[PATCH v2 05/10] arm64: use a common struct frame_record
From: Mark Rutland <mark.rutland@arm.com>
Date: 2024-10-17 09:40:26
Subsystem:
arm64 port (aarch64 architecture), ptrace support, the rest · Maintainers:
Catalin Marinas, Will Deacon, Oleg Nesterov, Linus Torvalds
Currently the signal handling code has its own struct frame_record, the definition of struct pt_regs open-codes a frame record as an array, and the kernel unwinder hard-codes frame record offsets. Move to a common struct frame_record that can be used throughout the kernel. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Puranjay Mohan <redacted> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Kalesh Singh <redacted> Cc: Madhavan T. Venkataraman <redacted> Cc: Marc Zyngier <maz@kernel.org> Cc: Will Deacon <will@kernel.org> --- arch/arm64/include/asm/ptrace.h | 4 +++- arch/arm64/include/asm/stacktrace/common.h | 8 +++++--- arch/arm64/include/asm/stacktrace/frame.h | 13 +++++++++++++ arch/arm64/kernel/process.c | 2 +- arch/arm64/kernel/signal.c | 5 ----- arch/arm64/kernel/stacktrace.c | 2 +- 6 files changed, 23 insertions(+), 11 deletions(-) create mode 100644 arch/arm64/include/asm/stacktrace/frame.h
diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h
index 92531aeba5310..89c02f85f4b11 100644
--- a/arch/arm64/include/asm/ptrace.h
+++ b/arch/arm64/include/asm/ptrace.h@@ -98,6 +98,8 @@ #include <linux/bug.h> #include <linux/types.h> +#include <asm/stacktrace/frame.h> + /* sizeof(struct user) for AArch32 */ #define COMPAT_USER_SZ 296
@@ -168,7 +170,7 @@ struct pt_regs { u64 sdei_ttbr1; u64 unused; - u64 stackframe[2]; + struct frame_record stackframe; /* Only valid for some EL1 exceptions. */ u64 lockdep_hardirqs;
diff --git a/arch/arm64/include/asm/stacktrace/common.h b/arch/arm64/include/asm/stacktrace/common.h
index f63dc654e545f..7fab6876e4970 100644
--- a/arch/arm64/include/asm/stacktrace/common.h
+++ b/arch/arm64/include/asm/stacktrace/common.h@@ -137,21 +137,23 @@ static inline int unwind_consume_stack(struct unwind_state *state, static inline int unwind_next_frame_record(struct unwind_state *state) { + struct frame_record *record; unsigned long fp = state->fp; int err; if (fp & 0x7) return -EINVAL; - err = unwind_consume_stack(state, fp, 16); + err = unwind_consume_stack(state, fp, sizeof(*record)); if (err) return err; /* * Record this frame record's values. */ - state->fp = READ_ONCE(*(unsigned long *)(fp)); - state->pc = READ_ONCE(*(unsigned long *)(fp + 8)); + record = (struct frame_record *)fp; + state->fp = READ_ONCE(record->fp); + state->pc = READ_ONCE(record->lr); return 0; }
diff --git a/arch/arm64/include/asm/stacktrace/frame.h b/arch/arm64/include/asm/stacktrace/frame.h
new file mode 100644
index 0000000000000..6397bc847f147
--- /dev/null
+++ b/arch/arm64/include/asm/stacktrace/frame.h@@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +#ifndef __ASM_STACKTRACE_FRAME_H +#define __ASM_STACKTRACE_FRAME_H + +/* + * A standard AAPCS64 frame record. + */ +struct frame_record { + u64 fp; + u64 lr; +}; + +#endif /* __ASM_STACKTRACE_FRAME_H */
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index c722c1be6fa59..d45fd114eac3f 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c@@ -419,7 +419,7 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) * For the benefit of the unwinder, set up childregs->stackframe * as the final frame for the new task. */ - p->thread.cpu_context.fp = (unsigned long)childregs->stackframe; + p->thread.cpu_context.fp = (unsigned long)&childregs->stackframe; ptrace_hw_copy_thread(p);
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index 5619869475304..2c47f9a0e40ba 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c@@ -42,11 +42,6 @@ struct rt_sigframe { struct ucontext uc; }; -struct frame_record { - u64 fp; - u64 lr; -}; - struct rt_sigframe_user_layout { struct rt_sigframe __user *sigframe; struct frame_record __user *next_frame;
diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
index 2729faaee4b4c..ffe8e4f549566 100644
--- a/arch/arm64/kernel/stacktrace.c
+++ b/arch/arm64/kernel/stacktrace.c@@ -145,7 +145,7 @@ kunwind_next(struct kunwind_state *state) int err; /* Final frame; nothing to unwind */ - if (fp == (unsigned long)task_pt_regs(tsk)->stackframe) + if (fp == (unsigned long)&task_pt_regs(tsk)->stackframe) return -ENOENT; err = unwind_next_frame_record(&state->common);
--
2.30.2