| Message ID | 20190523090618.13410-3-sudeep.holla@arm.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | ptrace: cleanup PTRACE_SYSEMU handling and add support for arm64 | expand |
On Thu, May 23, 2019 at 10:06:16AM +0100, Sudeep Holla wrote: > The usage of emulated/_TIF_SYSCALL_EMU flags in syscall_trace_enter > seems to be bit overcomplicated than required. Let's simplify it. > > Cc: Andy Lutomirski <luto@kernel.org> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Ingo Molnar <mingo@redhat.com> > Cc: Borislav Petkov <bp@alien8.de> > Acked-by: Oleg Nesterov <oleg@redhat.com> > Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> > --- > arch/x86/entry/common.c | 17 ++++++----------- > 1 file changed, 6 insertions(+), 11 deletions(-) > > diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c > index a986b3c8294c..0a61705d62ec 100644 > --- a/arch/x86/entry/common.c > +++ b/arch/x86/entry/common.c > @@ -72,23 +72,18 @@ 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; > + work = READ_ONCE(ti->flags); > > - if (unlikely(work & _TIF_SYSCALL_EMU)) > - emulated = true; > - > - if ((emulated || (work & _TIF_SYSCALL_TRACE)) && > - tracehook_report_syscall_entry(regs)) > - return -1L; > - > - if (emulated) > - return -1L; > + if (work & (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU)) { > + ret = tracehook_report_syscall_entry(regs); > + if (ret || (work & _TIF_SYSCALL_EMU)) > + return -1L; > + } Andy (or the other x86 folk), could I please get an ack on this patch? I plan to queue this series through the arm64 tree (though if you want to merge it separately, it looks like an independent clean-up with no dependencies on the other patches). Thanks. -- Catalin
On Thu, 23 May 2019, Sudeep Holla wrote: $Subject: Please use the proper prefix and start the sentence with an upper case letter. x86/entry: Simplify _TIF_SYSCALL_EMU handling > The usage of emulated/_TIF_SYSCALL_EMU flags in syscall_trace_enter > seems to be bit overcomplicated than required. Let's simplify it. s/seems to be bit overcomplicated/is more complicated/ Either you are sure that it is overengineered, then say so. If not, then you should not touch the code at all. s/Let's simplify it.// 'Let's do X.' is a popular, but technically useless phrase. > Cc: Andy Lutomirski <luto@kernel.org> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Ingo Molnar <mingo@redhat.com> > Cc: Borislav Petkov <bp@alien8.de> > Acked-by: Oleg Nesterov <oleg@redhat.com> > Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> This is a nice simplification indeed! With the changelog fixed: Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index a986b3c8294c..0a61705d62ec 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -72,23 +72,18 @@ 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; + work = READ_ONCE(ti->flags); - if (unlikely(work & _TIF_SYSCALL_EMU)) - emulated = true; - - if ((emulated || (work & _TIF_SYSCALL_TRACE)) && - tracehook_report_syscall_entry(regs)) - return -1L; - - if (emulated) - return -1L; + if (work & (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU)) { + ret = tracehook_report_syscall_entry(regs); + if (ret || (work & _TIF_SYSCALL_EMU)) + return -1L; + } #ifdef CONFIG_SECCOMP /*