While the TIF_SYSCALL_EMU is set in ptrace_resume independent of any architecture, currently only powerpc and x86 unset the TIF_SYSCALL_EMU flag in ptrace_disable which gets called from ptrace_detach.
Let's move the clearing of TIF_SYSCALL_EMU flag to __ptrace_unlink which gets executed from ptrace_detach and also keep it along with or close to clearing of TIF_SYSCALL_TRACE. Cc: Oleg Nesterov <o...@redhat.com> Cc: Paul Mackerras <pau...@samba.org> Cc: Michael Ellerman <m...@ellerman.id.au> Cc: Thomas Gleixner <t...@linutronix.de> Cc: Ingo Molnar <mi...@redhat.com> Signed-off-by: Sudeep Holla <sudeep.ho...@arm.com> --- arch/powerpc/kernel/ptrace.c | 1 - arch/x86/kernel/ptrace.c | 3 --- kernel/ptrace.c | 3 +++ 3 files changed, 3 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index d9ac7d94656e..2e2183b800a8 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -2520,7 +2520,6 @@ void ptrace_disable(struct task_struct *child) { /* make sure the single step bit is not set. */ user_disable_single_step(child); - clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); } #ifdef CONFIG_PPC_ADV_DEBUG_REGS diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c index 4b8ee05dd6ad..45792dbd2443 100644 --- a/arch/x86/kernel/ptrace.c +++ b/arch/x86/kernel/ptrace.c @@ -746,9 +746,6 @@ static int ioperm_get(struct task_struct *target, void ptrace_disable(struct task_struct *child) { user_disable_single_step(child); -#ifdef TIF_SYSCALL_EMU - clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); -#endif } #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 6f357f4fc859..16c7fc1eabcf 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -117,6 +117,9 @@ void __ptrace_unlink(struct task_struct *child) BUG_ON(!child->ptrace); clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); +#ifdef TIF_SYSCALL_EMU + clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); +#endif child->parent = child->real_parent; list_del_init(&child->ptrace_entry); -- 2.17.1