[PATCH v16 03/18] arm64: ptrace: Pass thread flags to syscall_trace_enter/exit()
From: Jinjie Ruan <hidden>
Date: 2026-06-29 13:06:53
Also in:
linux-alpha, linux-m68k, linux-mips, linux-mm, linux-riscv, linux-s390, linux-sh, linux-um, lkml, loongarch
Subsystem:
arm64 port (aarch64 architecture), ptrace support, the rest · Maintainers:
Catalin Marinas, Will Deacon, Oleg Nesterov, Linus Torvalds
Refactor syscall_trace_enter() and syscall_trace_exit() to move thread
flag reading to the caller. This aligns arm64's syscall trace enter/exit
function signature with generic entry framework.
[Changes]
1. Function signature changes:
- syscall_trace_enter(regs) → syscall_trace_enter(regs, flags)
- syscall_trace_exit(regs) → syscall_trace_exit(regs, flags)
2. Move flags reading to caller:
- Previously: read_thread_flags() called inside each function.
- Now: caller (like el0_svc_common) passes flags as parameter.
3. Update syscall.c:
- el0_svc_common() now passes flags to tracing functions and
re-fetches flags before entry/exit to handle potential TIF
updates.
[Why this matters]
- Aligns arm64 with the generic entry interface.
- Makes future migration to generic entry framework smoother.
No functional changes intended.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Ada Couprie Diaz <redacted>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Reviewed-by: Yeoreum Yun <redacted>
Reviewed-by: Kevin Brodsky <redacted>
Signed-off-by: Jinjie Ruan <redacted>
---
arch/arm64/include/asm/syscall.h | 4 ++--
arch/arm64/kernel/ptrace.c | 7 ++-----
arch/arm64/kernel/syscall.c | 5 +++--
3 files changed, 7 insertions(+), 9 deletions(-)
diff --git a/arch/arm64/include/asm/syscall.h b/arch/arm64/include/asm/syscall.h
index 5e4c7fc44f73..30b203ef156b 100644
--- a/arch/arm64/include/asm/syscall.h
+++ b/arch/arm64/include/asm/syscall.h@@ -120,7 +120,7 @@ static inline int syscall_get_arch(struct task_struct *task) return AUDIT_ARCH_AARCH64; } -int syscall_trace_enter(struct pt_regs *regs); -void syscall_trace_exit(struct pt_regs *regs); +int syscall_trace_enter(struct pt_regs *regs, unsigned long flags); +void syscall_trace_exit(struct pt_regs *regs, unsigned long flags); #endif /* __ASM_SYSCALL_H */
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 2ca6fab39a37..ac15b81a71b5 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c@@ -2408,9 +2408,8 @@ static void report_syscall_exit(struct pt_regs *regs) } } -int syscall_trace_enter(struct pt_regs *regs) +int syscall_trace_enter(struct pt_regs *regs, unsigned long flags) { - unsigned long flags = read_thread_flags(); int ret; if (flags & (_TIF_SYSCALL_EMU | _TIF_SYSCALL_TRACE)) {
@@ -2432,10 +2431,8 @@ int syscall_trace_enter(struct pt_regs *regs) return regs->syscallno; } -void syscall_trace_exit(struct pt_regs *regs) +void syscall_trace_exit(struct pt_regs *regs, unsigned long flags) { - unsigned long flags = read_thread_flags(); - audit_syscall_exit(regs); if (flags & _TIF_SYSCALL_TRACEPOINT)
diff --git a/arch/arm64/kernel/syscall.c b/arch/arm64/kernel/syscall.c
index 358ddfbf1401..c8e116397cfd 100644
--- a/arch/arm64/kernel/syscall.c
+++ b/arch/arm64/kernel/syscall.c@@ -113,7 +113,7 @@ static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr, */ if (scno == NO_SYSCALL) syscall_set_return_value(current, regs, -ENOSYS, 0); - scno = syscall_trace_enter(regs); + scno = syscall_trace_enter(regs, read_thread_flags()); if (scno == NO_SYSCALL) goto trace_exit; }
@@ -132,7 +132,8 @@ static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr, } trace_exit: - syscall_trace_exit(regs); + flags = read_thread_flags(); + syscall_trace_exit(regs, flags); } void do_el0_svc(struct pt_regs *regs)
--
2.34.1