~kasan-stackdepot-move-filter_irq_stacks-to-stackdepotc
+++ a/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 @@ fast_exit:
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);
--- a/mm/kasan/common.c~kasan-stackdepot-move-filter_irq_stacks-to-stackdepotc
+++ a/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];
_