2022-04-26 08:08:41

by Stephen Zhang

Subject: [PATCH v2] bug: make __warn unconditionally defined

From: Shida Zhang <[email protected]>

__warn() was defined when CONFIG_BUG gets defined originally, but
it was used unconditonally by traps.c. So the idea is to have the
__warn unconditional.

Signed-off-by: Shida Zhang <[email protected]>
---
Changelog in v1 -> v2:
- To have the __warn() unconditional instead.

include/asm-generic/bug.h | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h
index edb0e2a602a8..ba1f860af38b 100644
--- a/include/asm-generic/bug.h
+++ b/include/asm-generic/bug.h
@@ -21,6 +21,12 @@
#include <linux/panic.h>
#include <linux/printk.h>

+struct warn_args;
+struct pt_regs;
+
+void __warn(const char *file, int line, void *caller, unsigned taint,
+ struct pt_regs *regs, struct warn_args *args);
+
#ifdef CONFIG_BUG

#ifdef CONFIG_GENERIC_BUG
@@ -110,11 +116,6 @@ extern __printf(1, 2) void __warn_printk(const char *fmt, ...);
#endif

/* used internally by panic.c */
-struct warn_args;
-struct pt_regs;
-
-void __warn(const char *file, int line, void *caller, unsigned taint,
- struct pt_regs *regs, struct warn_args *args);

#ifndef WARN_ON
#define WARN_ON(condition) ({ \
--
2.30.2

2022-04-27 07:09:14

by tip-bot2 for Jacob Pan

Subject: [tip: x86/urgent] bug: Have __warn() prototype defined unconditionally

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

Commit-ID: 1fa568e26f001e951b634d62ef3accdc80a87c7b
Gitweb: https://git.kernel.org/tip/1fa568e26f001e951b634d62ef3accdc80a87c7b
Author: Shida Zhang <[email protected]>
AuthorDate: Tue, 26 Apr 2022 11:20:07 +08:00
Committer: Borislav Petkov <[email protected]>
CommitterDate: Tue, 26 Apr 2022 10:59:57 +02:00

bug: Have __warn() prototype defined unconditionally

The __warn() prototype is declared in CONFIG_BUG scope but the function
definition in panic.c is unconditional. The IBT enablement started using
it unconditionally but a CONFIG_X86_KERNEL_IBT=y, CONFIG_BUG=n .config
will trigger a

arch/x86/kernel/traps.c: In function ‘__exc_control_protection’:
arch/x86/kernel/traps.c:249:17: error: implicit declaration of function \
‘__warn’; did you mean ‘pr_warn’? [-Werror=implicit-function-declaration]

Pull up the declarations so that they're unconditionally visible too.

[ bp: Rewrite commit message. ]

Fixes: 991625f3dd2c ("x86/ibt: Add IBT feature, MSR and #CP handling")
Suggested-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Shida Zhang <[email protected]>
Signed-off-by: Borislav Petkov <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
---
include/asm-generic/bug.h | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h
index edb0e2a..ba1f860 100644
--- a/include/asm-generic/bug.h
+++ b/include/asm-generic/bug.h
@@ -21,6 +21,12 @@
#include <linux/panic.h>
#include <linux/printk.h>

+struct warn_args;
+struct pt_regs;
+
+void __warn(const char *file, int line, void *caller, unsigned taint,
+ struct pt_regs *regs, struct warn_args *args);
+
#ifdef CONFIG_BUG

#ifdef CONFIG_GENERIC_BUG
@@ -110,11 +116,6 @@ extern __printf(1, 2) void __warn_printk(const char *fmt, ...);
#endif

/* used internally by panic.c */
-struct warn_args;
-struct pt_regs;
-
-void __warn(const char *file, int line, void *caller, unsigned taint,
- struct pt_regs *regs, struct warn_args *args);

#ifndef WARN_ON
#define WARN_ON(condition) ({ \