Re: [PATCH 16/18] arm64: ptrace: handle ptrace_request differently for aarch32 and ilp32

From	Catalin Marinas <catalin.marinas@arm.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH 16/18] arm64: ptrace: handle ptrace_request differently for aarch32 and ilp32
Date	2016-12-07 18:00 +0100
Message-ID	<sLNJx-2Ce-77@gated-at.bofh.it> (permalink)
References	<svVUK-5lu-13@gated-at.bofh.it> <sL4t4-6UN-43@gated-at.bofh.it> <sL4t4-6UN-41@gated-at.bofh.it> <sLNJx-2Ce-79@gated-at.bofh.it>
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On Tue, Dec 06, 2016 at 11:55:08AM +0530, Yury Norov wrote:
> On Mon, Dec 05, 2016 at 04:34:23PM +0000, Catalin Marinas wrote:
> > On Fri, Oct 21, 2016 at 11:33:15PM +0300, Yury Norov wrote:
> > > New aarch32 ptrace syscall handler is introduced to avoid run-time
> > > detection of the task type.
> > 
> > What's wrong with the run-time detection? If it's just to avoid a
> > negligible overhead, I would rather keep the code simpler by avoiding
> > duplicating the generic compat_sys_ptrace().
> 
> Nothing wrong. This is how Arnd asked me to do. You already asked this
> question: http://lkml.iu.edu/hypermail/linux/kernel/1604.3/00930.html

Hmm, I completely forgot about this ;). There is still an advantage to
doing run-time checking if we avoid touching core code (less acks to
gather and less code duplication).

Let's see what Arnd says but the initial patch looked simpler.

-- 
Catalin

Thread

Re: [PATCH 16/18] arm64: ptrace: handle ptrace_request differently  for aarch32 and ilp32 Catalin Marinas <catalin.marinas@arm.com> - 2016-12-05 17:40 +0100
  Re: [PATCH 16/18] arm64: ptrace: handle ptrace_request differently  for aarch32 and ilp32 Catalin Marinas <catalin.marinas@arm.com> - 2016-12-07 18:00 +0100
    Re: [PATCH 16/18] arm64: ptrace: handle ptrace_request differently for aarch32 and ilp32 Arnd Bergmann <arnd@arndb.de> - 2016-12-07 21:50 +0100
      Re: [PATCH 16/18] arm64: ptrace: handle ptrace_request differently  for aarch32 and ilp32 Catalin Marinas <catalin.marinas@arm.com> - 2016-12-08 14:20 +0100

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