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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2019/3/1 2:32, Sudeep Holla wrote: > Now that we have a new hook ptrace_syscall_enter that can be called from > syscall entry code and it handles PTRACE_SYSEMU in generic code, we > can do some cleanup using the same in syscall_trace_enter. > > Further the extra logic to find single stepping PTRACE_SYSEMU_SINGLESTEP > in syscall_slow_exit_work seems unnecessary. Let's remove the same. I think we should not change the logic here. Is so, it will double the report of syscall when PTRACE_SYSEMU_SINGLESTEP is enabled. > > Cc: Andy Lutomirski > Cc: Thomas Gleixner > Cc: Ingo Molnar > Cc: Borislav Petkov > Signed-off-by: Sudeep Holla > --- > arch/x86/entry/common.c | 22 ++++------------------ > 1 file changed, 4 insertions(+), 18 deletions(-) > > diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c > index 7bc105f47d21..36457c1f87d2 100644 > --- a/arch/x86/entry/common.c > +++ b/arch/x86/entry/common.c > @@ -70,22 +70,16 @@ static long syscall_trace_enter(struct pt_regs *regs) > > struct thread_info *ti = current_thread_info(); > unsigned long ret = 0; > -bool emulated = false; > u32 work; > > if (IS_ENABLED(CONFIG_DEBUG_ENTRY)) > BUG_ON(regs != task_pt_regs(current)); > > -work = READ_ONCE(ti->flags) & _TIF_WORK_SYSCALL_ENTRY; > - > -if (unlikely(work & _TIF_SYSCALL_EMU)) > -emulated = true; > - > -if ((emulated || (work & _TIF_SYSCALL_TRACE)) && > - tracehook_report_syscall_entry(regs)) > +if (unlikely(ptrace_syscall_enter(regs))) > return -1L; > > -if (emulated) > +work = READ_ONCE(ti->flags) & _TIF_WORK_SYSCALL_ENTRY; > +if ((work & _TIF_SYSCALL_TRACE) && tracehook_report_syscall_entry(regs)) > return -1L; > > #ifdef CONFIG_SECCOMP > @@ -227,15 +221,7 @@ static void syscall_slow_exit_work(struct pt_regs *regs, u32 cached_flags) > if (cached_flags & _TIF_SYSCALL_TRACEPOINT) > trace_sys_exit(regs, regs->ax); > > -/* > - * If TIF_SYSCALL_EMU is set, we only get here because of > - * TIF_SINGLESTEP (i.e. this is PTRACE_SYSEMU_SINGLESTEP). > - * We already reported this syscall instruction in > - * syscall_trace_enter(). > - */ > -step = unlikely( > -(cached_flags & (_TIF_SINGLESTEP | _TIF_SYSCALL_EMU)) > -== _TIF_SINGLESTEP); > +step = unlikely((cached_flags & _TIF_SINGLESTEP)); > if (step || cached_flags & _TIF_SYSCALL_TRACE) > tracehook_report_syscall_exit(regs, step); > } > IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. 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