The patch titled
Subject: riscv: remove MCOUNT_NAME workaround
has been added to the -mm mm-nonmm-unstable branch. Its filename is
riscv-remove-mcount_name-workaround.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/riscv-remove-mcount_name-workaround.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Nathan Chancellor <nathan@xxxxxxxxxx>
Subject: riscv: remove MCOUNT_NAME workaround
Date: Thu, 25 Jan 2024 15:55:13 -0700
Now that the minimum supported version of LLVM for building the kernel has
been bumped to 13.0.1, the condition for using _mcount as MCOUNT_NAME is
always true, as the build will fail during the configuration stage for
older LLVM versions. Replace MCOUNT_NAME with _mcount directly.
This effectively reverts commit 7ce047715030 ("riscv: Workaround mcount
name prior to clang-13").
Link: https://lkml.kernel.org/r/20240125-bump-min-llvm-ver-to-13-0-1-v1-7-f5ff9bda41c5@xxxxxxxxxx
Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Albert Ou <aou@xxxxxxxxxxxxxxxxx>
Cc: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@xxxxxxxxxx>
Cc: Ard Biesheuvel <ardb@xxxxxxxxxx>
Cc: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Conor Dooley <conor@xxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: "Naveen N. Rao" <naveen.n.rao@xxxxxxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Nicolas Schier <nicolas@xxxxxxxxx>
Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx>
Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/riscv/include/asm/ftrace.h | 14 ++------------
arch/riscv/kernel/mcount.S | 10 +++++-----
scripts/recordmcount.pl | 2 +-
3 files changed, 8 insertions(+), 18 deletions(-)
--- a/arch/riscv/include/asm/ftrace.h~riscv-remove-mcount_name-workaround
+++ a/arch/riscv/include/asm/ftrace.h
@@ -13,19 +13,9 @@
#endif
#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
-/*
- * Clang prior to 13 had "mcount" instead of "_mcount":
- * https://github.com/llvm/llvm-project/commit/ef58ae86ba778ed7d01cd3f6bd6d08f943abab44
- */
-#if defined(CONFIG_CC_IS_GCC) || CONFIG_CLANG_VERSION >= 130000
-#define MCOUNT_NAME _mcount
-#else
-#define MCOUNT_NAME mcount
-#endif
-
#define ARCH_SUPPORTS_FTRACE_OPS 1
#ifndef __ASSEMBLY__
-void MCOUNT_NAME(void);
+void _mcount(void);
static inline unsigned long ftrace_call_adjust(unsigned long addr)
{
return addr;
@@ -75,7 +65,7 @@ struct dyn_arch_ftrace {
* both auipc and jalr at the same time.
*/
-#define MCOUNT_ADDR ((unsigned long)MCOUNT_NAME)
+#define MCOUNT_ADDR ((unsigned long)_mcount)
#define JALR_SIGN_MASK (0x00000800)
#define JALR_OFFSET_MASK (0x00000fff)
#define AUIPC_OFFSET_MASK (0xfffff000)
--- a/arch/riscv/kernel/mcount.S~riscv-remove-mcount_name-workaround
+++ a/arch/riscv/kernel/mcount.S
@@ -50,8 +50,8 @@
SYM_TYPED_FUNC_START(ftrace_stub)
#ifdef CONFIG_DYNAMIC_FTRACE
- .global MCOUNT_NAME
- .set MCOUNT_NAME, ftrace_stub
+ .global _mcount
+ .set _mcount, ftrace_stub
#endif
ret
SYM_FUNC_END(ftrace_stub)
@@ -80,7 +80,7 @@ SYM_FUNC_END(return_to_handler)
#endif
#ifndef CONFIG_DYNAMIC_FTRACE
-SYM_FUNC_START(MCOUNT_NAME)
+SYM_FUNC_START(_mcount)
la t4, ftrace_stub
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
la t0, ftrace_graph_return
@@ -126,6 +126,6 @@ SYM_FUNC_START(MCOUNT_NAME)
jalr t5
RESTORE_ABI_STATE
ret
-SYM_FUNC_END(MCOUNT_NAME)
+SYM_FUNC_END(_mcount)
#endif
-EXPORT_SYMBOL(MCOUNT_NAME)
+EXPORT_SYMBOL(_mcount)
--- a/scripts/recordmcount.pl~riscv-remove-mcount_name-workaround
+++ a/scripts/recordmcount.pl
@@ -352,7 +352,7 @@ if ($arch eq "x86_64") {
$mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\s_mcount\$";
} elsif ($arch eq "riscv") {
$function_regex = "^([0-9a-fA-F]+)\\s+<([^.0-9][0-9a-zA-Z_\\.]+)>:";
- $mcount_regex = "^\\s*([0-9a-fA-F]+):\\sR_RISCV_CALL(_PLT)?\\s_?mcount\$";
+ $mcount_regex = "^\\s*([0-9a-fA-F]+):\\sR_RISCV_CALL(_PLT)?\\s_mcount\$";
$type = ".quad";
$alignment = 2;
} elsif ($arch eq "csky") {
_
Patches currently in -mm which might be from nathan@xxxxxxxxxx are
selftests-bpf-update-llvm-phabricator-links.patch
arch-and-include-update-llvm-phabricator-links.patch
treewide-update-llvm-bugzilla-links.patch
kbuild-raise-the-minimum-supported-version-of-llvm-to-1301.patch
makefile-drop-warn-stack-size-plugin-opt.patch
x86-drop-stack-alignment-plugin-opt.patch
arm-remove-thumb2-__builtin_thread_pointer-workaround-for-clang.patch
arm64-kconfig-clean-up-tautological-llvm-version-checks.patch
powerpc-kconfig-remove-tautology-in-config_compat.patch
riscv-remove-mcount_name-workaround.patch
riscv-kconfig-remove-version-dependency-from-config_clang_supports_dynamic_ftrace.patch
fortify-drop-clang-version-check-for-1201-or-newer.patch
lib-kconfigdebug-update-clang-version-check-in-config_kcov.patch
compiler-clangh-update-__diag_clang-macros-for-minimum-version-bump.patch
