From 397586506c3da005b9333ce5947ad01e8018a3be Mon Sep 17 00:00:00 2001
From: Nathan Chancellor <nathan@kernel.org>
Date: Tue, 23 Jan 2024 15:59:55 -0700
Subject: modpost: Add '.ltext' and '.ltext.*' to TEXT_SECTIONS

After the linked LLVM change, building ARCH=um defconfig results in a
segmentation fault in modpost. Prior to commit a23e7584ecf3 ("modpost:
unify 'sym' and 'to' in default_mismatch_handler()"), there was a
warning:

  WARNING: modpost: vmlinux.o(__ex_table+0x88): Section mismatch in reference to the .ltext:(unknown)
  WARNING: modpost: The relocation at __ex_table+0x88 references
  section ".ltext" which is not in the list of
  authorized sections.  If you're adding a new section
  and/or if this reference is valid, add ".ltext" to the
  list of authorized sections to jump to on fault.
  This can be achieved by adding ".ltext" to
  OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.

The linked LLVM change moves global objects to the '.ltext' (and
'.ltext.*' with '-ffunction-sections') sections with '-mcmodel=large',
which ARCH=um uses. These sections should be handled just as '.text'
and '.text.*' are, so add them to TEXT_SECTIONS.

Cc: stable@vger.kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/1981
Link: https://github.com/llvm/llvm-project/commit/4bf8a688956a759b7b6b8d94f42d25c13c7af130
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---
 scripts/mod/modpost.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(limited to 'scripts/mod/modpost.c')

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 795b21154446..acf72112acd8 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -806,7 +806,8 @@ static void check_section(const char *modname, struct elf_info *elf,
 
 #define DATA_SECTIONS ".data", ".data.rel"
 #define TEXT_SECTIONS ".text", ".text.*", ".sched.text", \
-		".kprobes.text", ".cpuidle.text", ".noinstr.text"
+		".kprobes.text", ".cpuidle.text", ".noinstr.text", \
+		".ltext", ".ltext.*"
 #define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \
 		".fixup", ".entry.text", ".exception.text", \
 		".coldtext", ".softirqentry.text"
-- 
cgit v1.2.3-70-g09d2


From cda5f94e88b45c9209599bac15fc44add5a59f60 Mon Sep 17 00:00:00 2001
From: Masahiro Yamada <masahiroy@kernel.org>
Date: Sat, 27 Jan 2024 22:28:11 +0900
Subject: modpost: avoid using the alias attribute

Aiden Leong reported modpost fails to build on macOS since commit
16a473f60edc ("modpost: inform compilers that fatal() never returns"):

  scripts/mod/modpost.c:93:21: error: aliases are not supported on darwin

Nathan's research indicates that Darwin seems to support weak aliases
at least [1]. Although the situation might be improved in future Clang
versions, we can achieve a similar outcome without relying on it.

This commit makes fatal() a macro of error() + exit(1) in modpost.h, as
compilers recognize that exit() never returns.

[1]: https://github.com/llvm/llvm-project/issues/71001

Fixes: 16a473f60edc ("modpost: inform compilers that fatal() never returns")
Reported-by: Aiden Leong <aiden.leong@aibsd.com>
Closes: https://lore.kernel.org/all/d9ac2960-6644-4a87-b5e4-4bfb6e0364a8@aibsd.com/
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---
 scripts/mod/modpost.c | 12 +-----------
 scripts/mod/modpost.h |  6 +-----
 2 files changed, 2 insertions(+), 16 deletions(-)

(limited to 'scripts/mod/modpost.c')

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index acf72112acd8..267b9a0a3abc 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -70,9 +70,7 @@ void modpost_log(enum loglevel loglevel, const char *fmt, ...)
 		break;
 	case LOG_ERROR:
 		fprintf(stderr, "ERROR: ");
-		break;
-	case LOG_FATAL:
-		fprintf(stderr, "FATAL: ");
+		error_occurred = true;
 		break;
 	default: /* invalid loglevel, ignore */
 		break;
@@ -83,16 +81,8 @@ void modpost_log(enum loglevel loglevel, const char *fmt, ...)
 	va_start(arglist, fmt);
 	vfprintf(stderr, fmt, arglist);
 	va_end(arglist);
-
-	if (loglevel == LOG_FATAL)
-		exit(1);
-	if (loglevel == LOG_ERROR)
-		error_occurred = true;
 }
 
-void __attribute__((alias("modpost_log")))
-modpost_log_noret(enum loglevel loglevel, const char *fmt, ...);
-
 static inline bool strends(const char *str, const char *postfix)
 {
 	if (strlen(str) < strlen(postfix))
diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
index 835cababf1b0..ee43c7950636 100644
--- a/scripts/mod/modpost.h
+++ b/scripts/mod/modpost.h
@@ -194,15 +194,11 @@ void *sym_get_data(const struct elf_info *info, const Elf_Sym *sym);
 enum loglevel {
 	LOG_WARN,
 	LOG_ERROR,
-	LOG_FATAL
 };
 
 void __attribute__((format(printf, 2, 3)))
 modpost_log(enum loglevel loglevel, const char *fmt, ...);
 
-void __attribute__((format(printf, 2, 3), noreturn))
-modpost_log_noret(enum loglevel loglevel, const char *fmt, ...);
-
 /*
  * warn - show the given message, then let modpost continue running, still
  *        allowing modpost to exit successfully. This should be used when
@@ -218,4 +214,4 @@ modpost_log_noret(enum loglevel loglevel, const char *fmt, ...);
  */
 #define warn(fmt, args...)	modpost_log(LOG_WARN, fmt, ##args)
 #define error(fmt, args...)	modpost_log(LOG_ERROR, fmt, ##args)
-#define fatal(fmt, args...)	modpost_log_noret(LOG_FATAL, fmt, ##args)
+#define fatal(fmt, args...)	do { error(fmt, ##args); exit(1); } while (1)
-- 
cgit v1.2.3-70-g09d2