2024-05-16 10:23:01

by Borislav Petkov

Subject: [PATCH] x86/boot: Add a fallthrough annotation

From: Borislav Petkov <[email protected]>

Add implicit fallthrough checking to the decompressor code and fix this
warning:

arch/x86/boot/printf.c: In function ‘vsprintf’:
arch/x86/boot/printf.c:248:10: warning: this statement may \
fall through [-Wimplicit-fallthrough=]
248 | flags |= SMALL;
| ^
arch/x86/boot/printf.c:249:3: note: here
249 | case 'X':
| ^~~~

This is a patch from three years ago which I found in my trees, thus the
SUSE authorship still.

Signed-off-by: Borislav Petkov <[email protected]>
Signed-off-by: Borislav Petkov (AMD) <[email protected]>
---
arch/x86/boot/Makefile | 1 +
arch/x86/boot/printf.c | 1 +
2 files changed, 2 insertions(+)

diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index 3cece19b7473..343aef6d752f 100644
--- a/arch/x86/boot/Makefile
+++ b/arch/x86/boot/Makefile
@@ -69,6 +69,7 @@ KBUILD_CFLAGS := $(REALMODE_CFLAGS) -D_SETUP
KBUILD_AFLAGS := $(KBUILD_CFLAGS) -D__ASSEMBLY__
KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
KBUILD_CFLAGS += -fno-asynchronous-unwind-tables
+KBUILD_CFLAGS += $(CONFIG_CC_IMPLICIT_FALLTHROUGH)
GCOV_PROFILE := n
UBSAN_SANITIZE := n

diff --git a/arch/x86/boot/printf.c b/arch/x86/boot/printf.c
index 1237beeb9540..c0ec1dc355ab 100644
--- a/arch/x86/boot/printf.c
+++ b/arch/x86/boot/printf.c
@@ -246,6 +246,7 @@ int vsprintf(char *buf, const char *fmt, va_list args)

case 'x':
flags |= SMALL;
+ fallthrough;
case 'X':
base = 16;
break;
--
2.43.0

2024-05-16 10:58:20

by tip-bot2 for Alexey Makhalov

Subject: [tip: x86/urgent] x86/boot: Add a fallthrough annotation

The following commit has been merged into the x86/urgent branch of tip:

Commit-ID: dd0716c2b87792ebea30864e7ad1df461d4c1525
Gitweb: https://git.kernel.org/tip/dd0716c2b87792ebea30864e7ad1df461d4c1525
Author: Borislav Petkov <[email protected]>
AuthorDate: Thu, 16 May 2024 12:22:40 +02:00
Committer: Ingo Molnar <[email protected]>
CommitterDate: Thu, 16 May 2024 12:46:36 +02:00

x86/boot: Add a fallthrough annotation

Add implicit fallthrough checking to the decompressor code and fix this
warning:

arch/x86/boot/printf.c: In function ‘vsprintf’:
arch/x86/boot/printf.c:248:10: warning: this statement may fall through [-Wimplicit-fallthrough=]
248 | flags |= SMALL;
| ^
arch/x86/boot/printf.c:249:3: note: here
249 | case 'X':
| ^~~~

This is a patch from three years ago which I found in my trees, thus the
SUSE authorship still.

Signed-off-by: Borislav Petkov <[email protected]>
Signed-off-by: Borislav Petkov (AMD) <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
---
arch/x86/boot/Makefile | 1 +
arch/x86/boot/printf.c | 1 +
2 files changed, 2 insertions(+)

diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index 3cece19..343aef6 100644
--- a/arch/x86/boot/Makefile
+++ b/arch/x86/boot/Makefile
@@ -69,6 +69,7 @@ KBUILD_CFLAGS := $(REALMODE_CFLAGS) -D_SETUP
KBUILD_AFLAGS := $(KBUILD_CFLAGS) -D__ASSEMBLY__
KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
KBUILD_CFLAGS += -fno-asynchronous-unwind-tables
+KBUILD_CFLAGS += $(CONFIG_CC_IMPLICIT_FALLTHROUGH)
GCOV_PROFILE := n
UBSAN_SANITIZE := n

diff --git a/arch/x86/boot/printf.c b/arch/x86/boot/printf.c
index 1237bee..c0ec1dc 100644
--- a/arch/x86/boot/printf.c
+++ b/arch/x86/boot/printf.c
@@ -246,6 +246,7 @@ int vsprintf(char *buf, const char *fmt, va_list args)

case 'x':
flags |= SMALL;
+ fallthrough;
case 'X':
base = 16;
break;