diff options
| author | Yuli Wang <wangyuli@uniontech.com> | 2025-03-30 16:31:09 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-04-10 14:41:51 +0200 |
| commit | ce0ed5d6efb086f267e7705416ce9c933f19cdf9 (patch) | |
| tree | 093a484db3af8944cb8b2e04f41c43ec851cc25e | |
| parent | 3c17da7863d6d3e643dad7392bec89bd166e0833 (diff) | |
LoongArch: Rework the arch_kgdb_breakpoint() implementation
[ Upstream commit 29c92a41c6d2879c1f62220fe4758dce191bb38f ]
The arch_kgdb_breakpoint() function defines the kgdb_breakinst symbol
using inline assembly.
1. There's a potential issue where the compiler might inline
arch_kgdb_breakpoint(), which would then define the kgdb_breakinst
symbol multiple times, leading to a linker error.
To prevent this, declare arch_kgdb_breakpoint() as noinline.
Fix follow error with LLVM-19 *only* when LTO_CLANG_FULL:
LD vmlinux.o
ld.lld-19: error: ld-temp.o <inline asm>:3:1: symbol 'kgdb_breakinst' is already defined
kgdb_breakinst: break 2
^
2. Remove "nop" in the inline assembly because it's meaningless for
LoongArch here.
3. Add "STACK_FRAME_NON_STANDARD" for arch_kgdb_breakpoint() to avoid
the objtool warning.
Fixes: e14dd076964e ("LoongArch: Add basic KGDB & KDB support")
Tested-by: Binbin Zhou <zhoubinbin@loongson.cn>
Co-developed-by: Winston Wen <wentao@uniontech.com>
Signed-off-by: Winston Wen <wentao@uniontech.com>
Co-developed-by: Wentao Guan <guanwentao@uniontech.com>
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
Signed-off-by: Yuli Wang <wangyuli@uniontech.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | arch/loongarch/kernel/kgdb.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/loongarch/kernel/kgdb.c b/arch/loongarch/kernel/kgdb.c index 445c452d72a7..7be5b4c0c900 100644 --- a/arch/loongarch/kernel/kgdb.c +++ b/arch/loongarch/kernel/kgdb.c @@ -8,6 +8,7 @@ #include <linux/hw_breakpoint.h> #include <linux/kdebug.h> #include <linux/kgdb.h> +#include <linux/objtool.h> #include <linux/processor.h> #include <linux/ptrace.h> #include <linux/sched.h> @@ -224,13 +225,13 @@ void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc) regs->csr_era = pc; } -void arch_kgdb_breakpoint(void) +noinline void arch_kgdb_breakpoint(void) { __asm__ __volatile__ ( \ ".globl kgdb_breakinst\n\t" \ - "nop\n" \ "kgdb_breakinst:\tbreak 2\n\t"); /* BRK_KDB = 2 */ } +STACK_FRAME_NON_STANDARD(arch_kgdb_breakpoint); /* * Calls linux_debug_hook before the kernel dies. If KGDB is enabled, |