1. Patchew
  2. linux
  3. View series

[PATCH V2] kasan: Cleanup the __HAVE_ARCH_SHADOW_MAP usage

Huacai Chen posted 1 patch 2 years, 3 months ago 
arch/loongarch/include/asm/kasan.h | 10 ++++++++--
include/linux/kasan.h              |  2 +-
mm/kasan/kasan.h                   |  8 +++-----
3 files changed, 12 insertions(+), 8 deletions(-)
[PATCH V2] kasan: Cleanup the __HAVE_ARCH_SHADOW_MAP usage
Posted by Huacai Chen 2 years, 3 months ago 
As Linus suggested, __HAVE_ARCH_XYZ is "stupid" and "having historical
uses of it doesn't make it good". So migrate __HAVE_ARCH_SHADOW_MAP to
separate macros named after the respective functions.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
---
V2: Update commit messages.

 arch/loongarch/include/asm/kasan.h | 10 ++++++++--
 include/linux/kasan.h              |  2 +-
 mm/kasan/kasan.h                   |  8 +++-----
 3 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/arch/loongarch/include/asm/kasan.h b/arch/loongarch/include/asm/kasan.h
index deeff8158f45..a12ecab37da7 100644
--- a/arch/loongarch/include/asm/kasan.h
+++ b/arch/loongarch/include/asm/kasan.h
@@ -10,8 +10,6 @@
 #include <asm/io.h>
 #include <asm/pgtable.h>
 
-#define __HAVE_ARCH_SHADOW_MAP
-
 #define KASAN_SHADOW_SCALE_SHIFT 3
 #define KASAN_SHADOW_OFFSET	_AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
 
@@ -68,6 +66,7 @@ static __always_inline bool kasan_arch_is_ready(void)
 	return !kasan_early_stage;
 }
 
+#define kasan_mem_to_shadow kasan_mem_to_shadow
 static inline void *kasan_mem_to_shadow(const void *addr)
 {
 	if (!kasan_arch_is_ready()) {
@@ -97,6 +96,7 @@ static inline void *kasan_mem_to_shadow(const void *addr)
 	}
 }
 
+#define kasan_shadow_to_mem kasan_shadow_to_mem
 static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
 {
 	unsigned long addr = (unsigned long)shadow_addr;
@@ -119,6 +119,12 @@ static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
 	}
 }
 
+#define addr_has_metadata addr_has_metadata
+static __always_inline bool addr_has_metadata(const void *addr)
+{
+	return (kasan_mem_to_shadow((void *)addr) != NULL);
+}
+
 void kasan_init(void);
 asmlinkage void kasan_early_init(void);
 
diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index 3df5499f7936..842623d708c2 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -54,7 +54,7 @@ extern p4d_t kasan_early_shadow_p4d[MAX_PTRS_PER_P4D];
 int kasan_populate_early_shadow(const void *shadow_start,
 				const void *shadow_end);
 
-#ifndef __HAVE_ARCH_SHADOW_MAP
+#ifndef kasan_mem_to_shadow
 static inline void *kasan_mem_to_shadow(const void *addr)
 {
 	return (void *)((unsigned long)addr >> KASAN_SHADOW_SCALE_SHIFT)
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index f70e3d7a602e..d37831b8511c 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -291,7 +291,7 @@ struct kasan_stack_ring {
 
 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 
-#ifndef __HAVE_ARCH_SHADOW_MAP
+#ifndef kasan_shadow_to_mem
 static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
 {
 	return (void *)(((unsigned long)shadow_addr - KASAN_SHADOW_OFFSET)
@@ -299,15 +299,13 @@ static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
 }
 #endif
 
+#ifndef addr_has_metadata
 static __always_inline bool addr_has_metadata(const void *addr)
 {
-#ifdef __HAVE_ARCH_SHADOW_MAP
-	return (kasan_mem_to_shadow((void *)addr) != NULL);
-#else
 	return (kasan_reset_tag(addr) >=
 		kasan_shadow_to_mem((void *)KASAN_SHADOW_START));
-#endif
 }
+#endif
 
 /**
  * kasan_check_range - Check memory region, and report if invalid access.
-- 
2.39.3
Re: [PATCH V2] kasan: Cleanup the __HAVE_ARCH_SHADOW_MAP usage
Posted by Andrey Konovalov 2 years, 3 months ago 
On Tue, Sep 12, 2023 at 5:18 AM Huacai Chen <chenhuacai@loongson.cn> wrote:
>
> As Linus suggested, __HAVE_ARCH_XYZ is "stupid" and "having historical
> uses of it doesn't make it good". So migrate __HAVE_ARCH_SHADOW_MAP to
> separate macros named after the respective functions.
>
> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
> Reviewed-by: WANG Xuerui <git@xen0n.name>
> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
> ---
> V2: Update commit messages.
>
>  arch/loongarch/include/asm/kasan.h | 10 ++++++++--
>  include/linux/kasan.h              |  2 +-
>  mm/kasan/kasan.h                   |  8 +++-----
>  3 files changed, 12 insertions(+), 8 deletions(-)
>
> diff --git a/arch/loongarch/include/asm/kasan.h b/arch/loongarch/include/asm/kasan.h
> index deeff8158f45..a12ecab37da7 100644
> --- a/arch/loongarch/include/asm/kasan.h
> +++ b/arch/loongarch/include/asm/kasan.h
> @@ -10,8 +10,6 @@
>  #include <asm/io.h>
>  #include <asm/pgtable.h>
>
> -#define __HAVE_ARCH_SHADOW_MAP
> -
>  #define KASAN_SHADOW_SCALE_SHIFT 3
>  #define KASAN_SHADOW_OFFSET    _AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
>
> @@ -68,6 +66,7 @@ static __always_inline bool kasan_arch_is_ready(void)
>         return !kasan_early_stage;
>  }
>
> +#define kasan_mem_to_shadow kasan_mem_to_shadow
>  static inline void *kasan_mem_to_shadow(const void *addr)
>  {
>         if (!kasan_arch_is_ready()) {
> @@ -97,6 +96,7 @@ static inline void *kasan_mem_to_shadow(const void *addr)
>         }
>  }
>
> +#define kasan_shadow_to_mem kasan_shadow_to_mem
>  static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
>  {
>         unsigned long addr = (unsigned long)shadow_addr;
> @@ -119,6 +119,12 @@ static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
>         }
>  }
>
> +#define addr_has_metadata addr_has_metadata
> +static __always_inline bool addr_has_metadata(const void *addr)
> +{
> +       return (kasan_mem_to_shadow((void *)addr) != NULL);
> +}
> +
>  void kasan_init(void);
>  asmlinkage void kasan_early_init(void);
>
> diff --git a/include/linux/kasan.h b/include/linux/kasan.h
> index 3df5499f7936..842623d708c2 100644
> --- a/include/linux/kasan.h
> +++ b/include/linux/kasan.h
> @@ -54,7 +54,7 @@ extern p4d_t kasan_early_shadow_p4d[MAX_PTRS_PER_P4D];
>  int kasan_populate_early_shadow(const void *shadow_start,
>                                 const void *shadow_end);
>
> -#ifndef __HAVE_ARCH_SHADOW_MAP
> +#ifndef kasan_mem_to_shadow
>  static inline void *kasan_mem_to_shadow(const void *addr)
>  {
>         return (void *)((unsigned long)addr >> KASAN_SHADOW_SCALE_SHIFT)
> diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
> index f70e3d7a602e..d37831b8511c 100644
> --- a/mm/kasan/kasan.h
> +++ b/mm/kasan/kasan.h
> @@ -291,7 +291,7 @@ struct kasan_stack_ring {
>
>  #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
>
> -#ifndef __HAVE_ARCH_SHADOW_MAP
> +#ifndef kasan_shadow_to_mem
>  static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
>  {
>         return (void *)(((unsigned long)shadow_addr - KASAN_SHADOW_OFFSET)
> @@ -299,15 +299,13 @@ static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
>  }
>  #endif
>
> +#ifndef addr_has_metadata
>  static __always_inline bool addr_has_metadata(const void *addr)
>  {
> -#ifdef __HAVE_ARCH_SHADOW_MAP
> -       return (kasan_mem_to_shadow((void *)addr) != NULL);
> -#else
>         return (kasan_reset_tag(addr) >=
>                 kasan_shadow_to_mem((void *)KASAN_SHADOW_START));
> -#endif
>  }
> +#endif
>
>  /**
>   * kasan_check_range - Check memory region, and report if invalid access.
> --
> 2.39.3
>

Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>

Thanks!
[PATCH V2] LoongArch: Don't inline kasan_mem_to_shadow()/kasan_shadow_to_mem()
Posted by Huacai Chen 2 years, 3 months ago 
As Linus suggested, kasan_mem_to_shadow()/kasan_shadow_to_mem() are not
performance-critical and too big to inline. This is simply wrong so just
define them out-of-line.

If they really need to be inlined in future, such as the objtool / SMAP
issue for X86, we should mark them __always_inline.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
---
 arch/loongarch/include/asm/kasan.h | 59 +++---------------------------
 arch/loongarch/mm/kasan_init.c     | 51 ++++++++++++++++++++++++++
 2 files changed, 57 insertions(+), 53 deletions(-)

diff --git a/arch/loongarch/include/asm/kasan.h b/arch/loongarch/include/asm/kasan.h
index a12ecab37da7..cd6084f4e153 100644
--- a/arch/loongarch/include/asm/kasan.h
+++ b/arch/loongarch/include/asm/kasan.h
@@ -60,63 +60,16 @@
 extern bool kasan_early_stage;
 extern unsigned char kasan_early_shadow_page[PAGE_SIZE];
 
-#define kasan_arch_is_ready kasan_arch_is_ready
-static __always_inline bool kasan_arch_is_ready(void)
-{
-	return !kasan_early_stage;
-}
-
 #define kasan_mem_to_shadow kasan_mem_to_shadow
-static inline void *kasan_mem_to_shadow(const void *addr)
-{
-	if (!kasan_arch_is_ready()) {
-		return (void *)(kasan_early_shadow_page);
-	} else {
-		unsigned long maddr = (unsigned long)addr;
-		unsigned long xrange = (maddr >> XRANGE_SHIFT) & 0xffff;
-		unsigned long offset = 0;
-
-		maddr &= XRANGE_SHADOW_MASK;
-		switch (xrange) {
-		case XKPRANGE_CC_SEG:
-			offset = XKPRANGE_CC_SHADOW_OFFSET;
-			break;
-		case XKPRANGE_UC_SEG:
-			offset = XKPRANGE_UC_SHADOW_OFFSET;
-			break;
-		case XKVRANGE_VC_SEG:
-			offset = XKVRANGE_VC_SHADOW_OFFSET;
-			break;
-		default:
-			WARN_ON(1);
-			return NULL;
-		}
-
-		return (void *)((maddr >> KASAN_SHADOW_SCALE_SHIFT) + offset);
-	}
-}
+void *kasan_mem_to_shadow(const void *addr);
 
 #define kasan_shadow_to_mem kasan_shadow_to_mem
-static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
+const void *kasan_shadow_to_mem(const void *shadow_addr);
+
+#define kasan_arch_is_ready kasan_arch_is_ready
+static __always_inline bool kasan_arch_is_ready(void)
 {
-	unsigned long addr = (unsigned long)shadow_addr;
-
-	if (unlikely(addr > KASAN_SHADOW_END) ||
-		unlikely(addr < KASAN_SHADOW_START)) {
-		WARN_ON(1);
-		return NULL;
-	}
-
-	if (addr >= XKVRANGE_VC_SHADOW_OFFSET)
-		return (void *)(((addr - XKVRANGE_VC_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT) + XKVRANGE_VC_START);
-	else if (addr >= XKPRANGE_UC_SHADOW_OFFSET)
-		return (void *)(((addr - XKPRANGE_UC_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT) + XKPRANGE_UC_START);
-	else if (addr >= XKPRANGE_CC_SHADOW_OFFSET)
-		return (void *)(((addr - XKPRANGE_CC_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT) + XKPRANGE_CC_START);
-	else {
-		WARN_ON(1);
-		return NULL;
-	}
+	return !kasan_early_stage;
 }
 
 #define addr_has_metadata addr_has_metadata
diff --git a/arch/loongarch/mm/kasan_init.c b/arch/loongarch/mm/kasan_init.c
index da68bc1a4643..cc3e81fe0186 100644
--- a/arch/loongarch/mm/kasan_init.c
+++ b/arch/loongarch/mm/kasan_init.c
@@ -35,6 +35,57 @@ static pgd_t kasan_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
 
 bool kasan_early_stage = true;
 
+void *kasan_mem_to_shadow(const void *addr)
+{
+	if (!kasan_arch_is_ready()) {
+		return (void *)(kasan_early_shadow_page);
+	} else {
+		unsigned long maddr = (unsigned long)addr;
+		unsigned long xrange = (maddr >> XRANGE_SHIFT) & 0xffff;
+		unsigned long offset = 0;
+
+		maddr &= XRANGE_SHADOW_MASK;
+		switch (xrange) {
+		case XKPRANGE_CC_SEG:
+			offset = XKPRANGE_CC_SHADOW_OFFSET;
+			break;
+		case XKPRANGE_UC_SEG:
+			offset = XKPRANGE_UC_SHADOW_OFFSET;
+			break;
+		case XKVRANGE_VC_SEG:
+			offset = XKVRANGE_VC_SHADOW_OFFSET;
+			break;
+		default:
+			WARN_ON(1);
+			return NULL;
+		}
+
+		return (void *)((maddr >> KASAN_SHADOW_SCALE_SHIFT) + offset);
+	}
+}
+
+const void *kasan_shadow_to_mem(const void *shadow_addr)
+{
+	unsigned long addr = (unsigned long)shadow_addr;
+
+	if (unlikely(addr > KASAN_SHADOW_END) ||
+		unlikely(addr < KASAN_SHADOW_START)) {
+		WARN_ON(1);
+		return NULL;
+	}
+
+	if (addr >= XKVRANGE_VC_SHADOW_OFFSET)
+		return (void *)(((addr - XKVRANGE_VC_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT) + XKVRANGE_VC_START);
+	else if (addr >= XKPRANGE_UC_SHADOW_OFFSET)
+		return (void *)(((addr - XKPRANGE_UC_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT) + XKPRANGE_UC_START);
+	else if (addr >= XKPRANGE_CC_SHADOW_OFFSET)
+		return (void *)(((addr - XKPRANGE_CC_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT) + XKPRANGE_CC_START);
+	else {
+		WARN_ON(1);
+		return NULL;
+	}
+}
+
 /*
  * Alloc memory for shadow memory page table.
  */
-- 
2.39.3

Patchew 2.1-devel-b67e4c2

© 2016 - 2025 Red Hat, Inc.