[PATCH v8 17/43] kasan, arm64: move initialization message

Andrey Konovalov
2020-11-04T23:21:36Z

Software tag-based KASAN mode is fully initialized with kasan_init_tags(),
while the generic mode only requires kasan_init(). Move the
initialization message for tag-based mode into kasan_init_tags().

Also fix pr_fmt() usage for KASAN code: generic.c doesn't need it as it
doesn't use any printing functions; tag-based mode should use "kasan:"
instead of KBUILD_MODNAME (which stands for file name).

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
Change-Id: Iddca9764b30ff0fab1922f26ca9d4f39b6f22673
---
arch/arm64/include/asm/kasan.h | 9 +++------
arch/arm64/mm/kasan_init.c | 13 +++++--------
mm/kasan/generic.c | 2 --
mm/kasan/sw_tags.c | 4 +++-
4 files changed, 11 insertions(+), 17 deletions(-)

diff --git a/arch/arm64/include/asm/kasan.h b/arch/arm64/include/asm/kasan.h
index f7ea70d02cab..0aaf9044cd6a 100644
--- a/arch/arm64/include/asm/kasan.h
+++ b/arch/arm64/include/asm/kasan.h
@@ -12,14 +12,10 @@
#define arch_kasan_reset_tag(addr) __tag_reset(addr)
#define arch_kasan_get_tag(addr) __tag_get(addr)

-#ifdef CONFIG_KASAN
-void kasan_init(void);
-#else
-static inline void kasan_init(void) { }
-#endif
-
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)

+void kasan_init(void);
+
/*
* KASAN_SHADOW_START: beginning of the kernel virtual addresses.
* KASAN_SHADOW_END: KASAN_SHADOW_START + 1/N of kernel virtual addresses,
@@ -43,6 +39,7 @@ void kasan_copy_shadow(pgd_t *pgdir);
asmlinkage void kasan_early_init(void);

#else
+static inline void kasan_init(void) { }
static inline void kasan_copy_shadow(pgd_t *pgdir) { }
#endif

diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
index 5172799f831f..e35ce04beed1 100644
--- a/arch/arm64/mm/kasan_init.c
+++ b/arch/arm64/mm/kasan_init.c
@@ -278,17 +278,14 @@ static void __init kasan_init_depth(void)
init_task.kasan_depth = 0;
}

-#else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) */
-
-static inline void __init kasan_init_shadow(void) { }
-
-static inline void __init kasan_init_depth(void) { }
-
-#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
-
void __init kasan_init(void)
{
kasan_init_shadow();
kasan_init_depth();
+#if defined(CONFIG_KASAN_GENERIC)
+ /* CONFIG_KASAN_SW_TAGS also requires kasan_init_tags(). */
pr_info("KernelAddressSanitizer initialized\n");
+#endif
}
+
+#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
index e1af3b6c53b8..adb254df1b1d 100644
--- a/mm/kasan/generic.c
+++ b/mm/kasan/generic.c
@@ -9,8 +9,6 @@
* Andrey Konovalov <andreyknvl@gmail.com>
*/

-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
#include <linux/export.h>
#include <linux/interrupt.h>
#include <linux/init.h>
diff --git a/mm/kasan/sw_tags.c b/mm/kasan/sw_tags.c
index b2638c2cd58a..d25f8641b7cd 100644
--- a/mm/kasan/sw_tags.c
+++ b/mm/kasan/sw_tags.c
@@ -6,7 +6,7 @@
* Author: Andrey Konovalov <andreyknvl@google.com>
*/

-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#define pr_fmt(fmt) "kasan: " fmt

#include <linux/export.h>
#include <linux/interrupt.h>
@@ -41,6 +41,8 @@ void kasan_init_tags(void)

for_each_possible_cpu(cpu)
per_cpu(prng_state, cpu) = (u32)get_cycles();
+
+ pr_info("KernelAddressSanitizer initialized\n");
}

/*
--
2.29.1.341.ge80a0c044ae-goog